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Ng-NIST2012-AirQualityModeling-CONTAM.pdf
NIST Technical Note 1734
Airflow and Indoor Air Quality Models of
DOE Reference Commercial Buildings
Lisa C. Ng
Amy Musser
Andrew K. Persily
Steven J. Emmerich
6000
6000
4000
5000
# of Hours
# of Hours
5000
System On, CONTAM
System On, infilt., CONTAM
System Off, CONTAM
3000
4000
3000
2000
2000
1000
1000
0
0
Air Change Rate (h-1)
System On, E+
System On, infilt., E+
System Off, E+
Economizer, E+
Air Change Rate (h-1)
NIST Technical Note 1734
Airflow and Indoor Air Quality Models of
DOE Reference Commercial Buildings
Lisa C. Ng
Andrew K. Persily
Steven J. Emmerich
Energy and Environment Division
Engineering Laboratory
Amy Musser
Vandemusser Design PLLC
February 2012
U.S. Department of Commerce
John E. Bryson, Secretary
National Institute of Standards and Technology
Patrick D. Gallagher, Under Secretary of Commerce for Standards and Technology and Director
Certain commercial entities, equipment, or materials may be identified in this
document in order to describe an experimental procedure or concept adequately.
Such identification is not intended to imply recommendation or endorsement by the
National Institute of Standards and Technology, nor is it intended to imply that the
entities, materials, or equipment are necessarily the best available for the purpose.
National Institute of Standards and Technology Technical Note 1734
Natl. Inst. Stand. Technol. Tech. Note 1734, 163 Pages (February 2012)
CODEN: NTNOEF
ABSTRACT
Sixteen reference buildings have been defined by the U.S. Department of Energy, and created as
EnergyPlus input files, for use in assessing new technologies and supporting the development of
energy codes in pursuing building energy efficiency improvements. Infiltration rates in the
EnergyPlus models of the reference buildings were input as constant airflow rates, and not
calculated based on established building airflow theory. In order to support more
physically-based airflow calculations, as well as indoor air quality analysis, models of the
16 reference buildings were created in the multizone airflow and contaminant transport program
CONTAM. A number of additional inputs had to be defined for the CONTAM models, and
changes in the interior zoning were required, to more realistically account for airflow. Annual
airflow and contaminant simulations were performed in CONTAM for six of the buildings.
While the assumed infiltration rates in EnergyPlus do not realistically reflect impacts of weather
conditions, there are clear relationships between the outdoor air change rates calculated by
CONTAM and weather. In addition, the envelope airtightness values assumed in either approach
are seen to have a major impact on the air change rates. Contaminant analyses were performed
for occupant-generated carbon dioxide, volatile organic compounds from indoor sources, outdoor
particulate matter, and outdoor ozone. The airflow and contaminant calculation results provide a
useful baseline for subsequent use of these models to investigate approaches to building
ventilation and other technologies that are intended to simultaneously reduce building energy
consumption while maintaining or improving indoor air quality.
Keywords: airflow, energy, CONTAM, EnergyPlus, IAQ, reference buildings, ventilation
i
TABLE OF CONTENTS
LIST OF TABLES .......................................................................................................................... v
LIST OF FIGURES ...................................................................................................................... vii
1. INTRODUCTION ............................................................................................................... 1
2. BUILDING DESCRIPTIONS ............................................................................................. 3
3. MODELING APPROACH .................................................................................................. 3
3.1.
CONTAM model inputs ............................................................................................... 4
3.2.
EnergyPlus model inputs .............................................................................................. 8
4. AIRFLOW SIMULATION RESULTS ............................................................................. 10
4.1.
Outdoor air change rates ............................................................................................. 10
4.2.
Outdoor air change rates vs. weather conditions ........................................................ 19
4.3.
Impacts of infiltration on sensible load ...................................................................... 27
5. CONTAMINANT SIMULATION RESULTS.................................................................. 29
6. DISCUSSION .................................................................................................................... 52
6.1.
Building models for airflow and energy analyses ...................................................... 52
6.2.
Limitations of study .................................................................................................... 54
6.3.
Presenting IAQ simulation results .............................................................................. 54
6.4.
Future work................................................................................................................. 55
7. CONCLUSION .................................................................................................................. 56
8. REFERENCES .................................................................................................................. 57
Appendix A Detailed description of CONTAM models of reference buildings .......................... 61
A1.
INTRODUCTION .......................................................................................................... 61
A2.
BUILDINGS DESCRIPTION ....................................................................................... 63
A2.1.
Quick Service Restaurant ........................................................................................ 63
A2.2.
Full Service Restaurant ........................................................................................... 65
A2.3.
Small Office ............................................................................................................ 67
A2.4.
Medium Office ........................................................................................................ 70
A2.5.
Large Office ............................................................................................................ 74
A2.6.
Primary School........................................................................................................ 78
A2.7.
Secondary School.................................................................................................... 84
A2.8.
Stand-Alone Retail .................................................................................................. 92
A2.9.
Strip Mall ................................................................................................................ 95
iii
A2.10.
Supermarket ........................................................................................................ 97
A2.11.
Small Hotel........................................................................................................ 100
A2.12.
Large Hotel........................................................................................................ 106
A2.13.
Hospital ............................................................................................................. 113
A2.14.
Outpatient Health Care ...................................................................................... 123
A2.15.
Warehouse ......................................................................................................... 134
A2.16.
Midrise Apartment ............................................................................................ 137
Appendix B Detailed calculated contaminant concentration predictions ................................... 141
B1.
Full Service Restaurant ................................................................................................ 141
B2.
Hospital ........................................................................................................................ 142
B3.
Medium Office ............................................................................................................. 144
B4.
Primary School ............................................................................................................. 146
B5.
Small Hotel................................................................................................................... 147
B6.
Stand-Alone Retail ....................................................................................................... 149
iv
LIST OF TABLES
Table 1 Summary of reference buildings ........................................................................................ 4
Table 2 Properties of contaminants simulated in CONTAM.......................................................... 7
Table 3 Summary of outdoor contaminant concentrations for Chicago ......................................... 7
Table 4 Buildings for which economizer modeled for at least one HVAC system (Chicago) ....... 9
Table 5 Summary of calculated outdoor air change rates ............................................................. 12
Table 6 Sensible loads due to infiltration ..................................................................................... 27
Table 7 Selected zones for which contaminant concentration results reported ............................ 30
Table 8 Summary of calculated contaminant concentrations ....................................................... 31
Table A1 Summary of zones in Quick Service Restaurant........................................................... 63
Table A2 Summary of HVAC system flow rates (m3/s) in Quick Service Restaurant................. 64
Table A3 Summary of zones in Full Service Restaurant .............................................................. 65
Table A4 Summary of HVAC system flow rates (m3/s) in Full Service Restaurant .................... 66
Table A5 Summary of zones in Small Office ............................................................................... 68
Table A6 Summary of HVAC system flow rates (m3/s) in Small Office ..................................... 69
Table A7 Summary of zones in Medium Office ........................................................................... 70
Table A8 Summary of VAV system flow rates (m3/s) in Medium Office for
New and Post-1980 buildings ................................................................................................. 73
Table A9 Summary of CAV system flow rates in Medium Office for Pre-1980 building ........... 73
Table A10 Summary of zones in Large Office ............................................................................. 75
Table A11 Summary of VAV system flow rates (m3/s) in Large Office...................................... 77
Table A12 Summary of zones in Primary School ........................................................................ 79
Table A13 Summary of HVAC system flow rates (m3/s) in Primary School .............................. 82
Table A14 Summary of zones in Secondary School .................................................................... 85
Table A15 Summary of HVAC system flow rates (m3/s) in Secondary School .......................... 89
Table A16 Summary of zones in Stand-Alone Retail................................................................... 92
Table A17 Summary of HVAC system flow rates (m3/s) in Stand-Alone Retail......................... 94
Table A18 Summary of zones in Strip Mall ................................................................................. 95
Table A19 Summary of HVAC system flow rates (m3/s) in Strip Mall ....................................... 96
Table A20 Summary of zones in Supermarket ............................................................................. 97
Table A21 Summary of HVAC system flow rates (m3/s) in Supermarket ................................... 99
Table A22 Summary of zones in Small Hotel ............................................................................ 101
v
Table A23 Summary of HVAC system flow rates (m3/s) in Small Hotel .................................. 103
Table A24 Summary of PTAC flow rates (m3/s) in Small Hotel ............................................... 104
Table A25 Summary of zones in Large Hotel ............................................................................ 106
Table A26 Summary of VAV system flow rates (m3/s) in Large Hotel for
New and Post-1980 buildings ............................................................................................... 110
Table A27 Summary of CAV system flow rates (m3/s) in Large Hotel for Pre-1980 buildings 110
Table A28 Summary of DOAS flow rates (m3/s) in Large Hotel for all building vintages ....... 111
Table A29 Summary of zones in Hospital .................................................................................. 114
Table A30 Summary of VAV and CAV system flow rates (m3/s) in Hospital .......................... 121
Table A31 Summary of zones in Outpatient Health Care .......................................................... 123
Table A32 Summary of VAV system flow rates (m3/s) in Outpatient Healthcare ..................... 131
Table A33 Summary of zones in Warehouse ............................................................................. 134
Table A34 Summary of CAV system flow rates (m3/s) in Warehouse ...................................... 136
Table A35 Summary of zones and outside air rates in Midrise Apartment ................................ 137
vi
LIST OF FIGURES
Figure 1 Wind pressure profile simulated in CONTAM for exterior walls .................................... 5
Figure 2 Frequency distribution of simulated outdoor air change rates for
Full Service Restaurant ........................................................................................................... 16
Figure 3 Frequency distribution of simulated outdoor air change rates for Hospital ................... 16
Figure 4 Frequency distribution of simulated outdoor air change rates for Medium Office ........ 17
Figure 5 Frequency distribution of simulated outdoor air change rates for Primary School ........ 17
Figure 6 Frequency distribution of simulated outdoor air change rates for Small Hotel ............. 18
Figure 7 Frequency distribution of simulated outdoor air change rates for Stand-Alone Retail .. 18
Figure 8 Air change rates as a function of temperature difference (low wind speed) for
Full Service Restaurant ........................................................................................................... 21
Figure 9 Air change rates as a function of temperature difference (low wind speed) for
Hospital ................................................................................................................................... 21
Figure 10 Air change rates as a function of temperature difference (low wind speed) for
Medium Office ........................................................................................................................ 22
Figure 11 Air change rates as a function of temperature difference (low wind speed) for
Primary School........................................................................................................................ 22
Figure 12 Air change rates as a function of temperature difference (low wind speed) for
Small Hotel ............................................................................................................................. 23
Figure 13 Air change rates as a function of temperature difference (low wind speed) for
Stand-Alone Retail .................................................................................................................. 23
Figure 14 Air change rates as a function of wind speed (low ΔT) for Full Service Restaurant ... 24
Figure 15 Air change rates as a function of wind speed (low ΔT) for Hospital ........................... 24
Figure 16 Air change rates as a function of wind speed (low ΔT) for Medium Office ................ 25
Figure 17 Air change rates as a function of wind speed (low ΔT) for Primary School ................ 25
Figure 18 Air change rates as a function of wind speed (low ΔT) for Small Hotel ..................... 26
Figure 19 Air change rates as a function of wind speed (low ΔT) for Stand-Alone Retail .......... 26
Figure 20 Frequency distribution of simulated CO2 concentration for Full Service Restaurant .. 34
Figure 21 Frequency distribution of simulated CO2 concentration for Hospital .......................... 35
Figure 22 Frequency distribution of simulated CO2 concentration for Medium Office ............... 36
Figure 23 Frequency distribution of simulated CO2 concentration for Primary School............... 37
Figure 24 Frequency distribution of simulated CO2 concentration for Small Hotel .................... 38
Figure 25 Frequency distribution of simulated CO2 concentration for Stand-Alone Retail ......... 39
Figure 26 Frequency distribution of simulated VOC concentration for Full Service Restaurant 40
vii
Figure 27 Frequency distribution of simulated VOC concentration for Hospital ........................ 41
Figure 28 Frequency distribution of simulated VOC concentration for Medium Office ............. 42
Figure 29 Frequency distribution of simulated VOC concentration for Primary School ............. 43
Figure 30 Frequency distribution of simulated VOC concentration for Small Hotel ................... 44
Figure 31 Frequency distribution of simulated VOC concentration for Stand-Alone Retail ....... 45
Figure 32 Frequency distributions of simulated ozone and PM2.5 daily average
concentrations for Full Service Restaurant ............................................................................. 46
Figure 33 Frequency distributions of simulated ozone and PM2.5 daily average
concentrations for Hospital ..................................................................................................... 47
Figure 34 Frequency distributions of simulated ozone and PM2.5 daily average
concentrations for Medium Office .......................................................................................... 48
Figure 35 Frequency distributions of simulated ozone and PM2.5 daily average
concentrations for Primary School.......................................................................................... 49
Figure 36 Frequency distributions of simulated ozone and PM2.5 daily average
concentrations for Small Hotel ............................................................................................... 50
Figure 37 Frequency distributions of simulated ozone and PM2.5 daily average
concentrations for Stand-Alone Retail .................................................................................... 51
Figure A1 Floor plan of Quick Service Restaurant (height 3.05 m) ............................................. 63
Figure A2 Occupancy schedule for Quick Service Restaurant ..................................................... 65
Figure A3 Floor plan of Full Service Restaurant (height 3.05 m) ................................................ 66
Figure A4 Occupancy schedule for Full Service Restaurant ........................................................ 67
Figure A5 Floor plan of Small Office (height 3.05 m) ................................................................. 68
Figure A6 Occupancy schedule for Small Office ......................................................................... 69
Figure A7 Floor plan of Medium Office (height 2.74 m) ............................................................. 70
Figure A8 Occupancy schedule for Medium Office ..................................................................... 74
Figure A9 First floor plan of Large Office (height 2.74 m). Second through twelfth floors
are identical to first floor......................................................................................................... 75
Figure A10 Occupancy schedule for Large Office ....................................................................... 78
Figure A11 Plan of Primary School (height 4.0 m) ...................................................................... 80
Figure A12 Occupancy schedules for Primary School (Gym, Cafeteria) ..................................... 83
Figure A13 Occupancy schedules for Primary School (Offices, Class) ....................................... 83
Figure A14 First floor plan of Secondary School (height 4.0 m) ................................................. 86
Figure A15 Second floor plan of Secondary School (height 4.0 m) ............................................. 87
Figure A16 Occupancy schedules for Secondary School (Gym, Cafeteria, and Auditorium) ..... 91
viii
Figure A17 Occupancy schedules for Secondary School (Offices, Class) ................................... 92
Figure A18 Floor plan of Stand-Alone Retail (height 6.1 m) ....................................................... 93
Figure A19 Occupancy schedule for Stand-Alone Retail ............................................................. 94
Figure A20 Floor plan of Strip Mall (height 5.18 m) ................................................................... 95
Figure A21 Occupancy schedule for Strip Mall ........................................................................... 97
Figure A22 Floor plan of Supermarket (height 6.1 m) ................................................................. 98
Figure A23 Occupancy schedule for Supermarket ..................................................................... 100
Figure A24 (a) First and (b) upper floor (2-4) plans of Small Hotel .......................................... 102
Figure A25 Occupancy schedules for Small Hotel (Restroom and Exercise) ............................ 104
Figure A26 Occupancy schedules for Small Hotel (Lounges, Laundry, Meeting Room,
Office) ................................................................................................................................... 105
Figure A27 Occupancy schedule for Small Hotel (Guest) ......................................................... 105
Figure A28 (a) First, (b) second to fifth, and (c) sixth floors plans of Large Hotel ................... 108
Figure A29 Occupancy schedules for Large Hotel (Lobby, Guest) ........................................... 112
Figure A30 Occupancy schedule for Large Hotel (Building) ..................................................... 112
Figure A31 First floor plan of Hospital (height 4.27 m), all dimensions in meters.................... 116
Figure A32 Second floor plan of Hospital (height 4.27 m), all dimensions in meters ............... 117
Figure A33 Third/Fourth floor plans of Hospital (height 4.27 m), all dimensions in meters ..... 118
Figure A34 Fifth floor plans of Hospital (height 4.27 m), all dimensions in meters.................. 119
Figure A35 Occupancy schedules for Hospital .......................................................................... 122
Figure A36 First floor plan of Outpatient Health Care, all dimensions in meters ...................... 127
Figure A37 Second floor plan of Outpatient Health Care, all dimensions in meters ................. 128
Figure A38 Third floor plan of Outpatient Health Care, all dimensions in meters .................... 129
Figure A39 Occupancy schedule for Outpatient Health Care .................................................... 134
Figure A40 Floor plan of Warehouse (height 8.534 m, except for Office
which is 4.267 m high).......................................................................................................... 135
Figure A41 Occupancy schedule for Warehouse........................................................................ 136
Figure A42 Floor plan of Midrise Apartment (height 3.05 m) ................................................... 138
Figure A43 Occupancy schedules for Midrise Apartment ......................................................... 139
ix
1. INTRODUCTION
Heating, ventilating, and air conditioning (HVAC) systems in buildings are designed to provide
thermally comfortable conditions and to maintain acceptable indoor air quality (IAQ). At the
same time, the operating costs of HVAC systems are often a large percentage of the total energy
consumption of buildings, which constitutes 40 % of the primary energy consumed in the
U.S. (DOE 2010). In order to address the need to reduce the building sector’s contribution to the
nation’s energy consumption, a number of organizations and government agencies have set
energy-related goals and are pursuing research and other activities to support achieving those
goals. The American Society of Heating, Refrigerating, and Air-Conditioning Engineers
(ASHRAE) has set research goals for developing standards and design guides for achieving
cost-effective net-zero energy buildings (ASHRAE 2010c). The American Institute of Architects
has set carbon-neutral goals for all new and major-renovated buildings by 2030 (AIA 2006). The
U.S. Department of Energy (DOE) has set net-zero energy goals for both residential and
commercial buildings by 2025 (DOE 2008). The DOE Building Technologies Program (BTP)
supports research and development (R&D) activities to achieve these goals by improving the
efficiency of buildings. One of these R&D activities is the development of the building energy
simulation software EnergyPlus and its application to analyze building energy consumption and
energy efficiency opportunities. Under the BTP, 16 building models were created in EnergyPlus
to characterize more than 60 % of the commercial building stock in the U.S. (Deru et al. 2011).
These “reference” buildings include 15 commercial buildings and one multi-family residential
building. The commercial buildings include two restaurants, two health care centers, two hotels,
three office buildings, two schools, three retail buildings, and a warehouse. There are three
versions (or vintages) of each reference building: new, post-1980, and pre-1980 construction.
The three vintages differ in insulation values, infiltration rates, lighting levels, and type of
HVAC systems. The new construction models were developed to comply with the minimum
requirements of ANSI/ASHRAE/IESNA Standard 90.1-2004 (ASHRAE 2004), the post-1980
models to comply with the minimum requirements of Standard 90.1-1989 (ASHRAE 1989), and
the pre-1980 models to comply with requirements from previous standards and other studies of
construction practices.
The reference buildings were created to assess new technologies and support the development of
energy codes and standards, and therefore their definitions are focused on capturing energy
performance. However, some discussions of building energy efficiency neglect potential impacts
on indoor air quality (IAQ) or view acceptable IAQ as being in conflict with energy efficiency
(Persily and Emmerich 2012). However, saving energy at the expense of IAQ has the potential to
significantly impact the health, comfort, and productivity of building occupants. In addition,
there are many approaches to building design and operation that can improve both energy
efficiency and IAQ, such as heat recovery ventilation, demand control ventilation and
economizer operation (Persily and Emmerich 2012). One limitation in the implementation of
certain energy efficiency technologies and the consideration of their impacts on IAQ is that
current energy design and analysis tools are limited in their ability to model building airflow and
IAQ in a physically reasonable fashion.
A review of the airflow and IAQ analyses capabilities of five of the most widely used energy
simulation software tools, including EnergyPlus, found that many of the infiltration models
employed by energy simulation software are based on calculation methods developed for
1
low-rise, residential buildings (Ng and Persily 2011). These methods are not generally
appropriate for other types of buildings, specifically taller buildings with mechanical ventilation
systems, more airtight separations between floors, and vertical shafts. Also, these empirical
infiltration models require the user to specify air leakage coefficients that are best obtained from
building pressurization tests (ASTM 2010), for which only limited data are available for larger
buildings (Emmerich and Persily 2011). Many energy simulation software users assume constant
infiltration rates, which do not reflect known dependencies on indoor-outdoor conditions and
ventilation system operation. However, airflow calculations, using existing theory and methods,
are the only technically sound means of determining the airflow rates that are important for
analyzing energy use and IAQ.
EnergyPlus has a so-called “Airflow Network” capability that implements multizone airflow
theory, based on an earlier and limited version of AIRNET (Walton 1989) and COMIS (Feustal
and Smith 2001). Airflow Network can calculate infiltration rates arising from pressure
differences due to indoor-outdoor conditions and ventilation system operation. It can also model
ventilation and duct systems but is limited to only one air handling system per building and only
a constant volume fan. The Airflow Network capability was not incorporated into the EnergyPlus
models of the reference buildings in order to simplify modeling and reduce simulation times
(Deru et al. 2011).
As described in this report, models of the 16 reference buildings were created (new, post-1980,
and pre-1980 versions) in the current version of CONTAM (3.0) in order to perform airflow and
IAQ analyses. Together the EnergyPlus and CONTAM models allow more physically realistic
analyses of the energy and IAQ impacts of envelope airtightness and airflow-related building
retrofits and upgrades. The availability of the CONTAM models also supports the study of
technologies and approaches that can simultaneously reduce building energy consumption while
maintaining or improving IAQ.
The airflow analyses in this study included calculations of outdoor air change rates due to
infiltration only, and for the combination of mechanical ventilation and infiltration. The
relationships between these outdoor air change rates and weather conditions were also examined.
IAQ analyses included simulations of a limited set of outdoor and indoor contaminants.
Comparisons were made between airflow and energy modeling approaches, assumed and
calculated infiltration rates and their impact on sensible loads, relationships between infiltration
and weather, and contaminant concentrations relative to relevant standards and guidelines.
This report describes the building models and the results of the simulations of building airflow
and IAQ. Section 2 describes the reference buildings and compares the CONTAM and
EnergyPlus models. Section 3 describes the assumptions made in each EnergyPlus and
CONTAM model in terms of airflow. Contaminants were only modeled in CONTAM, and the
assumptions on which those simulations are based are described in Section 3.1. Section 4
presents the CONTAM airflow simulations for selected building models and compares the
results to the airflow assumptions in the EnergyPlus models, including the impacts of these
airflows on sensible loads. Section 5 presents the contaminant concentrations calculated by
CONTAM. Lastly, Section 6 discusses the results of this study as well as opportunities for
additional work.
2
2. BUILDING DESCRIPTIONS
This section provides a brief description of the reference buildings. For detailed descriptions, see
Deru et al. (2011) and Appendix A, Section A2 of this report. Table 1 lists the 16 reference
buildings and their floor area, number of floors, and number of zones in the EnergyPlus and
CONTAM models. The number of zones is different between the two models in cases where the
CONTAM models need additional zones to support more realistic airflow and IAQ analyses. For
example, zones that were added to the CONTAM models include restrooms, stairwells, elevator
shafts, and storage rooms (see Appendix A for more details). In some buildings, zones were also
resized in order to create more realistic access between adjacent zones. For instance, in the
schools, some zones were made smaller in order to create access to them from the corridor
(Appendix A, Section A2.6 and A2.7). In some buildings, “multipliers” are used in the
EnergyPlus models to indicate that the thermal load for one particular zone is to be applied to
several other ones. This technique is employed to eliminate the need to model each individual
zone in EnergyPlus. Zones with multipliers were either on the same floor or on different floors,
depending on the building configuration. An example of multiplied zones on the same floor is in
the Hospital (Appendix A, Section A2.13), where multiplied zones are located on the same floor
since each floor has a unique layout. In the office buildings, each floor has the same layout. Thus,
each zone is multiplied by the number of floors in the building. However, modeling all or at least
more of the building zones is generally important for airflow and IAQ analyses. Therefore, when
multiplied zones in EnergyPlus were on the same floor, they were modeled as one large zone in
CONTAM. When zones with multipliers were on different floors, they were modeled as separate
zones in CONTAM with leakage between them. Though zone areas and the number of zones
may be different between the EnergyPlus and CONTAM models, the total building area is
consistent between the two models. Further, the CONTAM models employed the occupancy and
outdoor air ventilation requirements that were modeled in EnergyPlus. Details on occupancy
schedules and ventilation requirements are found in Appendix A, Section A2.
3. MODELING APPROACH
EnergyPlus simulations were performed for 16 U.S. cities, which represent eight climates zones
and cover 78 % of the U.S. population (Deru et al. 2011). CONTAM simulations were only
performed using weather data from Chicago, IL, since there are a relatively high percentage of
buildings in the U.S. in this climate zone (Deru et al. 2011). Also, the system airflows calculated
by EnergyPlus for Chicago were in the mid-range of HVAC airflow rates calculated for all
16 cities. Typical meteorological year, version 2 (TMY2) weather data were obtained from DOE
(DOE 2011), which contain outdoor temperature, outdoor humidity, and wind direction and
speed. Two weather files were created for use with the CONTAM models – one for the schools
(Primary and Secondary) and the other for the remaining buildings. The difference between the
two weather files was the use of a “special day” to indicate the use of a “summer” occupancy
schedule for use in transient CONTAM simulations.
Section 3.1 presents the airflow and contaminant inputs in the CONTAM models. Section 1.1
presents the airflow inputs in the EnergyPlus models, as no contaminants were included in the
EnergyPlus models.
3
Table 1 Summary of reference buildings
No. of
floors
Floor area
(m2)
Building
No. of
EnergyPlus
zones
No. of
CONTAM
zones
Restaurants
Full service
511
1
2
Quick service
232
1
2
Health care centers
Hospital
22422
61
551
Outpatient
3804
3
1182
Hotels
Small
4013
4
672
Large
11345
6
43
Offices
Small
511
1
5
Medium
4982
3
18
Large
46320
131
731
Schools
Primary
6871
1
25
Secondary
19592
2
46
Retail
Stand-alone
2294
1
5
Strip mall
2090
1
10
Supermarket
4181
1
6
4835
1
3
Warehouse
3135
4
36
Midrise apartment
1. Includes a basement.
2. Includes a stairwell and elevator shaft.
3. Includes restroom(s) not in the EnergyPlus models.
4. Includes stairwell(s) and elevator shaft(s) not in the EnergyPlus models.
5. Includes storage rooms not in the EnergyPlus models.
33
33
641,3,4
1182
672
493,4
63
233,4
871,3,4
25
46
63
303,5
6
43
384
3.1. CONTAM model inputs
Building exterior envelope leakage was modeled in CONTAM using an effective leakage area
(AL) of 5.27 cm2/m2 at a reference pressure difference (ΔPr) of 4 Pa, a discharge coefficient (CD)
of 1.0, and a pressure exponent (n) of 0.65 for all three vintages of the reference buildings. This
leakage area value was based on consideration of airtightness data in U.S. commercial buildings
(Emmerich and Persily 2011), which does not support the use of different values for the different
vintages. This envelope leakage was applied to all above-grade exterior walls, ceilings, roofs,
and floors. Basement walls were modeled with half of the leakage specified for above grade
walls, and slab floors were modeled with no leakage. The infiltration airflow through these leaks
is calculated by CONTAM using a power-law relationship:
Q
C D AL
10000
2
ΔPr 0.5n ΔP n
ρ
4
(1)
where the indoor-outdoor pressure difference (ΔP) is calculated by CONTAM based on wind
and stack effects and ventilation equipment operation, as well as interior zone pressure
relationships. CONTAM also calculates the air density ( ) based on the temperature of the air
entering the leakage site. Detailed discussion on how CONTAM calculates these values is found
in Walton and Dols (2005). To capture the stack effect more accurately, exterior wall leakage
was divided into three portions on each wall, representing the lower third, middle third, and
upper third of each wall. Wind effects are calculated using a wind pressure profile, which
describes the wind pressure coefficients (CP) as a function of wind directions (θ). Figure 1 is the
wind pressure profile that was used (Swami and Chandra 1987). A wind speed modifier of 0.36,
which corresponds to “suburban” terrain (Walton and Dols 2005), was applied to all exterior
leakage paths.
Figure 1 Wind pressure profile simulated in CONTAM for exterior walls
θ= 0 o
330
30
CP=1.0
300
0.5
60
0.0
-0.5
-1.0
270
90
240
120
210
150
180
For openings on roofs, CP was -0.5 for all wind directions. This was an average value for roofs
with less than a 15 degree slope shown in the ASHRAE Handbook of Fundamentals, Chapter 24
(ASHRAE 2009). For buildings with attics, leakage from the roof was modeled with venting
equal to 1/150 of the floor area (Lstiburek 2006).
The effective leakage area of partitions between floors and between zones used the same value as
the exterior wall leakage (5.27 cm2/m2 at 4 Pa). The connections between zones that would not
have a physical partition, such as within an open office or retail space, were modeled as large
openings with discharge coefficient CD=0.6 and n=0.5. The size of these openings ranged from
50 % to 75 % of the wall area between zones. Transfer grilles, ranging from 0.186 m2 to
0.372 m2, and door undercuts of 0.025 m2, were modeled between restrooms and adjacent zones.
The minimum amount of outdoor ventilation air for each zone (or HVAC system) was specified
in EnergyPlus using ASHRAE 62-1999 (ASHRAE 1999). Depending on the thermal load
calculated at each time step and the indoor-outdoor conditions, EnergyPlus varied the amount of
outdoor ventilation. However, the minimum amount of outdoor ventilation air for each zone
(or HVAC system) was modeled in CONTAM with no economizer cycle to simplify the
modeling inputs. Details on the supply, return, and outdoor ventilation rates modeled in
CONTAM can be found in Appendix A.
5
The Energy Plus models have a variety of system types, ranging from through-the-wall packaged
single zone systems to variable-air volume (VAV) air handling units. All air handling units
serving multiple zones were modeled using the “simple air handling system” model in
CONTAM. The simple air handling unit components were modeled as follows:
The volume of supply ductwork was specified as 1 % of the building volume served by the
system.
The volume of return ductwork was specified as 0.5 % of the building volume served by the
system (if no return air plenum is present) and 0.25 % of the building volume served (if a
return air plenum is present).
Supply and return diffusers were located in the zones to provide the design (or maximum)
airflow rate calculated by EnergyPlus. For VAV systems included in the EnergyPlus models,
only the maximum airflow rates calculated by EnergyPlus were modeled in CONTAM.
Outdoor ventilation rates were specified at the air handling unit to provide the minimum
ventilation rate specified in EnergyPlus.
Where single-zone packaged units were modeled in EnergyPlus, a constant mass flow element
was modeled in CONTAM to add or remove the appropriate amount of outdoor air from the zone.
Constant mass flow elements were also used to represent restroom and kitchen exhaust fans.
Where these fans were included in the EnergyPlus models, those exhaust flow rates were used in
the CONTAM models. Restrooms were not included in the EnergyPlus models of the
Full Service Restaurant, Medium Office, and Stand-Alone Retail. In these buildings, restrooms
were added to the CONTAM models and the flow rates were based on ASHRAE Standard
62.1-2010 (ASHRAE 2010a).
Detailed duct models were not modeled in either CONTAM or EnergyPlus. However, for
interior restrooms (or other zones with exhaust fans), a single length of duct was used in
CONTAM to connect the restroom exhaust to the outdoors. The segment was specified with a
constant mass flow rate so that the physical characteristics of the ducts did not influence the
resulting airflow rate.
The common design goal of pressurizing commercial buildings was accounted for in the
CONTAM models by returning 90 % of the supply airflow rate. When the outdoor air quantity to
a zone was less than 10 % of the supply, the return airflow rate was equal to the supply minus the
outdoor airflow rate. For buildings with large exhaust fans, i.e., the two restaurants, the total
outdoor air intake was approximately equal to the total exhaust.
Contaminant simulations were performed for four contaminants in CONTAM: carbon dioxide
(CO2), ozone, particulates less than 2.5 μm in diameter (PM 2.5), and a generic volatile organic
compound (VOC). Table 2 summarizes the properties of these contaminants. Outdoor
concentrations of ozone and PM 2.5 were downloaded from the U.S. Environmental Protection
Agency (EPA) Air Quality Standard (AQS) database (EPA 2011a). Table 3 lists the minimum,
maximum, mean, and standard deviation of the outdoor concentration of ozone and PM 2.5 for
Chicago, IL.The outdoor concentration of CO2 was assumed to be 648 mg/m3 and that of VOC
was assumed to be zero for the CONTAM simulations.
6
Table 2 Properties of contaminants simulated in CONTAM
Contaminant
Molecular Weight Mean Diameter (μm)
CO2
44
N/A
Ozone
48
N/A
PM 2.5
N/A
0.31
3
VOC
92
N/A
1. Based on measurements in urban areas (Riley et al. 2002).
2. Equal to density of water (Chen and Zhao 2011; Riley et al. 2002).
3. Based on toluene as a representative VOC.
Effective Density (kg/m3)
N/A
N/A
1,0002
N/A
Table 3 Summary of outdoor contaminant concentrations for Chicago
Outdoor
contaminant
Ozone, μg/m3
PM 2.5, μg/m3
Daily average contaminant
concentrations
Mean Min. Max. StdDev
47
6
106
21
18
1
57
10
Daily peak contaminant
concentrations
Mean Min. Max. StdDev
80
12
155
29
30
4
94
14
Indoor contaminant sources included occupant-generated CO2 and VOCs from materials and
activities. A CO2 source was defined in all occupied zones, with an assumed generation rate of
0.3 L/min per person (ASHRAE 2010a). The maximum number of occupants specified in the
EnergyPlus models was used in the CONTAM models. The CO2 source strength in the
CONTAM models varied with occupancy based on schedules in the EnergyPlus models.
Detailed occupancy schedules for each building are found in Appendix A. An area-based VOC
source was defined in all occupied building zones. In occupied zones, a 0.5 mg/m2•h source was
included during system-on hours and reduced by 50 % during system-off hours (Persily et al.
2003). Zones that were always unoccupied had no VOC source. Deposition rates of 0.5 h-1 for
PM 2.5 (Allen et al. 2003; Howard-Reed et al. 2003; Riley et al. 2002) and 4.0 h-1 for ozone
(Kunkel et al. 2010; Nazaroff et al. 1993; Weschler 2000; Weschler et al. 1989) were included in
every zone. No indoor sources were included for ozone or PM 2.5.
A constant efficiency filter was placed in both the outdoor and recirculation air streams of all
HVAC systems in the CONTAM models (including supply air delivered by the packaged
terminal air conditioning (PTAC) units in the Small Hotel) to represent a filter placed in the
mixed air stream. The filter removed ozone at 5 % efficiency (Bekö et al. 2006) and removed
PM 2.5 at 25 % efficiency, corresponding to filters with a Minimum Efficiency Reporting Value
(MERV) of 6 as required in ASHRAE Standard 62.1-2010 (ASHRAE 2010a; Kowalski and
Bahnfleth 2002). A penetration factor of one was assumed for both ozone (Liu and Nazaroff
2001; Weschler et al. 1989) and PM 2.5 (Allen et al. 2003; Thornburg et al. 2001; Tian et al.
2009), i.e., there was no removal of these contaminants in the exterior leakage paths.
7
3.2. EnergyPlus model inputs
A simplified approach for modeling infiltration was used in the EnergyPlus models of the
reference buildings in order to simplify the assumptions needed and to reduce simulation times
(Deru et al. 2011). For the EnergyPlus models of the “new” buildings, building envelope leakage
was assumed to be 1.18 cm2/m2 at a constant indoor-outdoor pressure of 4 Pa, based on a
proposed addendum to ASHRAE 90.1-2004 for an air barrier requirement (Deru et al. 2011).
Using Equation (1), this building envelope leakage is equivalent to an airflow rate at 4 Pa of
0.000 302 m3/s•m2 of exterior surface area, which is input into the EnergyPlus models as the
building infiltration rate.
It should be noted that there is now an air barrier requirement in ASHRAE 90.1-2010 (ASHRAE
2010b), but it does not contain a whole building airtightness requirement but rather only material
and assembly tightness requirements. Note also that the value of 1.18 cm2/m2 used in the
EnergyPlus models is not necessarily consistent with expectations for buildings of this vintage
based on the existing airtightness data. However, the value of 5.27 cm2/m2 used in the CONTAM
models is supported by consideration of these data (Emmerich and Persily 2011). Besides the
building leakage value, perhaps a more important difference between the CONTAM and
EnergyPlus models is that the indoor-outdoor pressure difference across the exterior envelope is
actually calculated in CONTAM rather than assumed to be a constant 4 Pa as in the EnergyPlus
models. Assuming a constant pressure difference does not reflect known dependencies of
infiltration on indoor-outdoor pressure differences. Comparisons between the assumed
infiltration rates in EnergyPlus and those calculated by CONTAM are discussed in Section 4.
Infiltration was scheduled at 100 % of the input value when the ventilation system was scheduled
to be off and reduced to 25 % or 50 % when the ventilation system was scheduled to be on. The
exceptions to this approach were the Full Service Restaurant, Primary School, and Stand-Alone
Retail. In the Full Service Restaurant, the HVAC system was scheduled to be on from 5 a.m. to
1 a.m. However, from 12 a.m. to 1 a.m., the EnergyPlus models had infiltration scheduled at
100 % rather than a reduced value. In the Primary School, the HVAC system was scheduled to
be on from 6 a.m. to 9 p.m. However, from 6 a.m. to 7 a.m., infiltration was scheduled at 100 %
rather than a reduced value. On weekends and holidays, the Primary School HVAC system was
scheduled to always be off. On these days, infiltration was scheduled at 50 % from 7 a.m. to
9 p.m. rather than the full value. In the Stand-Alone Retail, the HVAC system was scheduled to
be on from 8 a.m. to 7 p.m. on Sundays and holidays. However, from 5 p.m. to 7 p.m.,
infiltration was scheduled at 100 % rather than a reduced value.
It should also be noted that between zones for which no physical partition would actually exist, a
physical wall (two layers of ½” gypsum) was modeled between the zones in EnergyPlus. The
walls were modeled in this way to produce temperature differences between the zones, but no
airflow between these zones was modeled in EnergyPlus. In other selected zones, a simplified
approach for interzone airflow was taken. For instance, in buildings with kitchens or dining areas,
the modeling convention was to specify a constant airflow rate from the dining area to the
kitchen area. An exhaust fan was then modeled in the dining area at a removal rate equal to this
airflow rate in order to balance flows in the zones. There was no airflow between building floors
in the EnergyPlus models.
8
In most zones of the buildings, the EnergyPlus HVAC systems were modeled with the supply
airflow rate equal to the return airflow rate. In some zones, such as dining and kitchen zones,
there was an excess of exhaust, so that the return was reduced such that the sum of the return and
exhaust equalled the supply. The effect of infiltration (either from outside or adjacent zones) on
thermal loads is considered in EnergyPlus, but infiltration is not part of the mass balance of air
into or out of the zones.
Economizer operation increased the ventilation rate above the minimum requirement when the
following conditions were met: (1) outdoor temperature less than 28 °C; (2) return temperature to
the HVAC system greater than the mixed air temperature after the outdoor air mixing box; and
(3) return temperature to the HVAC system greater than the outdoor temperature. Table 4 shows
the buildings for which at least one economizer was modeled in EnergyPlus in Chicago, IL.
Details on the economizer in EnergyPlus for each building type, vintage, and city can be found
on the DOE website (DOE 2011).
Table 4 Buildings for which economizer modeled for at least one HVAC system (Chicago)
Building
Restaurants
Full service
Quick service
Health care centers
Hospital
Outpatient
Hotels
Small
Large
Offices
Small
Medium
Large
Schools
Primary
Secondary
Retail
Stand-alone
Strip mall
Supermarket
Warehouse
Midrise apartment
Economizer
in new
building?
Economizer
in post-1980
building?
Economizer
in pre-1980
building?
Y
N
Y
N
Y
N
Y
Y
Y
Y
Y
Y
N
Y
N
Y
N
Y
N
Y
Y
N
Y
Y
N
Y
Y
Y
Y
Y
Y
Y
Y
Y
N
Y
Y
N
Y
Y
Y
Y
N
Y
Y
Y
Y
N
9
4. AIRFLOW SIMULATION RESULTS
Airflow simulations were performed for six building models representing each type of
occupancy covered by the 15 commercial reference buildings, which exclude the Midrise
Apartment building. The buildings simulated were: Full Service Restaurant, Hospital, Medium
Office, Primary School, Small Hotel, and Stand-Alone Retail. Annual simulations for the “new”
buildings were performed in both CONTAM and EnergyPlus. EnergyPlus results are presented
using two different infiltration rates. EnergyPlus results using the building envelope leakage
value assumed in Deru et al. (2011) (1.18 cm2/m2 at 4 Pa) are referred to as “EnergyPlus (tight).”
EnergyPlus results using the building envelope leakage value assumed in the CONTAM models
(5.27 cm2/m2 at 4 Pa) are referred to as “EnergyPlus (CONTAM-equivalent).”
The timestep for the CONTAM simulations was 1 hour, since the TMY2 weather data was
hourly. The timesteps for the EnergyPlus simulations were 10 minutes or 15 minutes depending
on the building. A shorter time step was used in EnergyPlus in order to better capture the effects
of heat transfer and equipment operation.
Section 4.1 presents the distribution of outdoor air change rates for the six simulated buildings,
and compares the rates calculated by CONTAM and EnergyPlus. Section 4.2 discusses the
outdoor air change rates calculated by CONTAM and EnergyPlus as a function of weather
conditions. Lastly, Section 4.3 presents the impact of infiltration on the sensible heating and
cooling loads for the six simulated buildings.
4.1. Outdoor air change rates
Outdoor air change rates were calculated as the total flow of outdoor air into the building
(including both air leakage through the exterior envelope and outdoor air intake via the
mechanical ventilation system) divided by the building volume. Attics were not included in the
building volume. It should be noted that the system is scheduled to be on when the majority of
the occupants are present in the building. The systems are generally off when the buildings are
not occupied, and in some cases, when the buildings are minimally occupied. In the Hospital and
Small Hotel, the HVAC system is always on.
Table 5 lists the number of hours under each system/fan condition, as well as the corresponding
minimum, maximum, mean, and standard deviation of the outdoor air change rates calculated by
CONTAM and EnergyPlus. The EnergyPlus values include the two assumed infiltration rates,
tight and CONTAM-equivalent. Values are listed for both system-on and system-off conditions.
“Economizer air change rates,” in the right side of Table 5, correspond to times when the HVAC
system was scheduled to be off but the controller for the economizer turned the fan on because of
suitable indoor-outdoor conditions. Economizers also operated during system-on hours, and
those air change rates are included in the system-on values in Table 5. Economizers were
modeled in all EnergyPlus models of the buildings except the Small Hotel. As noted earlier, no
economizers were modeled in CONTAM. Table 5 also lists the outdoor air change rate due to
infiltration only when the system is on. Figure 2 to Figure 7 show the frequency distribution of
outdoor air change rates for each of the six buildings for an entire year. Each figure presents the
air change rates for the various system conditions, on and off, CONTAM and Energy Plus, and
economizer operation.
10
Outdoor air change rates with system on
Table 5 shows that the Full Service Restaurant has the highest system-on outdoor air change
rates, with the following mean values: CONTAM 4.83 h-1, EnergyPlus (tight) 6.57 h-1, and
EnergyPlus (CONTAM-equiv.) 6.61 h-1. The high outdoor air change rates in the Full Service
Restaurant are due to (1) the amount of ventilation air needed as makeup air for the large kitchen
exhaust rates, and (2) high occupant density combined with the fact that the outside air supplied
per person is the third highest among the simulated buildings (Table 7 in Section 4.3). The next
highest system-on outdoor air change rates occur in the Primary School. It has a large kitchen
exhaust fan and the second highest occupant density of the simulated buildings. The Medium
Office and Hospital have the lowest system-on outdoor air change rates as calculated using
CONTAM. Low outdoor air change rates in these two buildings are due to low occupant density,
despite their having the second highest and highest, respectively, outside air supplied per person
(Table 7).
As expected, the system-on outdoor air change rates calculated using the EnergyPlus
(CONTAM-equiv.) models are higher than those calculated using the EnergyPlus (tight) models
since the infiltration rate input to the EnergyPlus (CONTAM-equiv.) models was about four
times the rate input to the EnergyPlus (tight) models. When comparing the system-on outdoor air
change rates calculated using CONTAM and the EnergyPlus models (tight and
CONTAM-equiv.), the results are different for each building.
For the Full Service Restaurant, Hospital, and Medium Office, the mean system-on outdoor air
change rates calculated using CONTAM were approximately 30 % to 40 % lower than the
EnergyPlus (tight and CONTAM-equiv.) results. For the Stand-Alone Retail, the CONTAM
results were only 4 % lower than the EnergyPlus (tight) results, but 40 % lower than the
EnergyPlus (CONTAM-equiv.) results. For the Primary School, the CONTAM results were
20 % to 40 % higher than the EnergyPlus, tight and CONTAM-equiv., results respectively. For
the Small Hotel, the CONTAM result was 60 % higher than the EnergyPlus (tight) result, but
10 % lower than the EnergyPlus (CONTAM-equiv.) result.
11
StdDev
0.30
Mean
0.23
Min.
0.22
Max.
0.23
StdDev
0.00
System-off outdoor air change rates, h-1
Hours
Mean Min. Max. StdDev
4116
0.28
0.00
0.86
0.13
3564
0.20
0.20
0.21
0.00
Economizer air change rates, h-1
552
0.34
0.21
1.09
0.20
Hours
Mean Min. Max. StdDev
2644
0.91
0.90
0.92
0.00
Economizer air change rates, h-1
1472
1.02
0.91
1.75
0.07
System-off outdoor air change rates, h-1
Hours
Mean Min. Max. StdDev
0
NA
NA
NA
NA
System-off outdoor air change rates, h-1
Hours
Mean Min. Max. StdDev
1460
0.50
0.00
1.87
0.25
1460
0.19
0.19
0.19
0.00
1435
0.87
0.87
0.88
0.00
Economizer air change rates, h-1
25
3.40
1.91
4.08
0.68
12
Note: No economizer was modeled in CONTAM. Only for the Medium Office and Primary School (EnergyPlus (tight) models) were
indoor-outdoor conditions suitable for economizer operation when the HVAC system was scheduled to be off. In addition, there was economizer
operation for the Full Service Restaurant (EnergyPlus (CONTAM-equiv.) model). The calculated air change rates of 0.00 h-1 during system-off
hours using CONTAM correspond to very small indoor-outdoor temperature differences and/or wind speeds. The values are not exactly zero but
are less than 0.005 h-1.
* T corresponds to EnergyPlus (tight) case, and CE corresponds to EnergyPlus (CONTAM-equiv.) case.
Max.
2.07
Hours
4644
EnergyPlus (CE)
CONTAM
EnergyPlus (T)
Min.
0.31
System-on infiltration rates, h-1
Mean
Min.
Max.
StdDev
0.12
0.00
0.75
0.11
0.05
0.05
0.05
0.00
System-on outdoor air change rates, h-1
Hours Mean Min. Max. StdDev
4644
0.68
0.09
1.35
0.16
4644
0.93
0.05
1.93
0.31
Medium Office
Mean
1.09
System-on infiltration rates, h-1
Mean
Min.
Max.
StdDev
0.05
0.00
0.37
0.05
0.01
0.01
0.01
0.00
0.04
0.04
0.04
0.00
System-on outdoor air change rates, h-1
Hours Mean Min. Max. StdDev
8760
0.91
0.85
1.23
0.05
8760
1.28
0.95
2.05
0.32
8760
1.32
0.99
2.20
0.32
Hospital
CONTAM
EnergyPlus (T)
EnergyPlus (CE)
System-on infiltration rates, h-1
Mean
Min.
Max.
StdDev
0.53
0.01
1.86
0.27
0.10
0.09
0.19
0.02
0.46
0.43
0.88
0.09
System-on outdoor air change rates, h-1
Hours Mean Min. Max. StdDev
7300
4.83
4.31
6.16
0.27
7300
6.57
6.27
7.28
0.20
7300
6.94
6.61
8.10
0.25
Full Service
Restaurant
CONTAM
EnergyPlus (T*)
EnergyPlus (CE)
Table 5 Summary of calculated outdoor air change rates
13
StdDev
0.06
System-on infiltration rates, h-1
Mean
Min.
Max.
StdDev
0.23
0.00
0.82
0.14
0.14
0.14
0.27
0.02
0.63
0.60
1.22
0.09
Max.
0.45
System-on outdoor air change rates, h-1
Hours Mean Min. Max. StdDev
5278
1.03
0.80
1.61
0.14
5278
1.07
0.93
1.73
0.21
5278
1.70
1.40
3.77
0.53
Min.
0.22
Stand-Alone
Retail
CONTAM
EnergyPlus (T)
EnergyPlus (CE)
Mean
0.24
CONTAM
EnergyPlus (T)
EnergyPlus (CE)
StdDev
0.19
System-on infiltration rates, h-1
Mean
Min.
Max.
StdDev
0.26
0.00
1.19
0.15
0.14
0.14
0.14
0.00
0.63
0.62
0.64
0.00
Max.
2.57
System-on outdoor air change rates, h-1
Hours Mean Min. Max. StdDev
8760
1.04
0.78
1.97
0.15
8760
0.64
0.58
0.81
0.04
8760
1.13
1.08
1.31
0.04
Min.
1.40
Small Hotel
Mean
1.55
Hours
3780
EnergyPlus (CE)
CONTAM
EnergyPlus (T)
Primary School
(Table 5 continued)
System-on outdoor air change rates, h
System-on infiltration rates, h-1
Hours Mean Min. Max. StdDev Mean
Min.
Max.
StdDev
3780
1.88
1.65
2.74
0.14
0.32
0.09
1.17
0.14
3780
1.36
1.18
2.40
0.22
0.05
0.05
0.10
0.01
-1
System-off outdoor air change rates, h-1
Hours
Mean Min. Max. StdDev
3482
0.26
0.00
0.88
0.13
3482
0.27
0.26
0.27
0.00
3482
1.21
1.20
1.23
0.00
System-off outdoor air change rates, h-1
Hours
Mean Min. Max. StdDev
0
NA
NA
NA
NA
System-off outdoor air change rates, h-1
Hours
Mean Min. Max. StdDev
4980
0.29
0.01
0.97
0.14
4032
0.08
0.05
0.10
0.02
-1
Economizer air change rates, h
948
0.22
0.06
0.77
0.09
Hours
Mean Min. Max. StdDev
3034
0.38
0.22
0.45
0.11
Economizer air change rates, h-1
1946
0.57
0.24
0.92
0.13
Table 5 shows that the mean system-on infiltration rates calculated using CONTAM were about
two to six times higher than the assumed inputs in the EnergyPlus (tight) models. For large
temperature differences and wind speeds, the corresponding system-on infiltration rates
calculated using CONTAM were as much as nine times higher than the EnergyPlus (tight) inputs.
For the Full Service Restaurant, Hospital, and Primary School, the mean system-on infiltration
rates calculated using CONTAM were also higher than the assumed inputs in the EnergyPlus
(CONTAM-equiv.) models. However, rather than roughly five times higher as in the case of the
EnergyPlus (tight) inputs, the CONTAM results were only 20 % to 30 % higher than the
EnergyPlus (CONTAM-equiv.) inputs. For the Medium Office, Small Hotel, and Stand-Alone
Retail, the mean system-on infiltration rates calculated using CONTAM were 50 % to 60 %
lower than the EnergyPlus (CONTAM-equiv.) inputs.
Because the infiltration rates in EnergyPlus were scheduled as constant values, even when the
system was on, the standard deviations of system-on infiltration rates in Table 5 are zero for
most of the buildings. The standard deviations of system-on infiltrations are greater than zero for
the Full Service Restaurant, Primary School, and Stand-Alone Retail because the system-on
infiltration rate was scheduled using two different values (Section 1.1). Even in cases where the
mean outdoor air change rates are similar, the outdoor air change rates calculated using
EnergyPlus do not reflect the dependency of infiltration on weather, while the CONTAM results
do. The impact of the differences in infiltration rates on energy consumption are discussed in
Section 4.3.
Outdoor air change rates with system off
Table 5 shows that the mean system-off outdoor air change rates calculated using the EnergyPlus
(CONTAM-equiv.) models were higher than those calculated using the EnergyPlus (tight)
models. This is expected since the infiltration rate input in the EnergyPlus (CONTAM-equiv.)
models was about four times the rate input in the EnergyPlus (tight) models.
The infiltration rates calculated by CONTAM include weather effects, unlike EnergyPlus for
which infiltration rates were scheduled as constant values. Thus, the standard deviations in Table
5 of the system-off outdoor air change rates calculated using CONTAM are greater than zero,
while those calculated using EnergyPlus are zero. The only exception is the Primary School,
where the EnergyPlus standard deviation is greater than zero because the system-off infiltration
rate was scheduled using two different values. Table 5 also shows that only for the EnergyPlus
(tight) models of the Medium Office and Primary School were conditions suitable for
economizer operation when the HVAC system was scheduled to be off. When the infiltration
rate was increased in the EnergyPlus (CONTAM-equiv.) models, the economizer was also on for
the Full Service Restaurant.
Table 5 shows that the mean system-off infiltration rates calculated using CONTAM were about
30 % to three times higher than the assumed inputs in the EnergyPlus (tight) models. An
exception is seen in the Stand Alone-Retail building, where the mean values for CONTAM and
EnergyPlus (tight) are very similar. For large temperature differences and wind speeds, the
system-on infiltration rates calculated using CONTAM were as much as five times higher than
the EnergyPlus (tight) inputs. For all buildings, the mean system-off infiltration rates calculated
14
using CONTAM were 20 % to 80 % lower than the assumed inputs in the EnergyPlus
(CONTAM-equiv.) models, independent of weather condition.
Regardless of whether the mean system-off infiltration rates calculated using CONTAM were
lower or higher than the EnergyPlus inputs, it is important to note that the infiltration rates
calculated by CONTAM take weather effects into account whereas the EnergyPlus results do not.
This is clearly seen by comparing the standard deviations in Table 5 as well as the distribution of
system-off outdoor air change rates in Figure 2 to Figure 7 (excluding the Hospital and Small
Hotel since they have 24-hour HVAC operating schedules). The solid red bars in plots (a) of
Figure 2 to Figure 7 show the variability in system-off outdoor air change rates as calculated
using CONTAM. In contrast, the solid red bars in plots (b) of Figure 2 to Figure 7 show that the
system-off outdoor air change rates calculated using EnergyPlus are constant, except for
buildings that use two different scheduled values.
For the two EnergyPlus (tight) models in which economizer operation was suitable when the
HVAC system was scheduled to be off, e.g., Medium Office and Primary School, the mean
economizer outdoor air change rates calculated using EnergyPlus (tight) were larger than the
system-off outdoor air change rates. Referring to Table 5, the number of system-off economizer
hours for the Medium Office and Primary School was about 15 % and 25 % of their respective
number of system-off hours. For the Full Service Restaurant, the increase in the assumed
infiltration rate in the EnergyPlus (CONTAM-equiv.) models resulted in 25 hours of economizer
operation, which was 2 % of the system-off hours. For the Medium Office and Primary School,
the increase in the assumed infiltration rate in the EnergyPlus (CONTAM-equiv.) models
resulted in two to three times more hours of economizer operation than in the EnergyPlus (tight)
models.
15
(a) CONTAM
Air Change Rate (h -1)
System On, CONTAM
System Off, CONTAM
0
1000
2000
3000
4000
5000
6000
(b) EnergyPlus
Air Change Rate (h-1)
Economizer, E+
(CONTAM-equiv.)
System On, E+ (tight)
System Off, E+ (tight)
System On, E+ (CONTAM-equiv.)
System Off, E+ (CONTAM-equiv.)
Economizer, E+ (CONTAM-equiv.)
0
0
(b) EnergyPlus
Air Change Rate (h-1)
System On, E+ (tight)
System On, E+ (CONTAM-equiv.)
16
Figure 3 Frequency distribution of simulated outdoor air change rates for Hospital
(a) CONTAM
1500
1500
Air Change Rate (h-1)
3000
4500
6000
7500
9000
3000
4500
6000
7500
System On, CONTAM
Figure 2 Frequency distribution of simulated outdoor air change rates for Full Service Restaurant
0
1000
2000
3000
4000
5000
6000
9000
# of Hours
# of Hours
# of Hours
# of Hours
0
1000
2000
3000
4000
5000
6000
0
1000
2000
3000
4000
5000
6000
(b) EnergyPlus
Air Change Rate (h-1)
System On, E+ (tight)
System Off, E+ (tight)
Economizer, E+ (tight)
System On, E+ (CONTAM-equiv.)
System Off, E+(CONTAM-equiv.)
Economizer, E+ (CONTAM-equiv.)
0
0
(b) EnergyPlus
Air Change Rate (h-1)
System On, E+ (tight)
System Off, E+ (tight)
Economizer, E+ (tight)
System On, E+ (CONTAM-equiv.)
System Off, E+ (CONTAM-equiv.)
Economizer, E+ (CONTAM-equiv.)
17
Figure 5 Frequency distribution of simulated outdoor air change rates for Primary School
(a) CONTAM
1000
1000
3000
4000
5000
6000
2000
Air Change Rate (h -1)
System On, CONTAM
System Off, CONTAM
Figure 4 Frequency distribution of simulated outdoor air change rates for Medium Office
(a) CONTAM
Air Change Rate (h-1)
System On, CONTAM
System Off, CONTAM
2000
3000
4000
5000
6000
# of Hours
# of Hours
# of Hours
# of Hours
# of Hours
0
1500
3000
4500
6000
7500
9000
(b) EnergyPlus
Air Change Rate (h-1)
System On, E+ (tight)
System On, E+ (CONTAM-equiv.)
0
0
(b) EnergyPlus
Air Change Rate (h-1)
System On, E+ (tight)
System Off, E+ (tight)
System On, E+ (CONTAM-equiv.)
System Off, E+ (CONTAM-equiv.)
18
Figure 7 Frequency distribution of simulated outdoor air change rates for Stand-Alone Retail
(a) CONTAM
1000
1000
3000
4000
5000
6000
2000
Air Change Rate (h-1)
System On, CONTAM
System Off, CONTAM
Figure 6 Frequency distribution of simulated outdoor air change rates for Small Hotel
(a) CONTAM
Air Change Rate (h-1)
System On, CONTAM
2000
3000
4000
5000
6000
0
1000
2000
3000
4000
5000
6000
7000
# of Hours
# of Hours
# of Hours
4.2. Outdoor air change rates vs. weather conditions
Outdoor air change rates are plotted against indoor-outdoor temperature difference, ΔT (Figure 8
to Figure 13) and wind speed, Ws (Figure 14 to Figure 19). The plots of outdoor air change rate
versus indoor-outdoor temperature difference only include air change rates for low wind speeds,
i.e., less than 2 m/s. The plots of outdoor air change rate versus wind speed are shown for
indoor-outdoor temperature differences with absolute values less than 10 oC. Limiting the plots
to low temperature differences and wind speeds makes the effects of ΔT and Ws rate easier to see.
Results are plotted for system-on, system-off, and economizer hours (where applicable).
In EnergyPlus, cooling and heating setpoints were specified for system-on and system-off hours.
Thus, the indoor temperature was not constant. When plotting the outdoor air change rates
against the indoor-outdoor temperature difference, the “indoor” temperature for the EnergyPlus
simulations were the average of the return air temperatures in the building HVAC systems. In
CONTAM, a constant indoor temperature of 20 oC was assumed.
As noted earlier, economizers were included in all of the EnergyPlus models except the Small
Hotel (Section 1.1). However, only for the Medium Office and Primary School did the
economizer operated when the HVAC system was scheduled to be off for the EnergyPlus (tight)
models. For the EnergyPlus (CONTAM-equiv.) models, economizers operated in the Full
Service Restaurant, Medium Office, and Primary School. No economizers were modeled in
CONTAM.
Outdoor air change rates vs. weather for system-on hours
Plots (a) of Figure 8 to Figure 13 show that generally there is a linear relationship between
system-on outdoor air change rates calculated using CONTAM and ΔT, with the dependence
being symmetrical about ΔT=0. However, for the Hospital, outdoor air change rates calculated
using CONTAM are not significantly affected by temperature difference as seen in Figure 9a.
The Hospital HVAC system is scheduled to always be on, and the mechanical airflows dominate
the envelope infiltration rates. Plots (a) of Figure 14 to Figure 19 show that generally there is a
non-linear relationship between system-on outdoor air change rates calculated using CONTAM
and Ws. Exceptions to these trends are discussed below.
For the Medium Office, the system-on air outdoor change rates calculated using CONTAM are
generally constant between ΔT=0 oC and ΔT=20 oC and linearly related to ΔT outside this range
(Figure 10a). Note that there is also another collection of data points on a line that is symmetrical
about ΔT=18 oC. This separate group of points exists because the system is on from 6 a.m. to
7 a.m., but outdoor air intake is not scheduled until 7 a.m. Thus, from 6 a.m. to 7 a.m., the
infiltration rates were affected by the ventilation system airflows and are shifted from the
system-off trendline. For the Primary School and Stand-Alone Retail, the system-on outdoor air
change rates calculated using CONTAM are generally constant for ΔT<0 and linearly related to
ΔT for other values (see Figure 11a and Figure 13a).
The system-on outdoor air change rates calculated using EnergyPlus are fairly constant, except
when the economizer is in operation (all buildings except Small Hotel, which had no
economizer). This increase in outdoor air change rates is clearly observed in the plots of outdoor
air change rate vs. ΔT (plots (b) of Figure 8 to Figure 11 and Figure 13b). No relationship is seen
19
between the system-on outdoor air change rates calculated using EnergyPlus and Ws (plots (b) of
Figure 14 to Figure 19). There is also little difference between the system-on outdoor air change
rates calculated using the EnergyPlus (CONTAM-equiv.) and EnergyPlus (tight) models except
for the Small Hotel (Figure 12b) and Stand-Alone Retail (Figure 13b). The dependencies on
temperature difference and wind speed, however, were not affected.
Outdoor air change rates vs. weather for system-off hours
Plots (a) of Figure 8 to Figure 13 show that generally there is a linear relationship between
system-off outdoor air change rates calculated using CONTAM and ΔT, with the dependence
being symmetrical about ΔT=0. This is expected since the stack effect is driven by air density,
i.e., air temperature, differences between indoors and outdoors. Plots (a) of Figure 14 to
Figure 19 show that generally there is a non-linear relationship between system-off outdoor air
change rates calculated using CONTAM and Ws. This dependence is expected since indooroutdoor pressure differences due to wind are related to the square of the wind speed.
There is approximately a four-fold increase in system-off outdoor air changes rates using the
EnergyPlus (CONTAM-equiv.) models compared to the EnergyPlus (tight) models, as reflected
in plots (b) of Figure 8 to Figure 13. Since infiltration is a scheduled input in the EnergyPlus
models (Section 1.1), the system-off air outdoor change rates calculated using EnergyPlus are
constant, whether plotted against ΔT or Ws. Only for the Medium Office and Primary School
were the conditions suitable for economizer operation when the HVAC system was scheduled to
be off for the EnergyPlus (tight) models. During system-off economizer operation in the Medium
Office (Figure 10b) and Primary School (Figure 11b), the outdoor air change rates calculated
using EnergyPlus were higher (indicated by black triangles) than the system-off air change rates
(indicated by blue x’s). Generally, the economizer was in operation for -10 oC <ΔT<20 oC. Note
that Figure 10 and Figure 11 show only the outdoor air change rates when the wind speed was
less than 2 m/s. In addition to the Medium Office and Primary School, economizers also
operated in the Full Service Restaurant for the EnergyPlus (CONTAM-equiv.) models
(Figure 8b). During system-off economizer operation, the outdoor air change rates calculated
using the EnergyPlus (CONTAM-equiv.) model were higher (indicated by orange triangles) than
the system-off outdoor air change rates (indicated by red stars).
20
Air change rate (h-1)
0.0
1.5
3.0
4.5
6.0
-20
(a) CONTAM
-10
0
10
20
30
Indoor-outdoor temperature difference (oC)
System on, CONTAM
System off, CONTAM
Indoor-outdoor temperature difference (oF)
-18
0
18
36
54
40
72
0.0
1.5
3.0
4.5
6.0
7.5
-20
-36
(b) EnergyPlus
-10
0
10
20
30
Indoor-outdoor temperature difference (oC)
System on, E+ (tight)
System off, E+ (tight)
System on, E+ (CONTAM-equiv.)
System off, E+ (CONTAM-equiv.)
Economizer, E+ (CONTAM-equiv.)
Indoor-outdoor temperature difference (oF)
-18
0
18
36
54
40
72
-20
-36
(b) EnergyPlus
-10
0
10
20
30
Indoor-outdoor temperature difference (oC)
System on, E+ (tight)
System on, E+ (CONTAM-equiv.)
Indoor-outdoor temperature difference (oF)
-18
0
18
36
54
21
Figure 9 Air change rates as a function of temperature difference (low wind speed) for Hospital
(a) CONTAM
0.0
40
1.0
1.5
2.0
2.5
3.0
0.0
-10
0
10
20
30
Indoor-outdoor temperature difference (oC)
72
0.5
-20
System on, CONTAM
Indoor-outdoor temperature difference (oF)
-18
0
18
36
54
0.5
1.0
1.5
2.0
2.5
3.0
-36
40
72
Figure 8 Air change rates as a function of temperature difference (low wind speed) for Full Service Restaurant
Air change rate (h-1)
7.5
-36
Air change rate (h-1)
Air change rate (h-1)
0.0
0.5
1.0
1.5
2.0
2.5
-20
(a) CONTAM
-10
0
10
20
30
Indoor-outdoor temperature difference (oC)
System on, CONTAM
System off, CONTAM
Indoor-outdoor temperature difference (oF)
-18
0
18
36
54
40
72
0.0
0.5
1.0
1.5
2.0
2.5
3.0
-20
-36
(b) EnergyPlus
-10
0
10
20
30
Indoor-outdoor temperature difference (oC)
System on, E+ (tight)
System off, E+ (tight)
Economizer, E+ (tight)
System on, E+ (CONTAM-equiv.)
System off, E+ (CONTAM-equiv.)
Economizer, E+ (CONTAM-equiv.)
Indoor-outdoor temperature difference (oF)
-18
0
18
36
54
40
72
(a) CONTAM
0.0
40
1.0
1.5
2.0
2.5
3.0
0.0
-10
0
10
20
30
Indoor-outdoor temperature difference (oC)
72
0.5
-20
System on, CONTAM
System off, CONTAM
Indoor-outdoor temperature difference (oF)
-18
0
18
36
54
0.5
1.0
1.5
2.0
2.5
3.0
-36
-20
-36
(b) EnergyPlus
-10
0
10
20
30
Indoor-outdoor temperature difference (oC)
System on, E+ (tight)
System off, E+ (tight)
Economizer, E+ (tight)
System on, E+ (CONTAM-equiv.)
System off, E+ (CONTAM-equiv.)
Economizer, E+ (CONTAM-equiv.)
Indoor-outdoor temperature difference (oF)
-18
0
18
36
54
40
72
22
Figure 11 Air change rates as a function of temperature difference (low wind speed) for Primary School
Air change rate (h-1)
Figure 10 Air change rates as a function of temperature difference (low wind speed) for Medium Office
Air change rate (h-1)
3.0
-36
Air change rate (h-1)
Air change rate (h-1)
0.0
0.5
1.0
1.5
2.0
2.5
-20
(a) CONTAM
-10
0
10
20
30
Indoor-outdoor temperature difference (oC)
System on, CONTAM
Indoor-outdoor temperature difference (oF)
-18
0
18
36
54
40
72
0.0
0.5
1.0
1.5
2.0
2.5
3.0
-20
-36
(b) EnergyPlus
-10
0
10
20
30
Indoor-outdoor temperature difference (oC)
System on, E+ (tight)
System on, E+ (CONTAM-equiv.)
Indoor-outdoor temperature difference (oF)
-18
0
18
36
54
(a) CONTAM
0.0
40
1.0
1.5
2.0
2.5
3.0
0.0
-10
0
10
20
30
Indoor-outdoor temperature difference (oC)
72
0.5
-20
System on, CONTAM
System off, CONTAM
Indoor-outdoor temperature difference (oF)
-18
0
18
36
54
0.5
1.0
1.5
2.0
2.5
3.0
-36
-20
-36
(b) EnergyPlus
-10
0
10
20
30
Indoor-outdoor temperature difference (oC)
System on, E+ (tight)
System off, E+ (tight)
System on, E+ (CONTAM-equiv.)
System off, E+ (CONTAM-equiv.)
Indoor-outdoor temperature difference (oF)
-18
0
18
36
54
40
72
40
72
23
Figure 13 Air change rates as a function of temperature difference (low wind speed) for Stand-Alone Retail
Air change rate (h-1)
Figure 12 Air change rates as a function of temperature difference (low wind speed) for Small Hotel
Air change rate (h-1)
3.0
-36
Air change rate (h-1)
Air change rate (h-1)
Air change rate (h-1)
Air change rate (h-1)
(a) CONTAM
8
Wind speed (m/s)
12
30
16
36
0.0
1.5
3.0
4.5
6.0
7.5
0
0
12
Wind speed (mph)
18
24
4
(b) EnergyPlus
8
Wind speed (m/s)
System on, E+ (tight)
System off, E+ (tight)
System on, E+ (CONTAM-equiv.)
System off, E+ (CONTAM-equiv.)
Economizer, E+ (CONTAM-equiv.)
6
12
30
12
12
30
16
36
1.0
1.5
2.0
2.5
3.0
0
0
12
Wind speed (mph)
18
24
4
(b) EnergyPlus
8
Wind speed (m/s)
System on, E+ (tight)
System on, E+ (CONTAM-equiv.)
6
24
Figure 15 Air change rates as a function of wind speed (low ΔT) for Hospital
(a) CONTAM
0.0
8
Wind speed (m/s)
Wind speed (mph)
18
24
0.0
4
System on, CONTAM
6
12
30
Figure 14 Air change rates as a function of wind speed (low ΔT) for Full Service Restaurant
4
Wind speed (mph)
18
24
0.5
0
0
0
12
System on, CONTAM
System off, CONTAM
6
0.5
1.0
1.5
2.0
2.5
3.0
0.0
1.5
3.0
4.5
6.0
7.5
0
Air change rate (h-1)
Air change rate (h-1)
16
36
16
36
Air change rate (h-1)
Air change rate (h-1)
(a) CONTAM
8
Wind speed (m/s)
12
30
16
36
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0
0
6
4
12
12
30
16
36
1.0
1.5
2.0
2.5
3.0
8
Wind speed (m/s)
12
0
0
6
4
25
30
8
Wind speed (m/s)
12
System on, E+ (tight)
System off, E+ (tight)
Economizer, E+ (tight)
System on, E+ (CONTAM-equiv.)
System off, E+ (CONTAM-equiv.)
Economizer, E+ (CONTAM-equiv.)
Wind speed (mph)
18
24
(b) EnergyPlus
12
Figure 17 Air change rates as a function of wind speed (low ΔT) for Primary School
(a) CONTAM
0.0
8
Wind speed (m/s)
Wind speed (mph)
18
24
0.0
4
System on, CONTAM
System off, CONTAM
6
30
System on, E+ (tight)
System off, E+ (tight)
Economizer, E+ (tight)
System on, E+ (CONTAM-equiv.)
System off, E+ (CONTAM-equiv.)
Economizer, E+ (CONTAM-equiv.)
Wind speed (mph)
18
24
(b) EnergyPlus
12
Figure 16 Air change rates as a function of wind speed (low ΔT) for Medium Office
4
Wind speed (mph)
18
24
0.5
0
0
0
12
System on, CONTAM
System off, CONTAM
6
0.5
1.0
1.5
2.0
2.5
3.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0
Air change rate (h-1)
Air change rate (h-1)
16
36
16
36
Air change rate (h-1)
Air change rate (h-1)
(a) CONTAM
8
Wind speed (m/s)
12
30
16
36
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0
0
12
Wind speed (mph)
18
24
4
(b) EnergyPlus
8
Wind speed (m/s)
System on, E+ (tight)
System on, E+ (CONTAM-equiv.)
6
12
12
30
16
36
1.0
1.5
2.0
2.5
3.0
0
0
6
4
26
30
30
8
Wind speed (m/s)
12
System on, E+ (tight)
System off, E+ (tight)
System on, E+ (CONTAM-equiv.)
System off, E+ (CONTAM-equiv.)
Wind speed (mph)
18
24
(b) EnergyPlus
12
12
Figure 19 Air change rates as a function of wind speed (low ΔT) for Stand-Alone Retail
(a) CONTAM
0.0
8
Wind speed (m/s)
Wind speed (mph)
18
24
0.0
4
System on, CONTAM
System off, CONTAM
6
Figure 18 Air change rates as a function of wind speed (low ΔT) for Small Hotel
4
Wind speed (mph)
18
24
0.5
0
0
0
12
System on, CONTAM
6
0.5
1.0
1.5
2.0
2.5
3.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0
Air change rate (h-1)
Air change rate (h-1)
16
36
16
36
4.3. Impacts of infiltration on sensible load
As discussed in Section 4.1 and 4.2, there are a significant number of hours out of the year for
which the infiltration rates calculated using CONTAM are higher than those calculated using
EnergyPlus. This section describes the impact of those higher rates on the sensible heating and
cooling loads in the six simulated buildings. The sensible load, qs in kJ, associated with
infiltration is calculated by:
qs = ρCPIV(Toutdoor – Tindoor) x 1 h
(2)
where CP is the specific heat of air in kJ/kg, I is the air change rate due to infiltration in h-1,
Tindoor is the average indoor temperature of all zones in K, Toutdoor is the outdoor temperature in K,
and V is the volume of the building in m3. When Toutdoor is less than Tindoor, qs will be negative and
thus there is a sensible heating load. Conversely, when Toutdoor is greater than Tindoor, qs will be
positive and there is a sensible cooling load.
Table 6 lists the total heating and cooling sensible loads due to infiltration in each building in GJ
for one year of Chicago weather conditions. These estimates do not account for any other loads,
internal or external, or HVAC system effects and efficiencies in meeting these loads. The
columns in Table 6 contain the sensible load due to infiltration using the EnergyPlus (tight and
CONTAM-equiv. models) infiltration rates, the sensible load using the infiltration rates from
CONTAM, and the ratios of the CONTAM infiltration sensible load to the EnergyPlus (tight and
CONTAM-equiv. models) infiltration load.
Table 6 Sensible loads due to infiltration
Building
Full Service
Restaurant
Hospital
Medium
Office
Primary
School
Small Hotel
Stand-Alone
Retail
Load
EnergyPlus
(tight) (GJ)
EnergyPlus
(CONTAM
-equiv.)
(GJ)
Heating
Cooling
Heating
Cooling
Heating
Cooling
Heating
Cooling
Heating
Cooling
Heating
Cooling
27
0.4
100
8
310
4
221
19
230
6
333
7
115
2
454
36
1178
16
1083
18
1010
27
1379
32
CONTAM
(GJ)
Ratio of
CONTAM to
EnergyPlus
(tight)
128
6
898
22
611
23
1248
62
479
22
559
20
4.8
13.6
9.0
2.7
2.0
6.6
5.7
3.2
2.1
3.7
1.7
2.6
Ratio of
CONTAM to
EnergyPlus
(CONTAMequiv.)
1.1
3.0
2.0
0.6
0.5
1.4
1.2
3.4
0.5
0.8
0.4
0.6
In general, the infiltration sensible heating loads are greater than the cooling loads, whether
calculated by EnergyPlus or CONTAM. This is to be expected since the simulations were
performed using Chicago weather. The infiltration heating loads calculated using CONTAM are
about two to nine times higher than the EnergyPlus (tight) results. In the Full Service Restaurant,
Hospital, and Primary School, the infiltration sensible heating loads calculated using CONTAM
27
are also higher than the EnergyPlus (CONTAM-equiv.) results. However, rather than two to nine
times higher than the EnergyPlus (tight) results, the CONTAM results were only 10 % to two
times higher than the EnergyPlus (CONTAM-equiv.) results. For the Medium Office, Small
Hotel, and Stand-Alone Retail, the infiltration load calculated using CONTAM is 50 % to 60 %
lower than the EnergyPlus (CONTAM-equiv.) results. As discussed in Section 4.1, in these three
buildings, the CONTAM system-on or system-off infiltration rates, in some cases both, were
lower than the EnergyPlus (CONTAM-equiv.) results. Note that these loads only accounted for
the heating and cooling of the infiltration air and do not include latent loads, system effects or
internal loads.
The infiltration cooling loads calculated using CONTAM were about three to 10 times higher
than the EnergyPlus (tight) results. However, for the Full Service Restaurant, the cooling load
was 14 times higher than the EnergyPlus (tight) results, largely due to the fact that the
EnergyPlus (tight) infiltration sensible cooling load was very small, 0.4 GJ. In the Full Service
Restaurant, Medium Office, and Primary School, the infiltration sensible cooling loads
calculated using CONTAM were also higher than the EnergyPlus (CONTAM-equiv.) results.
However, rather than three to 10 times higher than the EnergyPlus (tight) results, the CONTAM
results were only 40 % to three times higher than the EnergyPlus (CONTAM-equiv.) results. For
the Hospital, Small Hotel, and Stand-Alone Retail, the infiltration sensible cooling load
calculated using CONTAM was 20 % to 40 % lower than the EnergyPlus (CONTAM-equiv.)
results. As discussed in Section 4.1, both the CONTAM system-on and system-off infiltration
rates for the Small Hotel and Stand-Alone Retail were lower than the EnergyPlus (CONTAMequiv.) results.
For all of the buildings, except the Hospital, the differences in calculated infiltration sensible
load between the CONTAM and EnergyPlus (tight) models were 10 % to 60 % of the total
energy consumption. For the Hospital, the differences in calculated infiltration sensible load
were only 1 % to 5 % of the total energy consumption because the energy consumption for the
Hospital is the highest among the six simulated buildings. Although the infiltration sensible loads
calculated using the EnergyPlus (CONTAM-equiv.) models were closer to the CONTAM values,
there were still 10 % to 50 % differences between CONTAM and EnergyPlus (CONTAM-equiv.)
results.
Note that the values in Table 6 are total sensible loads over one year and that the differences
between the CONTAM- and EnergyPlus loads are more significant for individual hours when the
weather conditions lead to higher infiltration rates. All of these differences point out the
importance of accurate modeling of building airflow in building energy simulation.
28
5. CONTAMINANT SIMULATION RESULTS
This section presents the contaminant simulation results for system-on hours only, during which
the majority of the occupants are present. The distribution of daily average concentrations of all
contaminants, distribution of daily peak CO2 concentrations, and distribution of daily peak
volatile organic compounds (VOC) concentrations are plotted in Figure 20 to Figure 37 for the
selected zones listed in Table 7 for each of the six buildings. Detailed results can be found in
Appendix B. Table 7 also lists the total maximum occupancy in those zones, the total zone
occupancy divided by the floor area of the zones, and the average outdoor air intake per person
for the zones. For the Full Service Restaurant and Stand-Alone Retail, the only zone for which
results are not presented is for the restroom because it is not generally occupied. For the
remaining buildings, the zones were selected to represent various occupancy types and densities
within the building. Zones were also selected based on location within the building to represent
different exposures to weather conditions. For instance, in the Medium Office, both the West and
South Perimeter zones were selected since they would be exposed to different wind conditions.
In the Medium Office and Small Hotel, similar zones were selected on each floor in order to
observe the differences in contaminant concentrations due to elevation. As seen in Table 7, the
highest occupancy density in the Full Service Restaurant, while the Hospital and Medium Office
are almost a factor of ten lower. The outdoor air intake rates per person are similar for all the
buildings, except for the Hospital, for which they are much higher due to the higher ventilation
requirements in healthcare facilities. Table 8 lists the minimum and maximum daily average and
daily peak indoor concentration for each contaminant based on the zones listed in Table 7. Thus,
the values in Table 8 do not reflect overall minimum and maximum for the entire building but
only for those zones. Detailed minimums, maximums, means and standard deviations of the
indoor concentrations for each zone in each building are in Appendix B. Figure 20 to Figure 25
show the distribution frequency of CO2 concentration for each selected zone in each of the six
buildings for the entire year. Figure 26 to Figure 31 show the distribution frequency of VOC
concentration for each selected zone. Figure 32 to Figure 37 show the distribution frequency of
ozone and PM 2.5 concentration for each selected zone.
The Full Service Restaurant and Primary School are among the buildings with the highest indoor
ozone and PM 2.5 concentrations as shown in Table 8, but the differences are not exceptionally
large. The only source of ozone and PM 2.5 is the outdoor air, and their indoor deposition rates
are related to zone size. Thus, the slightly higher indoor ozone and PM 2.5 concentrations in
these two buildings occur primarily due to the higher air change rates that bring in more ozone
and PM 2.5. In contrast, the Hospital and Medium Office are among the buildings with the
lowest indoor ozone and PM 2.5 concentrations. This is due primarily to the lower air change
rates that bring in less ozone and PM 2.5.
Table 8 also shows that the Hospital and Medium Office have the highest indoor VOC
concentrations. Because the VOC sources are area-based, the primary factor in determining the
indoor concentrations are the outdoor air intake rates per unit floor area. The Hopstial and
Medicum Office have the lowest values of the outdoor air intake per floor area, leading to the
highest VOC concentrations. In contrast, the Primary School, Small Hotel, and Stand-Alone
Retail have higher outdoor air intake rates per floor area, leading to lower indoor VOC
concentrations.
29
Table 7 Selected zones for which contaminant concentration results reported
Building
Selected zones
Full
Service
Restaurant
Dining
Kitchen
1F ER Exam 3
1F ER Nurse’s
Station
1F Lobby
2F ICU
2F ICU Patient Rm 3
2F Operating Rm 2
1-3F Core Zone
1-3F West Perimeter
Cafeteria
Gym
Library/Media
Classroom
3F Lab
3F Nurse’s Station
Lobby
3F Patient Rm 3
3F Patient Rm 4
5F Dining
5F Office 2
1-3F South
Perimeter
Offices
Pod 1 Corner
Classroom 1
Pod 1 Multiple
Classroom 1
Guest 409-412
Guest 215-218
Guest 315-318
Guest 415-318
Front Retail
Point of Sale
Hospital
Medium
Office
Primary
School
Small
Hotel
Front Lounge
Meeting Room
Guest 209-212
Guest 309-312
Back Space
Core Retail
Total max.
occupancy
in selected
zones1
274
Max.
occupancy
per floor area
(per 100 m2)1
55
Average
outdoor air
intake
(L/s•person)2
10.0
259
4
27.1
213
6
11.9
591
29
9.4
129
13
9.2
Stand321
14
9.8
Alone
Retail
Notes:
1. Maximum occupancy and occupancy per floor area are based only on the selected zones.
2. Values are sum of L/s supplied to all of the selected zones divided by the sum of the number of
occupants in the selected zones.
30
Table 8 Summary of calculated contaminant concentrations
Full Service
Restaurant
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Hospital
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Medium Office
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Primary School
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Small Hotel
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Stand-Alone Retail
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Daily average contaminant
concentrations
Min.
Max.
1020
1579
3
62
1
42
27
62
Daily average contaminant
concentrations
Min.
Max.
749
991
1
40
<1
24
38
242
Daily average contaminant
concentrations
Min.
Max.
826
1219
1
34
<1
23
75
291
Daily average contaminant
concentrations
Min.
Max.
793
1279
2
74
<1
52
15
172
Daily average contaminant
concentrations
Min.
Max.
759
1054
1
61
<1
41
16
282
Daily average contaminant
concentrations
Min.
Max.
741
1173
1
43
<1
32
20
180
Daily peak contaminant
concentrations
Min.
Max.
1352
2433
5
86
2
61
31
343
Daily peak contaminant
concentrations
Min.
Max.
759
1145
1
58
1
33
42
243
Daily peak contaminant
concentrations
Min.
Max.
887
1416
2
57
1
32
104
812
Daily peak contaminant
concentrations
Min.
Max.
820
1683
5
98
1
68
34
1186
Daily peak contaminant
concentrations
Min.
Max.
847
1363
1
89
1
60
22
306
Daily peak contaminant
concentrations
Min.
Max.
757
1486
2
68
1
45
24
436
Note: The “Min.” and “Max.” values only apply to the zones in each building for which contaminant concentrations
are reported (see Table 7 for selected zones).
31
Figure 20 to Figure 25 show the average and peak CO2 concentrations for the six simulated
buildings. The differences in these values among the selected zones reflect variations in occupant
density and outdoor air intake per person. For example, Figure 24a shows that the guestrooms in
the Small Hotel have higher daily average CO2 concentrations than the Front Lounge and
Meeting Room even though the maximum occupancies in the guestrooms are less. This is
because the Front Lounge and Meeting Room are occupied less during the day than the
guestrooms, resulting in less total CO2 being generated in those spaces. Further, the Front
Lounge and Meeting Room also have higher outdoor air requirements. Figure 24b shows that the
daily peak CO2 concentrations in the Front Lounge and Meeting Room are larger than those in
the guestrooms because they have the largest maximum occupancy of the selected zones.
In general, Figure 26 to Figure 31 show that the distribution of indoor VOC concentrations
among selected zones is similar in most buildings. Larger differences are seen for the Hospital
(Figure 27) and Small Hotel (Figure 30). In the Hospital, the first floor ER Exam 3 and second
floor OR 2 have lower daily average and peak VOC concentrations compared to the other
selected zones. This is due to less VOC being generated inside these smaller zones, and the
outside air requirements in these zones are among the highest of the selected zones. Figure 30
shows that the daily average and peak VOC concentrations in the Front Lounge and Meeting
Room in the Small Hotel are less than those in the guestrooms. This is the case because the
outside air requirements in these zones are much higher than in the guestrooms, even though the
Front Lounge and Meeting Room are larger than the guestrooms in terms of floor area.
In general, Figure 32 to Figure 37 show that the distribution of indoor ozone and PM 2.5
concentrations among selected zones is similar within each simulated building. This was to be
expected since (1) the only source of ozone and PM 2.5 was the outdoors, and (2) differences in
how much ozone and PM 2.5 enter these zones from the outdoors (air change rates based on zone
volume) were counterbalanced by differences in deposition of these contaminants also based on
zone volume. Indoor ozone and PM 2.5 concentrations are lower than the outdoor concentrations
for all simulated buildings due to deposition and filtration.
Based on the 2010 ozone data from the EPA AQS database (EPA 2011a) used in these
simulations for Chicago, there were only 4 hours during the year (8760 total hours) for which the
outdoor ozone level exceeded the National Ambient Air Quality Standards (NAAQS) limit of
150 μg/m3 (EPA 2011b). The World Health Organization (WHO) indoor guideline for ozone is
100 μg/m3 (WHO 2005). There were no hours for which the indoor ozone level exceeded
100 μg/m3 in any of the selected zones in the buildings. Table 8 shows that of the selected zones
in the simulated buildings, the maximum daily peak ozone concentration was 98 μg/m3.
Based on the 2010 PM 2.5 data from the EPA Air Quality Standard (AQS) database (EPA 2011a)
used in these simulations for Chicago, there were 868 hours during the year for which the
outdoor PM 2.5 level exceeded the NAAQS limit of 35 μg/m3 (EPA 2011b). The WHO indoor
guidelines for PM 2.5 are 10 μg/m3, 15 μg/m3, 25 μg/m3, or 35 μg/m3 based on the level of risk
tolerance (WHO 2005). The number of hours the indoor PM2.5 level exceeded the WHO limit of
35 μg/m3, was different in each simulated building. In the Full Service Restaurant, there were
122 hours for which the indoor PM 2.5 level exceeded 35 μg/m3 in the Kitchen. In the Primary
School, there were 220 hours for which the indoor PM 2.5 level exceeded 35 μg/m3 in the
32
Cafeteria. The maximum number of hours for which the indoor PM 2.5 level exceeded the WHO
limit in the Small Hotel was 142 (in the Meeting Room). The maximum number of hours for
which the indoor PM 2.5 level exceeded the WHO limit in the Stand-Alone Retail was 16 (in the
Back Space). There were no hours for which the indoor PM 2.5 level exceeded the WHO limit in
the Medium Office and Hospital.
In the Medium Office and Small Hotel, similar zones were selected on multiple floors in order to
observe the differences in contaminants due to elevation. For the indoor contaminants studied in
this report, the distributions of concentration remained relatively the same independent of zone
location or elevation. This result was perhaps due to the fact that the Medium Office was only
three stories and the Small Hotel was only four stories. In taller buildings with a stronger stack
effect, there might be more significant concentration gradients with elevation.
33
0
50
100
150
200
250
300
350
400
1400
(a) Daily averages
1300
1300
1200
1200
1100
1100
1000
1000
900
900
800
800
700
700
34
Figure 20 Frequency distribution of simulated CO2 concentration for Full Service Restaurant
(b) Daily peaks
Peak CO2 concentration (mg/m3)
1400
Average CO2 concentration (mg/m3)
1500
1500
0
1600
1600
50
1700
1700
100
1800
1800
150
1900
1900
200
2000
2000
250
2100
2100
300
2200
2200
350
2300
2300
400
Kitchen
Dining
Kitchen
Dining
2400
2400
# of Days
# of Days
2500
2500
0
50
100
150
200
250
300
350
400
800
800
700
700
5th Flr Dining Room
3rd Flr Nurse Stn. Lobby
3rd Flr Patient Room 3
2nd Flr OR 2
1st Flr ER Nurse Stn.
(a) Daily averages
(b) Daily peaks
Peak CO2 concentration (mg/m3)
5th Flr Dining Room
3rd Flr Nurse Stn. Lobby
3rd Flr Patient Room 3
2nd Flr OR 2
1st Flr ER Nurse Stn.
1st Flr Lobby
Average CO2 concentration (mg/m3)
5th Flr Office 2
3rd Flr Patient Room 4
3rd Flr Lab
2nd Flr ICU
2nd Flr ICU Patient Room 3
1st Flr ER Exam 3
5th Flr Office 2
3rd Flr Patient Room 4
3rd Flr Lab
2nd Flr ICU
2nd Flr ICU Patient Room 3
1st Flr ER Exam 3
35
Figure 21 Frequency distribution of simulated CO2 concentration for Hospital
900
900
0
1000
1000
50
1100
1100
100
1200
1200
150
1300
1300
200
1400
1400
250
1500
1500
300
1600
1600
350
1700
1700
400
1800
# of Days
# of Days
1800
1st Flr Lobby
2200
2200
1900
1900
2300
2300
2000
2000
2400
2400
2100
2100
2500
2500
0
50
100
150
200
250
300
350
400
1100
1100
1000
1000
900
900
800
800
700
700
(a) Daily averages
Average CO2 concentration (mg/m3)
(b) Daily peaks
Peak CO2 concentration (mg/m3)
3rd Flr Core
3rd Flr South
2nd Flr West
1st Flr Core
1st Flr South
3rd Flr Core
3rd Flr South
2nd Flr West
1st Flr Core
1st Flr South
36
Figure 22 Frequency distribution of simulated CO2 concentration for Medium Office
1200
1200
0
1300
1300
50
1400
1400
100
1500
1500
150
1600
1600
200
1700
1700
250
1800
1800
300
1900
1900
350
2000
2000
400
2300
2300
# of Days
# of Days
2100
2100
3rd Flr West
2nd Flr Core
2nd Flr South
1st Flr West
3rd Flr West
2nd Flr Core
2nd Flr South
1st Flr West
2400
2400
2200
2200
2500
2500
0
50
100
150
200
250
300
350
400
(a) Daily averages
Average CO2 concentration (mg/m3)
1500
1400
1400
1300
1300
1200
1200
1100
1100
1000
1000
900
900
800
800
700
700
# of Days
Library/Media
Cafeteria
Gym
Offices
Corner Class 1 Pod 1
Mult Class 1 Pod1
Library/Media
Cafeteria
Gym
Offices
Corner Class 1 Pod 1
Mult Class 1 Pod1
37
Figure 23 Frequency distribution of simulated CO2 concentration for Primary School
(b) Daily peaks
Peak CO2 concentration (mg/m3)
1500
0
1600
1600
50
1700
1700
100
1800
1800
150
1900
1900
200
2000
2000
250
2100
2100
300
2200
2200
350
2300
2300
# of Days
2400
2400
400
2500
2500
0
50
100
150
200
250
300
350
400
1100
1100
1000
1000
900
900
800
800
700
700
(a) Daily averages
Average CO2 concentration (mg/m3)
(b) Daily peaks
Peak CO2 concentration (mg/m3)
Guest 315-318
Guest 409-412
Guest 209-212
Front Lounge
Guest 315-318
Guest 409-412
Guest 209-212
Front Lounge
38
Figure 24 Frequency distribution of simulated CO2 concentration for Small Hotel
1200
1200
0
1300
1300
50
1400
1400
100
1500
1500
150
1600
1600
200
1700
1700
250
1800
1800
300
1900
1900
350
2000
2000
400
2300
2300
# of Days
# of Days
2100
2100
Guest 415-418
Guest 215-218
Guest 309-312
Meeting Room
Guest 415-418
Guest 215-218
Guest 309-312
Meeting Room
2400
2400
2200
2200
2500
2500
0
50
100
150
200
250
300
350
400
1400
(a) Daily averages
1300
1300
1200
1200
1100
1100
1000
1000
900
900
800
800
700
700
39
Figure 25 Frequency distribution of simulated CO2 concentration for Stand-Alone Retail
(b) Daily peaks
Peak CO2 concentration (mg/m3)
1400
Average CO2 concentration (mg/m3)
1500
1500
0
1600
1600
50
1700
1700
100
1800
1800
150
1900
1900
200
2000
2000
250
2100
2100
300
2200
2200
350
2300
2300
400
Back Space
Core Retail
Front Retail
Point of Sale
Back Space
Core Retail
Front Retail
Point of Sale
2400
2400
# of Days
# of Days
2500
2500
0
50
100
150
200
250
300
350
400
450
400
(a) Daily averages
(b) Daily peaks
Peak VOC concentration ( g/m3)
450
350
350
300
300
250
250
200
200
150
150
100
100
50
50
Kitchen
Dining
Kitchen
Dining
40
Figure 26 Frequency distribution of simulated VOC concentration for Full Service Restaurant
400
Average VOC concentration ( g/m3)
500
500
0
550
550
50
600
600
100
650
650
150
700
700
200
750
750
250
800
800
300
850
850
350
900
900
# of Days
# of Days
950
950
400
1000
1000
0
50
100
150
200
250
300
350
400
100
100
50
50
(a) Daily averages
(b) Daily peaks
Peak VOC concentration ( g/m3)
5th Flr Dining Room
3rd Flr Nurse Stn. Lobby
3rd Flr Patient Room 3
2nd Flr OR 2
1st Flr ER Nurse Stn.
1st Flr Lobby
Average VOC concentration ( g/m3)
5th Flr Dining Room
3rd Flr Nurse Stn. Lobby
3rd Flr Patient Room 3
2nd Flr OR 2
1st Flr ER Nurse Stn.
1st Flr Lobby
5th Flr Office 2
3rd Flr Patient Room 4
3rd Flr Lab
2nd Flr ICU
2nd Flr ICU Patient Room 3
1st Flr ER Exam 3
5th Flr Office 2
3rd Flr Patient Room 4
3rd Flr Lab
2nd Flr ICU
2nd Flr ICU Patient Room 3
1st Flr ER Exam 3
41
Figure 27 Frequency distribution of simulated VOC concentration for Hospital
150
150
0
200
200
50
250
250
100
300
300
150
350
350
200
400
400
250
450
450
300
500
500
350
600
600
# of Days
# of Days
650
650
400
850
850
550
550
700
700
900
900
750
750
950
950
800
800
1000
1000
0
50
100
150
200
250
300
350
400
300
300
250
250
200
200
150
150
100
100
50
50
(a) Daily averages
Average VOC concentration ( g/m3)
(b) Daily peaks
Peak VOC concentration ( g/m3)
3rd Flr Core
3rd Flr South
2nd Flr West
1st Flr Core
1st Flr South
3rd Flr Core
3rd Flr South
2nd Flr West
1st Flr Core
1st Flr South
3rd Flr West
2nd Flr Core
2nd Flr South
1st Flr West
3rd Flr West
2nd Flr Core
2nd Flr South
1st Flr West
42
Figure 28 Frequency distribution of simulated VOC concentration for Medium Office
350
350
0
400
400
50
450
450
100
500
500
150
550
550
200
600
600
250
650
650
300
700
700
350
750
750
400
900
900
# of Days
# of Days
800
800
950
950
850
850
1000
1000
0
50
100
150
200
250
300
350
400
(a) Daily averages
Average VOC concentration ( g/m3)
450
400
400
350
350
300
300
250
250
200
200
150
150
100
100
50
50
Library/Media
Cafeteria
Gym
Offices
Corner Class 1 Pod 1
Library/Media
Cafeteria
Gym
Offices
Corner Class 1 Pod 1
Mult Class 1 Pod1
43
Figure 29 Frequency distribution of simulated VOC concentration for Primary School
(b) Daily peaks
Peak VOC concentration ( g/m3)
450
0
500
500
50
550
550
100
600
600
150
650
650
200
700
700
250
750
750
300
800
800
Mult Class 1 Pod1
850
850
350
900
900
# of Days
# of Days
950
950
400
1000
1000
0
50
100
150
200
250
300
350
400
(a) Daily averages
Average VOC concentration ( g/m3)
450
400
400
350
350
300
300
250
250
200
200
150
150
100
100
50
50
Meeting Room
Guest 309-312
Guest 215-218
Guest 415-418
Guest 209-212
Guest 409-412
Guest 315-318
Meeting Room
Guest 309-312
Guest 215-218
Guest 415-418
Front Lounge
Guest 209-212
Guest 409-412
Guest 315-318
44
Figure 30 Frequency distribution of simulated VOC concentration for Small Hotel
(b) Daily peaks
Peak VOC concentration ( g/m3)
450
0
500
500
50
550
550
100
600
600
150
650
650
200
700
700
250
750
750
Front Lounge
800
800
# of Days
300
850
850
350
900
900
400
950
950
# of Days
1000
1000
0
50
100
150
200
250
300
350
400
450
(a) Daily averages
Average VOC concentration ( g/m3)
500
450
400
400
350
350
300
300
250
250
200
200
150
150
100
100
50
50
Back Space
Core Retail
Front Retail
Point of Sale
Back Space
Core Retail
Front Retail
Point of Sale
45
Figure 31 Frequency distribution of simulated VOC concentration for Stand-Alone Retail
(b) Daily peaks
Peak VOC concentration ( g/m3)
500
0
550
550
50
600
600
100
650
650
150
700
700
200
750
750
250
800
800
300
850
850
350
900
900
400
950
950
# of Days
# of Days
1000
1000
# of Days
0
50
100
150
200
250
0
50
100
150
200
250
0
0
5
5
10
10
15
15
20
20
25
25
30
30
40
45
50
55
40
45
50
60
55
60
g/m3)
(b) PM 2.5
Average PM 2.5 concentration ( g/m3)
35
(a) Ozone
Average ozone concentration (
35
65
65
70
70
75
75
80
80
85
85
95
90
95
Outdoor
Kitchen
Dining
90
Outdoor
Kitchen
Dining
46
Figure 32 Frequency distributions of simulated ozone and PM2.5 daily average concentrations for Full Service Restaurant
# of Days
# of Days
# of Days
0
0
5
5
10
10
15
15
20
20
25
25
30
30
35
35
45
50
55
60
45
50
55
60
(b) PM 2.5
80
65
75
85
90
95
5th Flr Office 2
5th Flr Dining Room
70
3rd Flr Patient Room 4
3rd Flr Nurse Stn. Lobby
Outdoors
3rd Flr Lab
3rd Flr Patient Room 3
2nd Flr ICU
95
2nd Flr OR 2
80
90
1st Flr ER Exam 3
85
2nd Flr ICU Patient Room 3
75
1st Flr ER Nurse Stn.
1st Flr Lobby
Average PM 2.5 concentration ( g/m3)
40
(a) Ozone
65
70
5th Flr Office 2
5th Flr Dining Room
Average ozone concentration ( g/m3)
40
3rd Flr Patient Room 4
3rd Flr Nurse Stn. Lobby
Outdoors
3rd Flr Lab
2nd Flr ICU
2nd Flr OR 2
3rd Flr Patient Room 3
2nd Flr ICU Patient Room 3
1st Flr ER Nurse Stn.
1st Flr ER Exam 3
47
Figure 33 Frequency distributions of simulated ozone and PM2.5 daily average concentrations for Hospital
0
50
100
150
200
250
0
50
100
150
200
250
1st Flr Lobby
# of Days
# of Days
0
0
5
5
10
10
15
15
20
20
25
25
30
30
35
35
45
50
55
60
65
45
50
55
60
65
(b) PM 2.5
Average PM 2.5 concentration ( g/m3)
40
(a) Ozone
Average ozone concentration ( g/m3)
40
70
70
90
95
Outdoors
3rd Flr Core
85
3rd Flr West
3rd Flr South
80
2nd Flr Core
2nd Flr West
75
2nd Flr South
1st Flr West
95
1st Flr Core
1st Flr South
90
Outdoors
3rd Flr Core
85
3rd Flr West
3rd Flr South
80
2nd Flr Core
75
2nd Flr South
2nd Flr West
1st Flr West
1st Flr Core
1st Flr South
48
Figure 34 Frequency distributions of simulated ozone and PM2.5 daily average concentrations for Medium Office
0
50
100
150
200
250
0
50
100
150
200
250
# of Days
0
50
100
150
200
250
0
50
100
150
200
250
0
0
5
5
10
10
15
15
20
20
25
25
30
30
35
35
45
50
55
60
45
50
55
60
65
65
(b) PM 2.5
Average PM 2.5 concentration ( g/m3)
40
(a) Ozone
Average ozone concentration ( g/m3)
40
70
70
75
75
85
90
80
85
Outdoors
Library/Media
Cafeteria
Gym
Offices
90
Corner Class 1 Pod 1
Mult Class 1 Pod1
80
Outdoors
Library/Media
Cafeteria
Gym
Offices
Corner Class 1 Pod 1
Mult Class 1 Pod1
95
95
49
Figure 35 Frequency distributions of simulated ozone and PM2.5 daily average concentrations for Primary School
# of Days
# of Days
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50
Figure 36 Frequency distributions of simulated ozone and PM2.5 daily average concentrations for Small Hotel
0
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35
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Back Space
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51
Figure 37 Frequency distributions of simulated ozone and PM2.5 daily average concentrations for Stand-Alone Retail
# of Days
6. DISCUSSION
The development of the CONTAM models of the reference buildings and their application to
airflow and contaminant transport analyses described in this report will support future studies of
ventilation and IAQ. However, their development presented a number of challenges and other
issues that merit discussion and will hopefully be addressed by additional studies in the future.
6.1. Building models for airflow and energy analyses
While the development of CONTAM models of the DOE reference buildings furthers the ability
to conduct simultaneous energy, airflow and contaminant transport simulations, it also reveals a
number of challenges in doing so. One key issue is that building models developed for
performing airflow and IAQ analyses employ different building representations and require
different data than those used for energy analyses. CONTAM, and other multizone airflow and
indoor air quality (IAQ) models, consider buildings as networks of interconnected zones.
Airflow rates are then calculated based on physical relationships between flow and pressure
analogous to the relationship between heat transfer and temperature differences in energy models.
Thus, it is important that multizone building airflow models capture the geometry of the whole
building, its weather exposure, interzone leakages, and ventilation system airflows. In contrast,
building models for energy analysis are focused on accounting for thermal loads of different
building zones, system efficiencies in meeting these loads, and selecting equipment types and
sizes. As discussed below, the zones used in energy calculations are therefore based on the
similarity and differences between their thermal loads, while the zones used in airflow modeling
are based on pressure relationships and differences in ventilation airflows.
For example, zones with small or insignificant thermal loads, such as stairwells, elevator shafts,
and restrooms, are often not included in energy models. However, stairwells and elevators shafts
need to be included in multizone models because they have a major effect on building pressure
relationships and constitute important airflow paths between zones, particularly in taller
buildings. In addition, zones, even floors, with similar thermal loads are often “multiplied” in
energy models to simplify model inputs. Such spaces are input once and the resulting loads are
multiplied without modeling the individual interior spaces. In multizone models, however, each
zone and floor must be modeled separately to account for horizontal air movement and
contaminant transport and for the effects of elevation on airflow and contaminant transport.
In addition to different approaches to building zoning, another key difference between airflow
and energy models is how they manage airflow balances and interzone airflow. EnergyPlus
generally maintains a balance between the ventilation flows into (supply) and out of (return and
exhaust) each zone. Interzone airflows are sometimes input, but a net airflow balance between
entering and leaving air is maintained for each zone. Infiltration airflows are not part of this
balance but are considered only as they impact the thermal loads of the zone. In contrast,
CONTAM and other multizone airflow models use the mass balance of air for each zone to
determine the amount of infiltration and exfiltration for each zone to the outdoors and/or adjacent
zones. Therefore, the system flows are an input while temperature differences and wind
pressures serve as boundary conditions, which in conjunction with leakage values of the zone
boundaries are used determine these infiltration and exfiltration flows.
52
For example, equal airflows are specified between dining and kitchen zones in the EnergyPlus
models of the restaurants. The value of this interzone airflow is based on minimum ventilation
requirements for these zones, but does not reflect the actual physics driving the airflow. In
contrast, CONTAM and other airflow models actually calculate this airflow based on the
interzone pressure difference across the openings between the zones.
Another difference is the manner in which energy and airflow models manage the common
practice in commercial building design of maintaining an excess of supply over return airflow to
reduce envelope infiltration. As noted above, energy models maintain a net balance between
incoming and outgoing ventilation airflows, so an excess of supply air is not reflected in these
models. Airflow models on the other hand need to consider these ventilation airflow differences,
as they are key in determining building pressure relationships. It’s worth noting that while the
EnergyPlus models included kitchens with their excess exhaust flow, that flow did not impact the
building airflow dynamics. CONTAM, on the other hand, included both kitchen and restroom
exhausts and calculated their impacts on building pressures and airflows. Spaces with local
exhaust flows must also be included as separate zones to properly account for their effects on
building pressures.
The most important differences in how multizone and energy building models handle infiltration
is evident in the differences between the building infiltration rates reported in Section 4. The
infiltration rates in the EnergyPlus models are input assuming that the indoor-outdoor pressure
differences are always negative 4 Pa, i.e., air enters the buildings at all points on the exterior
envelope. The airflow results reported in Section 4 demonstrate that the constant infiltration rates
assumed in EnergyPlus do not reflect the physical dependence of infiltration on weather
conditions. The largest discrepancies occur for larger differences between indoor and outdoor
temperatures and for higher wind speeds, resulting in substantial under-prediction of the
infiltration rates and the resultant energy impact for the EnergyPlus (tight) models. The
infiltration rates and sensible loads calculated using CONTAM were as much as six to nine times
greater than the EnergyPlus (tight) results but only 30 % to two times greater than the
EnergyPlus (CONTAM-equiv.) results. Thus, the selection of an infiltration or envelope leakage
rate to be used in building energy simulation needs to be carefully considered since it can
significantly impact the predicted airflow and energy use. However, given the very limited data
on building envelope leakage, selecting these values is a significant challenge for both energy
analysis and airflow simulation. Nevertheless, assuming constant infiltration airflow rates in
energy simulation, no matter the value, cannot capture the important effects of weather on
infiltration. Thus, a more accurate treatment of infiltration should be applied to EnergyPlus
models and building energy simulation in general. As an alternative to performing multizone
analysis using tools like CONTAM, simple empirical relationships between infiltration rates,
airtightness, system operation and weather can be developed for use in energy simulation. The
challenge is to develop such algorithms that can provide sufficiently accurate infiltration rates for
various building sizes, designs and shapes and under various weather conditions.
53
6.2. Limitations of study
The CONTAM models of the reference buildings provide important tools to evaluate the
ventilation and IAQ performance of various building and system design options in conjunction
with EnergyPlus analyses. However, there are a number of limitations to the CONTAM models
that need to be considered and potentially addressed in the future. As discussed in Section 3.1, to
simplify CONTAM modeling, the maximum supply airflow rates calculated by EnergyPlus were
used in the CONTAM models. Therefore, variable-air volume (VAV) system effects were not
included. Also, the CONTAM simulations maintained a constant indoor temperature and used
the minimum amount of outdoor ventilation air specified in EnergyPlus for each zone (or HVAC
system) with no economizer cycle. Thus, future applications of CONTAM to these models may
consider varying supply airflow rates, varying indoor temperatures, and economizer operation.
It is also important to note that coupled airflow-thermal interaction cannot be fully be captured
by performing independent airflow and thermal simulations, which is especially important for
modeling natural or hybrid ventilation approaches. Current methods of coupling airflow-thermal
simulations include ping-pong, onion, or fully-integrated (Ng and Persily 2011). Ping-pong
coupling passes airflow and temperature values between two separate simulations at each time
step. Onion coupling passes airflow and temperature values between two separate simulations
within each time step until convergence is reached. Lastly, fully-integrated coupling
simultaneously solves the airflow and energy equations within a single simulation.
Fully-integrated coupling is the most computationally intensive of the three coupling methods,
but may more accurately capture the airflow-thermal interactions. The most appropriate coupling
method depends in part to the degree with which the airflow-thermal problem is coupled. The
more highly coupled the interaction, such as in naturally ventilated buildings where large
temperature gradients may exist and are important drivers of airflow, the more sophisticated the
coupling method will need to be. Other important factors in selecting an appropriate airflowthermal coupling method include: achievable convergence of airflow and thermal values, and the
differences in time scales between the airflow (on the order of minutes or hours) and thermal (on
the order of seconds to hours) problem. Wang et al. (2010) developed a fully-integrated coupling
method and compared its performance to an onion-coupled simulation for a buoyancy-driven
problem. The study found numerical instabilities with the onion-coupled method. The
fully-integrated coupling method was not subject to these instabilities and predicted airflow rates
and temperatures comparable to the results of a CFD simulation with significantly reduced
computational cost. Nevertheless, more development and testing of coupling techniques for a
variety of airflow-thermal problems are still needed.
6.3. Presenting IAQ simulation results
In using multizone models for IAQ analysis to conduct IAQ simulations to evaluate different
buildings and design approaches, the manner in which to present the simulation results is
somewhat challenging. IAQ simulations conducted over a year, or any significant period of time,
in a multizone building produces a large amount of data. Running such simulations for different
conditions of building operation, source strengths, weather conditions or other parameters
quickly multiplies the amount of data produced. Converting these data into understandable
formats and drawing useful conclusions is difficult, and there are no standard approaches for
doing do.
54
One challenging aspect of analyzing IAQ simulation results is the comparison of the predicted
concentrations to meaningful reference values, given the lack of such reference or limit values
for most indoor contaminants. As discussed in Section 5, two of the simulated contaminant
concentrations (ozone and PM 2.5) were compared with the NAAQS outdoor air limits and
WHO indoor air guidelines. However, the other contaminants simulated, CO2 and VOCs, do not
have guidelines for comparison, let alone formalized, health-based limits. The same lack of
concentration limits is also the case for many other indoor air contaminants. As noted in Persily
and Emmerich (2012), the diversity of occupants and contaminants and the lack of guidelines for
exposure limits to the numerous contaminants present in buildings means that IAQ cannot not be
judged as good or bad in terms of contaminant concentration(s) alone. Unlike energy
consumption or thermal comfort, which can be quantified in terms well-defined parameters, the
complex interaction of ventilation rates, contaminant sources, interaction and removal
mechanisms, and occupant behavior make the evaluation of IAQ extremely challenging.
The need for IAQ metrics has been considered previously but no set of metrics has been accepted.
TenBrinke et al. (1998) correlated results of occupant surveys with total VOC levels. Hollick and
Sangiovanni (2000) developed a metric that accounted for the effects of human health and
comfort on individuals by various contaminants. Sofuoglo and Moschandreas (2003) aggregated
the concentrations of eight contaminants and correlated the resulting metric with occupant
surveys to determine an Indoor Air Pollution Index (IAPI). Jackson et al. (2011) based their
assessment of IAQ on the potential health risk of VOC exposure to occupants. Catalina and
Iordache (2012) proposed an index that incorporated energy consumption, visual comfort,
acoustics, and air change rate, but did not consider contaminant concentrations. It is not yet
possible to say which IAQ metric is most useful based on their limited application and
fundamentally because each situation is different. Thus, the development of an IAQ metric, or
perhaps multiple metrics, that is widely applicable to a range of buildings is still a major need.
6.4. Future work
The EnergyPlus and CONTAM models of the reference buildings serve as baseline cases, which
can be used in future analyses to support the design and implementation of strategies to
simultaneously reduce building energy use while maintaining or improving IAQ, such as
alternative ventilation approaches, enhanced filtration and contaminant source control. Among
these ventilation approaches, heat recovery ventilation can maintain outdoor air ventilation rates
while providing “free” heat exchange between warmer air returned to the system and colder air
entering from outdoors in the winter. Demand control ventilation can reduce outdoor air
ventilation rates during periods of low occupancy, thus reducing the energy required to condition
outdoor air. Economizer operation can increase outdoor air ventilation while also reducing the
amount of mechanical cooling when weather conditions and outdoor air quality are suitable.
Source control and enhanced filtration also have the potential to improve IAQ while potentially
reducing energy use if ventilation rates can be decreased. Natural and hybrid (or mixed mode)
ventilation also has the potential to simultaneously reduce energy consumption and improve IAQ,
however the analysis of these and other approaches can be limited by the inability of current
simulation tools to model building airflow and contaminants in a physically reasonable fashion.
Given that this study considered a limited set of contaminants, future work should include
additional contaminants, including those that are unique to specific building types. For example,
55
particles from cooking in the Full Service Restaurant and infectious biological agents in the
Hospital both merit attention. There are also numerous other contaminants that are known to
affect occupant health and comfort, such as carbon monoxide, formaldehyde and individual
VOCs (WHO 2005; WHO 2010) that were not simulated in this study. In addition, other
simulations may benefit from considering other transport mechanisms, such as particle
deposition, absorption/desorption of VOCs, and enhanced filtration.
7. CONCLUSION
The reference buildings created by DOE in EnergyPlus are intended for assessing new
technologies and developing energy codes. However, infiltration rates were assumed in the
models (not calculated), which may have a substantial impact on predicted energy impacts of
some of these technologies. Also, the limited ability of EnergyPlus to model contaminant
transport greatly limits the ability to assess the impact of these technologies on IAQ. Based on
these limitations, CONTAM models of the 16 reference buildings were created in order to
perform airflow and IAQ analyses. Six of the reference buildings, representing each type of
occupancy covered by the 15 commercial reference buildings (excluding the Midrise Apartment
building), were selected for annual airflow and contaminant simulations.
While the total building outdoor air change rates were similar for the EnergyPlus and CONTAM
models, the infiltration rates calculated by CONTAM were two to six times greater than the
assumed inputs in the EnergyPlus (tight) models. The infiltration rates calculated with the
EnergyPlus (CONTAM-equiv.) models were closer to the CONTAM predictions. More
importantly however, the assumed infiltration rates in EnergyPlus did not reflect the impacts of
outdoor weather conditions, which were captured by CONTAM. This inability of the EnergyPlus
models to account for weather resulted in substantial under-prediction of the energy impact of
infiltration rates and associated energy impacts during colder and windier weather conditions.
In all of the selected buildings and zones, the simulated indoor contaminant levels did not exceed
limits set by relevant standards and guidelines for most hours of the year. Note that the IAQ
simulations in this study only used a limited set of contaminants and relatively constant source
strengths. Additional simulations of other contaminants and source strengths, as well as IAQ
control technologies, are needed to better understand a range of important IAQ issues.
The EnergyPlus and CONTAM models of the reference buildings serve as baseline cases, which
will be useful in future analyses to support the design and implementation of alternative
ventilation and IAQ control approaches that can simultaneously reduce building energy use
while maintaining if not improving IAQ.
56
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Appendix A Detailed description of CONTAM models of reference buildings
A1. INTRODUCTION
This appendix summarizes the development of multizone network airflow models for the
16 reference buildings developed by the DOE (Deru et al. 2011). The purpose of this appendix is
to document the modeling assumptions, decisions, and structure. The models are intended for use
in investigating a variety of indoor air quality issues, which will require a working knowledge of
how the models were developed.
Multizone Modeling: Background information
Multizone network airflow modeling is a method for calculating building pressures, airflows and
contaminant transport. Buildings are represented by a network of “zones” connected by
“airflow paths”. Zones are discrete volumes of air within which mass is conserved, and that
generally have uniform temperature, pressure, and contaminant concentration. Air moves
between zones along airflow paths with defined flow rates or pressure-dependent resistance to
airflow. Contaminants move through the building with the bulk airflow, and can be generated or
removed, and may undergo chemical reactions in CONTAM. The CONTAM software and more
information specific to it can be found at http://www.bfrl.nist.gov/IAQanalysis.
Building input specifications
Zoning strategy: The predominant zoning strategy used in the models is one zone per physical
room. The zoning generally matches that used in the EnergyPlus models. In some cases, similar
rooms are grouped together into a single zone in EnergyPlus in order to simplify thermal
calculations. “Multipliers” are used in the EnergyPlus models to indicate that the thermal load
for one particular zone is to be applied to several other ones, or simply multiplied. Each zone is
served by the same system and has the same occupancy and usage profiles in EnergyPlus. In
CONTAM, each zone is also experiences the same wind and stack effects. Examples of zones
with multipliers in the EnergyPlus models are classrooms in the schools, guest rooms in the
hotels, and examination rooms in the hospital. How these multiplied zones are modeled in
CONTAM will be discussed in Section A2.
The three office models are also zoned to match the EnergyPlus models. In each office, each
floor consists of five zones – four perimeter and one core zone. This layout is often used in
thermal models of buildings with open-office plans. In EnergyPlus, these zones are separated by
solid walls, thereby creating temperature differences between the zones. There is no air exchange
between the zones in EnergyPlus. In contrast, large openings are modeled between the zones in
CONTAM so that air exchange can occur.
In some buildings, zones are added or subdivided to make the models more realistic and useful
as multizone models. These changes are noted on the drawings of the individual buildings in
Section A2. The changes mostly involve the addition of restrooms, stairwells, and elevator shafts.
These are zones whose unique features can significantly influence building airflow, and are thus
desirable to include in a multizone network airflow model of a building.
61
Holiday schedules: Many of the buildings use holidays in their occupancy schedules. For all of
the buildings, holidays fall on the following days:
January 1
November 11
December 25
July 4
3rd Monday in January
3rd Monday in February
Last Monday in May
1st Monday in September
2nd Monday in October
4th Thursday in November
The two schools also have different schedules for summer weekdays. Summer is defined as the
days from July 1 to end of the day on August 31. Summer weekdays are modeled using a
“type 12” day in CONTAM. The CONTAM weather file used with the schools uses the “type 12”
day type for all summer weekdays except holidays.
Daylight savings
Daylight savings is implemented from the 2nd Sunday in March to the end of the day on the
1st Sunday in November.
Weather
Steady-state weather is defined in the base models with an outdoor temperature of 20 ºC and no
wind. The ambient pressure is 1 atm. A wind speed modifier of 0.36 was specified for all exterior
leakage paths.
Transient weather: The annual simulations utilized transient weather files. The files were
imported into the CONTAM weather file format (.WTH) from a TMY2 weather file for Chicago
O-Hare (DOE 2011). Two CONTAM weather files were created – one for the schools, one for
the remaining buildings. In both files, the calendar for weekends, holidays, and daylight savings
time was set to match the EnergyPlus models:
January 1 is a Sunday
Daylight savings is implemented from the 2nd Sunday in March to the end of the day on
the 1st Sunday in November
No weekend holiday rule is used, meaning holidays that fall on a weekend are not
observed on the following Monday
The first of the two files, Chicago.wth, is intended for use with all of the buildings except the
schools. The second, ChicagoSchools.wth, is identical except that all weekdays between July 1
and August 31 are designated as “type 12” days. A summer weekday HVAC operation is the
same as for the rest of the year. A summer weekday occupancy schedule, however, is different
than for the rest of the year.
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For users who will create CONTAM weather files for other cities, the “type 12” day must be
used for summer weekdays in the schools. Otherwise, the building occupancy in CONTAM will
not match those in the EnergyPlus models on these days.
A2. BUILDINGS DESCRIPTION
This section summarizes the specific geometry, zones, system flow rates and types, occupants,
and schedules used in each of the building models. All flow rates shown are shown for Chicago.
In general, minimum ventilation requirements (or “outside air”) do not vary between cities or
building vintages.
A2.1.
Quick Service Restaurant
Table A1 summarizes the zones modeled in CONTAM for the Quick Service Restaurant, their
respective sizes, and maximum occupancy.
Table A1 Summary of zones in Quick Service Restaurant
Zone
Area (m2)
Height (m)
Dining
Kitchen
Restroom
Attic
116
100
16
232
3.05
3.05
3.05
1.13
Maximum
occupancy
83.33
6.25
0
0
Geometry:
232.2 m2 footprint, single-story building with attic. The EnergyPlus model has two zones (not
including the Attic) – Dining and Kitchen. In the CONTAM model, a Restroom (shaded in
Figure A1) with a footprint of 4 m 4 m was carved out of the Kitchen.
4m
Kitchen
4m
Restroom
7.62 m
Dining
7.62 m
15.23 m
Figure A1 Floor plan of Quick Service Restaurant (height 3.05 m)
The building models for the New and Post-1980 buildings have an attic roof. The Pre-1980
building has a flat roof and no attic zone.
63
Large interior leakage paths were defined as follows:
Between the Dining and Kitchen zones, a single large leakage path of 25.7 m2 (75 % of the
total wall area between the two spaces) is modeled;
Between the Restroom and Dining zones, a 0.186 m2 transfer grille is modeled.
HVAC systems:
For all building vintages, the EnergyPlus model has two packaged constant-volume single-zone
systems. In CONTAM, the Dining zone has a constant-volume system. However, the Kitchen is
supplied 100 % outside air using a dedicated fan. The supply air, return air, outside air, and
exhaust flow rates modeled in CONTAM are listed in Table A2 for all building vintages. The
exhaust flow rate for the Restroom was modeled only in CONTAM, not in EnergyPlus.
The EnergyPlus model has a Dining exhaust fan (0.83 m3/s) in addition to the Kitchen exhaust
fan (0.72 m3/s). It was included in order to transfer air from the Dining zone to the Kitchen. This
is modeled in CONTAM using a large opening between the Dining and Kitchen zones
(see above), and one exhaust fan in the Kitchen (1.52 m3/s) and one in the Restroom (0.04 m3/s).
In EnergyPlus, neutral building pressurization is modeled in all zones. Based on discussion with
restaurant designers, it is most realistic to model the restaurant with a balanced system in
CONTAM as well.
Table A2 Summary of HVAC system flow rates (m3/s) in Quick Service Restaurant
Zone
Dining
Kitchen
Restroom
New
Supply
Return
Post-1980
Supply Return
Pre-1980
Supply Return
1.20
N/A
N/A
0.37
N/A
N/A
1.20
N/A
N/A
1.51
N/A
N/A
0.37
N/A
N/A
0.68
N/A
N/A
Outside
air
(m3/s)
0.83
0.05
0
Exhaust
air
(m3/s)
0
1.52
0.04
Schedules:
All HVAC and exhaust fans operate on the following schedule:
Every day: on from 5:00 a.m. to 1:00 a.m., off otherwise
Outside air is supplied according to this schedule as well.
Occupants:
The peak number of people for each zone is listed in Table A1. Occupants in all building zones
are scheduled according to Figure A2 . There is a different occupancy schedule for weekdays and
weekends/holidays.
64
Occupancy Schedules
1
Weekday
0.9
Weekend, Holiday
0.8
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A2 Occupancy schedule for Quick Service Restaurant
A2.2.
Full Service Restaurant
Table A3 summarizes the zones modeled in CONTAM for the Full Service Restaurant, their
respective sizes, and maximum occupancy.
Table A3 Summary of zones in Full Service Restaurant
Zone
Area (m2)
Height (m)
Dining
Kitchen
Restroom
Attic
372
139
16
511
3.05
3.05
3.05
1.68
Maximum
occupancy
266.77
7.5
0
0
Geometry:
511 m2 footprint, single-story building with attic. The EnergyPlus model has two zones (not
including the Attic) – Dining and Kitchen. In the CONTAM model, a Restroom (shaded in
Figure A3) with a footprint of 4 m 4 m was carved out of the Kitchen.
The building models for new and post-1980 buildings have an attic roof. The Pre-1980 building
has a flat roof and no attic zone.
Large interior leakage paths were defined as follows:
Between the Dining and Kitchen zones, a single large leakage path of 42.57 m2 (75 % of
the total wall area between the two spaces) is modeled;
Between the Restroom and Dining zones, a 0.186 m2 transfer grille is modeled.
65
4m
Kitchen
Restroom
4m
6.17 m
Dining
16.44 m
22.61 m
Figure A3 Floor plan of Full Service Restaurant (height 3.05 m)
HVAC systems:
For all building vintages, the EnergyPlus model has two packaged constant-volume single-zone
systems. In CONTAM, the Dining zone has a constant-volume system. However, the Kitchen is
supplied 100 % outside air using a dedicated fan. The supply air, return air, outside air, and
exhaust flow rates modeled in CONTAM are listed in Table A4 for all building vintages. The
exhaust flow rate for the Restroom was modeled only in CONTAM, not in EnergyPlus.
The EnergyPlus model has a Dining exhaust fan (1.83 m3/s) in addition to the Kitchen exhaust
fan (0.06 m3/s). It was included in order to transfer air from the Dining zone to the Kitchen. This
is modeled in CONTAM using a large opening between the Dining and Kitchen zones (see
above), and one exhaust fan in the Kitchen (1.85 m3/s) and one in the Restroom (0.04 m3/s).
In EnergyPlus, neutral building pressurization is modeled in all zones. Based on discussion with
restaurant designers, it is most realistic to model the restaurant with a balanced system in
CONTAM as well.
Schedules:
All HVAC and exhaust fans operate on the following schedule:
Every day: on from 5:00 a.m. to 1:00 a.m., off otherwise
Outside air is supplied according to this schedule as well.
Table A4 Summary of HVAC system flow rates (m3/s) in Full Service Restaurant
Zone
Dining
Kitchen
Restroom
New
Supply
Return
Post-1980
Supply Return
Pre-1980
Supply Return
2.88
N/A
N/A
1.72
N/A
N/A
3.13
N/A
N/A
3.64
N/A
N/A
1.97
N/A
N/A
66
2.48
N/A
N/A
Outside
Air
(m3/s)
2.67
0.06
0
Exhaust
air
(m3/s)
0
1.85
0.04
Occupants:
The peak number of people for each zone is listed in Table A3. Occupants in all building zones
are scheduled according to Figure A4. There is a different occupancy schedule for weekdays,
Saturdays, and Sundays/holidays.
Occupancy Schedules
1
Weekday
0.9
Saturday
0.8
Sunday, Holiday
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A4 Occupancy schedule for Full Service Restaurant
A2.3.
Small Office
Table A5 summarizes the zones modeled in CONTAM for the Small Office, their respective
sizes, and maximum occupancy.
Geometry:
511 m2 footprint, single-story building with attic. The EnergyPlus model has five zones – four
perimeter zones and a core zone. In the CONTAM model, a Restroom (shaded in Figure A5 )
with a footprint of 4 m 4 m was carved out of the Core zone.
The building models for new and post-1980 buildings have a vented attic. The Pre-1980 building
has insulation above the roof deck, with no attic zone.
Large interior leakage paths were defined as follows:
Between the perimeter and core zones, a single large leakage path (50 % of the total wall
area between the two spaces) is modeled. This is representative of half-height office
partitions;
Between the Restroom and Core zones, a 0.186 m2 transfer grille is modeled.
67
Table A5 Summary of zones in Small Office
Zone
Area (m2)
Height (m)
Core
Perimeter South
Perimeter East
Perimeter North
Perimeter West
Attic
Restroom
133.66
113.45
67.30
113.45
67.30
511
16.0
3.05
3.05
3.05
3.05
3.05
1.64
3.05
Maximum
occupancy
8.05
6.11
3.62
6.11
3.62
0
0
27.69 m
Perimeter North
18.46 m
5m
4m
Perimeter
West
Core
Restroom
4m
Perimeter
East
Perimeter South
5m
17.69 m
8.46 m
5m
5m
Figure A5 Floor plan of Small Office (height 3.05 m)
HVAC systems:
For all building vintages, the EnergyPlus model has five packaged constant-volume single-zone
systems. Similarly, each zone has a constant-volume system in CONTAM. The supply air, return
air, outside air, and exhaust flow rates modeled in CONTAM are listed in Table A6 for all
building vintages. The exhaust flow rate for the Restroom was modeled only in CONTAM, not
in EnergyPlus.
In EnergyPlus, neutral building pressurization is modeled in all zones. To pressurize the building
in CONTAM, less air is returned than is supplied to each zone. The return airflow rate is the
larger of (a) 90 % of the supply airflow rate and (b) supply airflow rate minus outside air
requirement. Return air from the Core zone is reduced by the amount of Restroom exhaust air.
The building is neutrally pressurized between 6:00 a.m. and 7:00 a.m. on weekdays and
Saturdays when the system operates but no outside air is being supplied.
68
Table A6 Summary of HVAC system flow rates (m3/s) in Small Office
Zone
Core
Perimeter South
Perimeter East
Perimeter North
Perimeter West
Restroom
New
Supply
Return
Post-1980
Supply Return
Pre-1980
Supply Return
0.45
0.36
0.33
0.36
0.36
N/A
0.37
0.32
0.30
0.32
0.32
N/A
0.55
0.52
0.37
0.51
0.44
N/A
0.58
0.97
0.61
0.96
0.64
N/A
0.47
0.47
0.33
0.46
0.40
N/A
0.50
0.91
0.57
0.90
0.60
N/A
Outside
Air
(m3/s)
0.08
0.06
0.04
0.06
0.04
0
Exhaust
air
(m3/s)
0
0
0
0
0
0.05
Schedules:
All HVAC and exhaust fans operate on the following schedule:
Weekdays: on from 6:00 a.m. to 10:00 p.m., off otherwise
Saturday: on from 6:00 a.m. to 6:00 p.m., off otherwise
Sunday, holidays: off all day
The outside air for the HVAC systems operate on the following schedule:
Weekdays: on from 7:00 a.m. to 10:00 p.m., off otherwise
Saturday: on from 7:00 a.m. to 6:00 p.m., off otherwise
Sunday, holidays: off all day
Occupants:
The peak number of people for each zone is listed in Table A5. Occupants in all building zones
are scheduled according to Figure A6. There is a different occupancy schedule for weekdays and
Saturdays. Sundays and holidays are unoccupied.
Occupancy Schedules
1
Weekday
0.9
Saturday
0.8
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A6 Occupancy schedule for Small Office
69
A2.4.
Medium Office
Table A7 summarizes the zones modeled in CONTAM for the Medium Office, their respective
sizes, and maximum occupancy.
Table A7 Summary of zones in Medium Office
Zone
Floor
Area (m2)
Height (m)
Core
Perimeter South
Perimeter East
Perimeter North
Perimeter West
Restroom
Stairwell
Elevator shaft
Plenum
Stair at Plenum
Elev. at Plenum
1-3
1-3
1-3
1-3
1-3
1-3
1-3
1-3
Abv 1-3
Abv 1-3
Abv 1-3
823
207
131
207
131
100
30
30
1600
30
30
2.74
2.74
2.74
2.74
2.74
2.74
2.74
2.74
1.26
1.26
1.26
Maximum
occupancy
52.93
11.16
7.06
11.16
7.06
0
0
0
0
0
0
Geometry:
1661 m2 footprint, three-story building with flat roof. Total floor area is 4982 m2. The
EnergyPlus model has five zones per occupied floor – four perimeter zones and a core zone.
Floor to ceiling height is 2.74 m and floor to floor height is 4.0 m. The additional height is due to
plenums above each floor. Every floor (excluding the plenums) has the same floor plan. All of
the plenums have the same floor plans. In the CONTAM model, a Restroom (shaded in
Figure A7) with a footprint of 10 m 10 m was carved out of the Core zone. Also carved out of
the Core zone are a 3 m 10 m Stairwell and a 3 m 10 m Elevator Shaft (shaded in Figure A7).
49.911 m
Perimeter North
4.573 m
3 m 10 m 3m
33.274 m
Perimeter
West
Core
10 m
St
air
Restroom
El
ev
Perimeter
East
4.573 m
Perimeter South
4.573 m
40.765 m
4.573 m
Figure A7 Floor plan of Medium Office (height 2.74 m)
70
24.128 m
Large interior leakage paths were defined as follows:
Between the perimeter and core zones, a single large leakage path (50 % of the total wall
area between the two spaces) is modeled. This is representative of half-height office
partitions;
Between the Restroom and Core zones, a 0.186 m2 transfer grille is modeled;
A leakage path between each occupied zone and the plenum above, equal to 1 % of the
floor area of the occupied zone, is modeled to accommodate transfer of return air to the
HVAC system through the plenum;
A stairwell is defined using CONTAM’s stair shaft model for closed treads and zero
people;
An elevator shaft is defined using CONTAM’s elevator shaft model.
HVAC systems:
For the New and Post-1980 buildings, the EnergyPlus model has three variable air volume (VAV)
systems, each serving one floor. The design supply flow rate calculated by EnergyPlus for each
VAV system is used as the supply flow rate for each constant-volume system modeled in
CONTAM for simplicity. The systems modeled in CONTAM are still referred to as “VAV”
systems in the body of this text. Varying the supply flow rate can be implemented in CONTAM
using controls and/or schedules by users who wish to do so. The supply air, return air, outside air,
and exhaust flow rates modeled in CONTAM are listed in Table A8 for the New and Post-1980
buildings. The exhaust flow rates for the Restrooms were modeled only in CONTAM, not in
EnergyPlus.
For the New and Post-1980 buildings, the return path for each VAV system in EnergyPlus
travels through a plenum above the floor it serves. This is modeled in CONTAM with a large
return located in each plenum and a passive opening between the zone and the plenum above that
is sized to obtain a maximum velocity of 2 m/s at the grille opening (grille sizes listed in
Table A8).
For the Pre-1980 buildings, the EnergyPlus model has 15 constant air volume (CAV) systems,
each serving one zone. Similarly, each zone has a constant-volume system in CONTAM. The
supply air, return air, outside air, and exhaust flow rates modeled in CONTAM are listed in
Table A9 for the Pre-1980 buildings.
In EnergyPlus, neutral building pressurization is modeled in all zones. To pressurize the building
in CONTAM, less air is returned than is supplied to each zone. For the New and Post-1980
buildings, the total return plus Restroom exhaust flow rate for each system is set to 90 % of the
total supply airflow rate. For the Pre-1980 buildings, the return airflow rate is the larger of (a) 90
% of the supply airflow rate and (b) supply airflow rate minus outside air requirement. Return air
from the Core zone is reduced by the amount of Restroom exhaust air. Although the plenums
exist in the models of the Pre-1980 building, they are not used as a pathway for airflow, and
there are no return grilles in the ceiling. For all building vintages, the building is neutrally
pressurized between 6:00 a.m. and 7:00 a.m. on weekdays and Saturdays when the system
operates but no outside air is being supplied.
71
Schedules:
All HVAC and exhaust fans operate on the following schedule:
Weekdays: on from 6:00 a.m. to 10:00 p.m., off otherwise
Saturday: on from 6:00 a.m. to 6:00 p.m., off otherwise
Sunday, holidays: off all day
The outside air for the HVAC systems operate on the following schedule:
Weekdays: on from 7:00 a.m. to 10:00 p.m., off otherwise
Saturday: on from 7:00 a.m. to 6:00 p.m., off otherwise
Sunday, holidays: off all day
Occupants:
The peak number of people for each zone is listed in Table A7. Occupants in all building zones
are scheduled according to Figure A8. There is a different occupancy schedule for weekdays and
Saturdays. Sundays and holidays are unoccupied.
72
Table A8 Summary of VAV system flow rates (m3/s) in Medium Office for
New and Post-1980 buildings
Zone
Core
Perimeter South
Perimeter East
Perimeter North
Perimeter West
Restroom
VAV 1 total
Core
Perimeter South
Perimeter East
Perimeter North
Perimeter West
Restroom
VAV 2 total
Core
Perimeter South
Perimeter East
Perimeter North
Perimeter West
Restroom
VAV 3 total
Floor New
Supply
1
1
1
1
1
1
2
2
2
2
2
2
3
3
3
3
3
3
3.21
0.68
0.83
0.57
1.04
N/A
6.32
3.09
0.87
0.96
0.75
1.17
N/A
6.85
3.05
0.94
0.95
0.86
1.25
N/A
7.04
Return
N/A
5.59
N/A
6.06
N/A
6.24
Post-1980
Supply Return
3.51
0.76
0.87
0.66
1.10
N/A
6.90
3.47
0.97
1.02
0.85
1.23
N/A
7.54
3.30
0.99
0.99
0.91
1.28
N/A
7.48
N/A
6.11
N/A
6.69
N/A
6.63
Return
Grille
Size (m2)
1.76
0.38
0.43
0.33
0.55
N/A
1.73
0.49
0.51
0.43
0.62
N/A
1.65
0.50
0.50
0.46
0.64
N/A
Outside
Air
(m3/s)
0.57
0.12
0.15
0.10
0.18
0
1.12
0.51
0.14
0.16
0.12
0.19
0
1.12
0.48
0.15
0.15
0.14
0.20
0
1.12
Exhaust
air
(m3/s)
0
0
0
0
0
0.10
0
0
0
0
0
0.10
0
0
0
0
0
0.10
Table A9 Summary of CAV system flow rates in Medium Office for Pre-1980 building
Zone
Core
Perimeter South
Perimeter East
Perimeter North
Perimeter West
Core
Perimeter South
Perimeter East
Perimeter North
Perimeter West
Core
Perimeter South
Perimeter East
Perimeter North
Perimeter West
Floor
1
1
1
1
1
2
2
2
2
2
3
3
3
3
3
Pre-1980
Supply
Return
3.53
1.05
0.99
1.04
1.25
3.47
1.13
1.14
1.12
1.38
3.61
1.52
1.1
1.52
1.47
3.08
0.95
0.92
0.94
1.18
3.02
1.02
1.07
1.01
1.31
3.15
1.41
1.03
1.41
1.40
73
Outside
Air
(m3/s)
0.66
0.14
0.09
0.14
0.09
0.66
0.14
0.09
0.14
0.09
0.66
0.14
0.09
0.14
0.09
Occupancy Schedules
1
Weekday
0.9
Saturday
0.8
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A8 Occupancy schedule for Medium Office
A2.5.
Large Office
Table A10 summarizes the zones modeled in CONTAM for the Large Office, their respective
sizes, and maximum occupancy.
Geometry:
3563 m2 footprint, 12-story building (plus a basement) with flat roof. Total floor area is
46 320 m2 which includes the Basement. The EnergyPlus model has five zones per occupied
floor – four perimeter zones and a core zone. Floor to ceiling height is 2.74 m and floor to floor
height is 4.0 m. The additional height is due to plenums above each floor. The Basement is a
single zone with the same footprint as the upper floors, with a height of 2.44 m. There is no
plenum between the basement and the first floor. Every floor (excluding the Basement and
plenums) has the same floor plan. All of the plenums have the same floor plans. In the
CONTAM model, a Restroom (shaded in Figure A9) with a footprint of 10 m 10 m was carved
out of the Core zone. Also carved out of the Core zone are a 3 m 10 m Stairwell and a 3 m
10 m Elevator Shaft (shaded in Figure A9).
Large interior leakage paths were defined as follows:
Between the perimeter and core zones, a single large leakage path (50 % of the total wall
area between the two spaces) is modeled. This is representative of half-height office
partitions;
Between the Restroom and Core zones, a 0.186 m2 transfer grille is modeled;
74
A leakage path between each occupied zone and the plenum above, equal to 1 % of the
floor area of the occupied zone, is modeled to accommodate transfer of return air to the
HVAC system through the plenum;
A stairwell is defined using CONTAM’s stair shaft model for closed treads and zero
people;
An elevator shaft is defined using CONTAM’s elevator shaft model.
Table A10 Summary of zones in Large Office
Zone
Floor
Area (m2)
Height (m)
Basement
Perimeter North
Perimeter East
Perimeter South
Perimeter West
Core
Restroom
Stairwell
Elevator shaft
Plenum
Stair at Plenum
Elev. at Plenum
B
1-12
1-12
1-12
1-12
1-12
1-12
1-12
1-12
Abv 1-12
Abv 1-12
Abv 1-12
3563.1
313.4
313.4
202.0
202.0
2372
100
30
30
3563.1
30
30
2.44
2.74
2.74
2.74
2.74
2.74
2.74
2.74
2.74
1.26
1.26
1.26
Maximum
occupancy
95.88
16.87
16.87
10.87
10.87
136.29
0
0
0
0
0
0
73.107 m
Perimeter North
4.573 m
3 m 10 m 3m
48.738 m
Perimeter Core
West
10 m
St
air
Restroom
El
ev
Perimeter
East
Perimeter South
4.573 m
63.961 m
39.592 m
4.573 m
4.573 m
Figure A9 First floor plan of Large Office (height 2.74 m).
Second through twelfth floors are identical to first floor.
75
HVAC systems:
For all building vintages, the EnergyPlus model has four VAV systems. One serves the
Basement, one serves the bottom (1st) floor, one serves the “middle” (2nd through 11th) floors,
and one serves the top (12th) floor. The design supply flow rate calculated by EnergyPlus for
each VAV system is used as the supply flow rate for each constant-volume system modeled in
CONTAM for simplicity. The systems modeled in CONTAM are still referred to as “VAV”
systems in the body of this text. Varying the supply flow rate can be implemented in CONTAM
using controls and/or schedules by users who wish to do so. The HVAC system, outside air, and
exhaust flow rates modeled in CONTAM are listed in Table A11 for building vintages. The
exhaust fans for the Restrooms were modeled only in CONTAM, not in EnergyPlus.
In EnergyPlus, a “middle floor” is multiplied by a factor of 10. Thus, a single VAV system
serving the “middle floor” is actually serving 10 floors. In CONTAM, the middle floor VAV
system is modeled as 10 separate systems.
The Basement has no plenum, so air is returned back to its system. For the remaining VAV
systems, the return path travels through a plenum above that floor. This is modeled in CONTAM
with a large return located in each plenum and a passive opening between the zone and the
plenum above that is sized to obtain a maximum velocity of 2 m/s at the grille opening.
In EnergyPlus, neutral building pressurization is modeled in all zones. To pressurize the building
in CONTAM, less air is returned than is supplied to each zone. For all building vintages, the total
return plus Restroom exhaust flow rate for each system (no Restroom exhaust in Basement) is set
to 90 % of the total supply airflow rate. The building is neutrally pressurized between 6:00 a.m.
and 7:00 a.m. weekdays and Saturdays when the system operates but no outside air is being
supplied.
Schedules:
All HVAC and exhaust fans operate on the following schedule:
Weekdays: on from 6:00 a.m. to 10:00 p.m., off otherwise
Saturday: on from 6:00 a.m. to 6:00 p.m., off otherwise
Sunday, holidays: off all day
The outside air for the HVAC systems operate on the following schedule:
Weekdays: on from 7:00 a.m. to 10:00 p.m., off otherwise
Saturday: on from 7:00 a.m. to 6:00 p.m., off otherwise
Sunday, holidays: off all day
Occupants:
The peak number of people for each zone is listed in Table A10. Occupants in all building zones
are scheduled according to Figure A8. There is a different occupancy schedule for weekdays and
Saturdays. Sundays and holidays are unoccupied.
76
B
1
1
1
1
1
1
Basement
Perimeter North
Perimeter East
Perimeter South
Perimeter West
Core
Restroom
“Bottom” system total
Perimeter North
Perimeter East
Perimeter South
Perimeter West
Core
Restroom
“Middle” system total
Perimeter North
Perimeter East
Perimeter South
Perimeter West
Core
Restroom
“Top” system total
12
12
12
12
12
12
2-11
2-11
2-11
2-11
2-11
2-11
Floor
Zone
7.20
1.26
1.71
1.45
1.99
8.84
N/A
15.26
1.30
1.79
1.53
2.12
9.50
N/A
16.24
1.37
1.75
1.55
2.19
9.25
N/A
16.11
New
Supply
N/A
14.35
N/A
14.46
N/A
13.58
6.48
Return
9.62
1.48
1.84
1.66
2.14
10.40
N/A
17.52
1.49
1.90
1.73
2.25
10.92
N/A
18.30
1.51
1.83
1.71
2.28
10.21
N/A
17.55
77
N/A
15.64
N/A
16.38
N/A
15.62
8.65
Post-1980
Supply Return
8.93
1.50
1.93
1.79
2.25
10.38
N/A
17.86
1.53
1.99
1.87
2.36
10.97
N/A
18.72
1.63
1.90
1.89
2.45
9.99
N/A
17.85
N/A
15.94
N/A
16.80
N/A
15.94
8.03
Pre-1980
0.81
0.95
0.95
1.22
5.11
N/A
0.76
1.00
0.93
1.18
5.49
N/A
Return
Grille
Size
(m2)
N/A
0.75
0.96
0.90
1.13
5.20
N/A
Table A11 Summary of VAV system flow rates (m3/s) in Large Office
1.20
0.20
0.26
0.23
0.30
1.40
0
2.40
0.19
0.26
0.23
0.30
1.41
0
2.40
0.21
0.26
0.24
0.32
1.37
0
2.40
Outside Air
(m3/s)
0
0
0
0
0
0.15
0
0
0
0
0
0.15
0
0
0
0
0
0
0.15
Exhaust
air
(m3/s)
Occupancy Schedules
1
Weekday
0.9
Saturday
0.8
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A10 Occupancy schedule for Large Office
A2.6.
Primary School
Table A12 summarizes the zones modeled in CONTAM for the Primary School, their respective
sizes, and maximum occupancy.
Geometry:
6871 m2 footprint (“E” shape), one-story building with flat roof. The EnergyPlus model has
25 zones. Most of the large spaces that are typical of schools are modeled as individual zones.
Some of the classrooms are grouped together to form a single thermal zone, such as the “Mult”
classrooms.
The CONTAM model was altered to create more realistic corridors with reasonable circulation
patterns. In EnergyPlus, the Bathroom and Library Media Center blocked access to the
Pod 3 corridor. This also prevented access to that section of the building from the Main Corridor.
In CONTAM, a 3 m wide path was carved out of the Library Media Center and the Bathroom to
connect the Main Corridor to Pod 3 (shaded in Figure A11).
In EnergyPlus, the Mechanical Room extended from the Lobby to the Bathroom, blocking access
from the Main Corridor to the Cafeteria, Kitchen, and Gym. In CONTAM, the Mechanical Room
was shortened to allow the Main Corridor to provide access to the Cafeteria, Kitchen, and Gym
(shaded in Figure A11). These changes make the Main Corridor larger (shaded in Figure A11)
and the Library Media Center, Bathroom, and Mechanical Room smaller in the CONTAM model
than in the EnergyPlus model. Nevertheless, the occupancies and ventilation rates of the zones
were not changed so that the CONTAM model matches the EnergyPlus model.
78
Table A12 Summary of zones in Primary School
Zone
Area (m2)
Height (m)
Corner (“Cor”) Class 1 Pod 1
Multiple (“Mult”) Class 1 Pod 1
Corridor (“Corr”) Pod 1
Cor Class 2 Pod 1
Mult Class 2 Pod 1
Cor Class 1 Pod 2
Mult Class 1 Pod 2
Corr Pod 2
Cor Class 2 Pod 2
Mult Class 2 Pod 2
Cor Class 1 Pod 3
Mult Class 1 Pod 3
Corr Pod 3
Cor Class 2 Pod 3
Mult Class 2 Pod 3
Computer Class
Main Corridor
Lobby
Mechanical Room
Bathroom
Offices
Library Media Center
Gym
Kitchen
Cafeteria
99
477
192
99
477
99
477
192
99
477
99
477
192
99
315
162
708
171
156
160
441
363
357
168
315
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
79
Maximum
occupancy
24.75
119.25
19.20
24.75
119.25
24.75
119.25
19.20
24.75
119.25
24.75
119.25
19.20
24.75
78.75
48.65
54.6
0
0
19.00
22.05
91.72
107.21
25.19
226.04
9m
C class 2
Pod 3
3m
9m
Mult class 2 pod 3
Computer
class
3m
Library
media
center
Corridor pod 3
C class 1
pod 3
Mult class1 pod 3
10 m
9m
82 m
Bath
C class 2
pod 2
3m
9m
15 m
Kitchen
8m
Mult class 2 pod 2
16 m
Corridor pod 2
C class 1
Pod 2
Cafeteria
Main
Corridor
Mult class 1 pod 2
Gym
17 m
9m
9m
42 m
C class 2
pod 1
3m
9m
Mech.
Mult class 2 pod 1
Offices
Corridor pod 1
C class 1
pod 1
11 m
Mult class1 pod 1
21 m
Lobby
35 m
18 m
13 m
6m
21 m
104 m
Figure A11 Plan of Primary School (height 4.0 m)
Large interior leakage paths were defined as follows:
Between the Kitchen and Cafeteria zones, a single large leakage path of 42 m2 (50 % of the
total wall area between the two spaces) is modeled;
Between each Pod’s corridor and the Main Corridor, a 4.0 m2 open doorway is modeled;
Between the Lobby and Main Corridor, two 4.0 m2 open doorways are modeled;
Between the Bathroom and Main Corridor, a 0.186 m2 transfer grille is modeled.
HVAC systems:
For all building vintages, the EnergyPlus model has three CAV and four VAV systems. The
Kitchen, Gym, and Cafeteria each have a CAV system. The VAV systems are zoned as follows:
VAV Pod 1: serves the zones in Pod 1
VAV Pod 2: serves the zones in Pod 2
VAV Pod 3: serves the zones in Pod 3
VAV Other: serves the Computer Class, Main Corridor, Lobby, Mechanical Room,
Bathroom, Offices, and Library Media Center (7 zones total)
80
The design supply flow rate calculated by EnergyPlus for each VAV system is used as the supply
flow rate for each constant-volume system modeled in CONTAM for simplicity. The systems
modeled in CONTAM are still referred to as “VAV” systems in the body of this text. Varying
the supply flow rate can be implemented in CONTAM using controls and/or schedules by users
who wish to do so. The supply air, return air, outside air, and exhaust flow rates modeled in
CONTAM are listed in Table A13 for all building vintages.
In EnergyPlus, there was a Cafeteria exhaust fan (1.3554 m3/s) in addition to the Kitchen exhaust
fan (0.2016 m3/s). It was included in order to transfer air from the Cafeteria to the Kitchen. This
is modeled in CONTAM using a large opening between the Cafeteria and Kitchen zones
(see above), and one larger exhaust fan in the Kitchen (1.557 m3/s).
In EnergyPlus, neutral building pressurization is modeled in all zones. To pressurize the building
in CONTAM, less air is returned than is supplied to each zone. For all building vintages, the
return airflow rate is set to 90 % of the supply airflow rate. The return airflow from the
Bathroom is reduced by the Bathroom exhaust (0.28 m3/s). The return airflow from the Kitchen
is reduced by 0.20 m3/s and the return airflow from the Cafeteria is reduced by 1.36 m3/s to allow
for the Kitchen exhaust (1.56 m3/s).
Schedules:
All HVAC and exhaust fans operate on the following schedule:
Weekdays: on from 6:00 a.m. to 9:00 p.m., off otherwise
Weekends and holidays: off all day
Outside air is supplied according to this schedule as well. Summer weekday schedules, as
discussed in Section A1, are not used in the HVAC/fan schedules.
Occupants:
The peak number of people for each zone is listed in Table A12. Occupants in all building zones
are scheduled according to Figure A12 to Figure A13. Sundays and holidays are unoccupied.
There are four different occupant schedules for the building. The occupancy schedules for the
Gym and Cafeteria are shown in Figure A12. The occupancy schedule for the Offices is shown
in Figure A13. Also shown in Figure A13 is the occupancy schedule for the remaining zones
(referred to as “Class” occupancy). All of the schedules in Figure A12 to Figure A13 consider
“summer” to be July 1 through August 31. “School year” is the remainder of the year.
81
Table A13 Summary of HVAC system flow rates (m3/s) in Primary School
Zone
Cor Class 1 Pod 1
Mult Class 1 Pod 1
Corr Pod 1
Cor Class 2 Pod 1
Mult Class 2 Pod 1
VAV-Pod 1 total
Cor Class 1 Pod 2
Mult Class 1 Pod 2
Corr Pod 2
Cor Class 2 Pod 2
Mult Class 2 Pod 2
VAV-Pod 2 total
Cor Class 1 Pod 3
Mult Class 1 Pod 3
Corr Pod 3
Cor Class 2 Pod 3
Mult Class 2 Pod 3
VAV-Pod 3 total
Computer Class
Main Corridor
Lobby
Mechanical Room
Bathroom
Offices
Library Media Center
VAV-Other total
Gym (CAV 2:5)
Kitchen (CAV 1:6)
Cafeteria (CAV 2:7)
New
Supply
0.59
0.56
0.42
1.45
1.29
4.30
0.58
0.56
0.41
1.41
1.29
4.25
0.58
0.56
0.42
1.42
0.89
3.87
0.50
0.93
0.39
0.41
0.55
1.10
1.10
4.99
1.14
0.62
2.27
Return
0.53
0.50
0.37
1.31
1.16
3.87
0.52
0.50
0.37
1.27
1.16
3.82
0.52
0.51
0.38
1.28
0.80
3.48
0.45
0.84
0.35
0.37
0.22
0.99
0.99
4.21
1.03
0.42
0.68
Post-1980
Supply Return
0.61
0.55
0.58
0.53
0.50
0.45
1.53
1.38
1.38
1.24
4.61
4.15
0.61
0.54
0.59
0.53
0.50
0.45
1.50
1.35
1.38
1.24
4.57
4.11
0.61
0.55
0.59
0.53
0.50
0.45
1.50
1.35
0.94
0.85
4.14
3.73
0.53
0.48
1.10
0.99
0.44
0.39
0.31
0.28
0.51
0.18
1.18
1.06
1.20
1.08
5.28
4.47
1.07
0.96
0.60
0.40
2.27
0.68
82
Pre-1980
Supply Return
0.75
0.68
0.72
0.65
0.64
0.58
1.96
1.76
1.69
1.52
5.77
5.19
0.75
0.67
0.72
0.65
0.64
0.58
1.92
1.73
1.69
1.52
5.72
5.14
0.75
0.67
0.73
0.66
0.65
0.58
1.92
1.73
1.15
1.04
5.19
4.67
0.64
0.58
1.43
1.29
0.51
0.46
0.41
0.37
0.66
0.31
1.51
1.36
1.47
1.32
6.63
5.69
1.07
0.96
0.70
0.50
2.27
0.68
Outside
Air (m3/s)
0.20
0.95
0.10
0.20
0.95
2.40
0.20
0.95
0.10
0.20
0.95
2.40
0.20
0.95
0.10
0.20
0.95
2.40
0.39
0.27
0.09
0.06
0.30
0.22
0.73
2.07
1.07
0.20
2.26
Exhaust
air (m3/s)
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0.28
0
0
0
1.56
0
Occupancy Schedules
1
Gym - School year
0.9
Gym - Summer
0.8
Cafeteria - School year
Cafeteria - Summer
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A12 Occupancy schedules for Primary School (Gym, Cafeteria)
Occupancy Schedules
1
Offices - School year
0.9
Offices - Summer
Class - School year
0.8
Class - Summer
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A13 Occupancy schedules for Primary School (Offices, Class)
83
A2.7.
Secondary School
Table A14 summarizes the zones modeled in CONTAM for the Secondary School, their
respective sizes, and maximum occupancy.
Geometry:
19 592 m2 footprint (“E” shape), two-story building with flat roof. The EnergyPlus model has
25 zones on the first floor and 21 zones on the second floor. The first floor has an 11 902 m2
footprint. The second floor is stacked on top of the first floor with a footprint of 7690 m2. Both
floors have the same floor plan except that the Library Media Center on the second floor stacks
on top of the Cafeteria and Kitchen. Most of the large spaces that are typical of schools are
modeled as individual zones. Some of the classrooms are grouped together to form a single
thermal zone. Three spaces (Auditorium, Gym, and Auxiliary Gym) on the first floor are twostories (8 m) high. The remaining zones on both floors are all 4 m high.
The CONTAM model was altered to create more realistic corridors with reasonable circulation
patterns. In EnergyPlus, the first and second floor Bathroom blocked access to the Pod 3
Corridor. This also prevented access to those sections of the building from the first and second
floor Main Corridor. In CONTAM, a 3 m wide path was carved out of the first and second floor
Bathroom to provide access from the Main Corridor to the Pod 3 (shaded in Figure A14 and
Figure A15).
In EnergyPlus, the first floor Mechanical Room blocked access from the Main Corridor to the
Cafeteria, Kitchen, and Auxiliary Gym. In EnergyPlus, the second floor Mechanical Room
blocked access from the Main Corridor to the Library Media Center. In CONTAM, the first and
second floor Mechanical Room were moved and carved out of the Gym (shaded in Figure A14
and Figure A15). In CONTAM, the first floor Kitchen was also shortened to provide access from
the Main Corridor to the Cafeteria and Auxiliary Gym (shaded in Figure A14).
These changes make the first and second floor Main Corridor larger (shaded in Figure A14 and
Figure A15) and the first and second floor Bathroom, first floor Kitchen, and first floor Gym
smaller in the CONTAM model than in the EnergyPlus model. Nevertheless, the occupancies
and ventilation rates of the zones were not changed so that the CONTAM model matches the
EnergyPlus model.
84
Table A14 Summary of zones in Secondary School
Zone
Floor
Area (m2)
Height (m)
Corner (“Cor”) Class 1 Pod 1
Multiple (“Mult”) Class 1 Pod 1
Corridor (“Corr”) Pod 1
Cor Class 2 Pod 1
Mult Class 2 Pod 1
Cor Class 1 Pod 2
Mult Class 1 Pod 2
Corr Pod 2
Cor Class 2 Pod 2
Mult Class 2 Pod 2
Cor Class 1 Pod 3
Mult Class 1 Pod 3
Corr Pod 3
Cor Class 2 Pod 3
Mult Class 2 Pod 3
Main Corridor
Lobby
Bathroom
Offices
Gym
Auxiliary Gym
Auditorium
Kitchen
Cafeteria
Mechanical Room
Cor Class 1 Pod 1
Mult Class 1 Pod 1
Corr Pod 1
Cor Class 2 Pod 1
Mult Class 2 Pod 1
Cor Class 1 Pod 2
Mult Class 1 Pod 2
Corr Pod 2
Cor Class 2 Pod 2
Mult Class 2 Pod 2
Cor Class 1 Pod 3
Mult Class 1 Pod 3
Corr Pod 3
Cor Class 2 Pod 3
Mult Class 2 Pod 3
Main Corridor
Lobby
Bathroom
Offices
Library Media Center
Mech
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
99
477
320
99
477
99
477
320
99
477
99
477
320
99
477
1524
210
195
532
1976
1248
988
189
624
342
99
477
320
99
477
99
477
320
99
477
99
477
320
99
477
1497
210
195
532
840
342
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
8.0
8.0
8.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
4.0
85
Maximum
occupancy
24.75
119.25
32.00
24.75
119.25
24.75
119.25
32.00
24.75
119.25
24.75
119.25
32.00
24.75
119.25
0.00
0.00
21.00
26.60
1976.00
374.8
988.00
32.4
448.92
3.42
24.75
119.25
32.00
24.75
119.25
24.75
119.25
32.00
24.75
119.25
24.75
119.25
32.00
24.75
119.25
0.00
0.00
21.00
26.60
193.10
3.42
104 m
9m
5m
9m
17 m
9m
5m
9m
18 m
9m
5m
9m
11 m
C class 1
pod 1
C class 2
pod 1
C class 1
Pod 2
C class 2
pod 2
C class 1
pod 3
C class 2
Pod 3
141 m
12m
9m
15 m
Lobby
Main
Corridor
3m
Bath
38 m
Offices
Gym
Mech
Main Corridor
Auditorium
86
24 m
Auxiliary
Gym
3m 21m
Kitchen
Cafeteria
Figure A14 First floor plan of Secondary School (height 4.0 m)
53 m
Mult class1 pod 1
Corridor pod 1
Mult class 2 pod 1
Mult class 1 pod 2
Corridor pod 2
Mult class 2 pod 2
Mult class1 pod 3
Corridor pod 3
Mult class 2 pod 3
14 m
52 m
9m
26 m
104 m
9m
5m
9m
17 m
9m
5m
9m
18 m
9m
5m
9m
11 m
C class 1
pod 1
C class 2
pod 1
C class 1
Pod 2
C class 2
pod 2
C class 1
pod 3
C class 2
Pod 3
141 m
12m
9m
15 m
Lobby
Main
Corridor
3m
Bath
38 m
Offices
Two story
gym –
phantom
zone
Mech
Main Corridor
Two story
Auditorium
– phantom
zone
87
24 m
Two story
Auxiliary
Gym –
phantom
zone
Library/
media
center
Figure A15 Second floor plan of Secondary School (height 4.0 m)
53 m
Mult class1 pod 1
Corridor pod 1
Mult class 2 pod 1
Mult class 1 pod 2
Corridor pod 2
Mult class 2 pod 2
Mult class1 pod 3
Corridor pod 3
Mult class 2 pod 3
14 m
52 m
9m
26 m
Large interior leakage paths were defined as follows:
Between the Kitchen and Cafeteria zones, a single large leakage path of 42 m2 (50 % of the
total wall area between the two spaces) is modeled;
The wall between each Pod’s corridor and the Main Corridor is modeled with a 4.0 m2
open doorway;
Two 4.0 m2 open doorways are modeled in the wall connecting the Lobby to the Main
Corridor;
Each Bathroom is modeled with a 0.186 m2 transfer grille in the door between the
Bathroom and the Main Corridor.
HVAC systems:
For all building vintages, the EnergyPlus model has five CAV and four VAV systems. The Gym,
Auxiliary Gym, Auditorium, Kitchen, and Cafeteria each have a CAV system. The VAV systems
are zoned as follows:
VAV Pod 1: serves the zones in Pod 1, first and second floor
VAV Pod 2: serves the zones in Pod 2, first and second floor
VAV Pod 3: serves the zones in Pod 3, first and second floor
VAV Other: serves the first and second floors Main Corridor, Lobby, Mechanical Room,
Bathroom, Offices, and the second floor Library Media Center (11 zones total)
The design supply flow rate calculated by EnergyPlus for each VAV system is used as the supply
flow rate for each constant-volume system modeled in CONTAM for simplicity. The systems
modeled in CONTAM are still referred to as “VAV” systems in the body of this text. Varying
the supply flow rate can be implemented in CONTAM using controls and/or schedules by users
who wish to do so. The supply air, return air, outside air, and exhaust flow rates modeled in
CONTAM are listed in Table A15 for all three building vintages.
In EnergyPlus, there was a Cafeteria exhaust fan (1.63 m3/s) in addition to the Kitchen exhaust
fan (0.26 m3/s). It was included in order to transfer air from the Cafeteria to the Kitchen. This is
modeled in CONTAM using a large opening between the Cafeteria and Kitchen zones
(see above), and one larger exhaust fan in the Kitchen (1.89 m3/s).
In EnergyPlus, neutral building pressurization is modeled in all zones. To pressurize the building
in CONTAM, less air is returned than is supplied to each zone. For all building vintages, the
return airflow rate is set to 90 % of the supply airflow rate. The return airflows from the first and
second floor Bathrooms are reduced by the Bathroom exhausts (0.3 m3/s each). The return air
from the Kitchen is equal to the supply airflow rate minus the outside air requirement, and the
return air for the Cafeteria is reduced by 1.63 m3/s, to allow makeup air for the Kitchen exhaust
(1.89 m3/s). The Kitchen is thus neutrally pressurized.
88
Corner (“Cor”) Class 1 Pod 1
Multiple (“Mult”) Class 1 Pod 1
Corridor (“Corr”) Pod 1
Cor Class 2 Pod 1
Mult Class 2 Pod 1
Cor Class 1 Pod 1
Mult Class 1 Pod 1
Corr Pod 1
Cor Class 2 Pod 1
Mult Class 2 Pod 1
VAV-Pod 1 Total
Cor Class 1 Pod 2
Mult Class 1 Pod 2
Corr Pod 2
Cor Class 2 Pod 2
Mult Class 2 Pod 2
Cor Class 1 Pod 2
Mult Class 1 Pod 2
Corr Pod 2
Cor Class 2 Pod 2
Mult Class 2 Pod 2
VAV-Pod 2 Total
Cor Class 1 Pod 3
Mult Class 1 Pod 3
Corr Pod 3
Cor Class 2 Pod 3
Mult Class 2 Pod 3
Cor Class 1 Pod 3
Mult Class 1 Pod 3
Corr Pod 3
Cor Class 2 Pod 3
Mult Class 2 Pod 3
Zone
Floor New
Supply
1
0.44
1
0.95
1
0.41
1
0.41
1
0.95
2
0.64
2
1.64
2
0.78
2
0.61
2
1.48
8.31
1
0.43
1
0.95
1
0.29
1
0.40
1
0.95
2
0.63
2
1.61
2
0.77
2
0.61
2
1.48
8.13
1
0.43
1
0.95
1
0.29
1
0.41
1
0.95
2
0.64
2
1.91
2
0.78
2
0.62
2
1.79
Return
0.39
0.86
0.37
0.36
0.86
0.57
1.48
0.70
0.55
1.33
7.48
0.38
0.86
0.26
0.36
0.86
0.57
1.45
0.69
0.55
1.33
7.32
0.38
0.86
0.26
0.37
0.86
0.57
1.72
0.70
0.56
1.61
89
Post-1980
Supply Return
0.49
0.44
0.99
0.89
0.42
0.37
0.46
0.41
0.95
0.86
0.67
0.60
1.72
1.55
0.77
0.69
0.64
0.58
1.57
1.41
8.68
7.81
0.48
0.43
1.09
0.98
0.35
0.32
0.46
0.41
0.95
0.86
0.66
0.60
1.71
1.54
0.76
0.69
0.64
0.58
1.58
1.42
8.70
7.83
0.48
0.43
1.09
0.98
0.36
0.32
0.46
0.42
0.98
0.88
0.67
0.60
2.00
1.80
0.78
0.70
0.65
0.58
1.88
1.69
Pre-1980
Supply Return
0.57
0.51
1.18
1.06
0.46
0.42
0.53
0.48
1.02
0.92
0.81
0.73
2.14
1.93
0.98
0.88
0.78
0.70
1.88
1.69
10.35
9.31
0.56
0.51
1.27
1.14
0.40
0.36
0.53
0.48
1.02
0.92
0.80
0.72
2.12
1.91
0.97
0.88
0.78
0.70
1.89
1.70
10.35
9.32
0.56
0.51
1.28
1.15
0.41
0.36
0.54
0.49
1.06
0.95
0.81
0.73
2.42
2.18
0.99
0.89
0.78
0.70
2.20
1.98
4.93
4.93
Outside
Air (m3/s)
Table A15 Summary of HVAC system flow rates (m3/s) in Secondary School
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Exhaust
air (m3/s)
0
0
0
0
0
0
0
0
0
0
Zone
VAV-Pod 3 Total
Main Corridor
Lobby
Bathroom
Offices
Mechanical Room
Main Corridor
Lobby
Bathroom
Offices
Library Media Center
Mechanical Room
VAV-Other Total
Gym (CAV 1:5)
Auxiliary Gym (CAV 2:6)
Auditorium (CAV 3:7)
Kitchen (CAV 4:8)
Cafeteria (CAV 5:9)
Floor New
8.77
1
1.14
1
0.24
1
0.53
1
0.91
1
1.05
2
2.81
2
0.54
2
0.65
2
1.66
2
2.53
2
0.76
12.80
1
19.79
1
4.97
1
7.90
1
0.55
1
4.49
7.89
1.03
0.22
0.17
0.82
0.95
2.53
0.48
0.28
1.49
2.28
0.68
10.92
17.78
4.47
7.11
0.29
2.41
90
Post-1980
9.34
8.41
1.80
1.62
0.32
0.28
0.70
0.33
1.14
1.03
0.89
0.80
2.77
2.49
0.60
0.54
0.86
0.48
1.77
1.59
2.45
2.21
0.51
0.46
13.81
11.83
19.79
17.78
3.75
3.38
7.90
7.11
0.56
0.30
4.49
2.41
Pre-1980
11.04
9.94
2.00
1.80
0.35
0.31
0.76
0.38
1.30
1.17
0.91
0.82
3.58
3.22
0.68
0.61
0.98
0.58
2.19
1.97
2.97
2.67
0.68
0.61
16.39
14.15
19.79
17.78
4.43
3.99
7.90
7.11
0.59
0.33
4.49
2.41
4.65
19.76
3.75
7.90
0.26
4.49
Outside
Air (m3/s)
4.93
0
0
0
1.89
0
Exhaust
air (m3/s)
0
0
0.30
0
0
0
0
0.30
0
0
0
Schedules:
All HVAC and exhaust fans operate on the following schedule:
Weekdays: on from 6:00-21:00, off otherwise
Weekends and holidays: off all day
Outside air is supplied according to this schedule as well. Summer weekday schedules, as
discussed in Section A1, are not used in the HVAC/fan schedules.
Occupants:
The peak number of people for each zone is listed in Table A14. Occupants in all building zones
are scheduled according to Figure A16 to Figure A17. Sundays and holidays are unoccupied.
There are six different occupant schedules for the building. The occupancy schedules for the
Gym (and Auxiliary Gym), Cafeteria, and Auditorium are shown in Figure A16. The occupancy
schedule for the Offices is shown in Figure A17. Also shown in Figure A17 is the occupancy
schedule for the remaining zones (referred to as “Class” occupancy). There is also an Extended
Class occupancy schedule in Figure A17. They are for the “Mult Class 1” “Mult Class 2” zones
in Pod 3 on the second floor. The Extended Class and Class occupancy schedules are the same
except the Extended Class occupancy schedule has greater and constant occupancy from 9:00
a.m. to 9:00 p.m. both during the school year and summer. All of the schedules in Figure A16 to
Figure A17 consider “summer” to be July 1 through August 31. “School year” is the remainder
of the year.
Occupancy Schedules
1
Gym - School year
0.9
Gym - Summer
0.8
Cafeteria - School year
Cafeteria - Summer
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A16 Occupancy schedules for Secondary School (Gym, Cafeteria, and Auditorium)
91
Occupancy Schedules
1
Offices - School year
0.9
Offices - Summer
Class - School year
0.8
Class - Summer
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A17 Occupancy schedules for Secondary School (Offices, Class)
A2.8.
Stand-Alone Retail
Table A16 summarizes the zones modeled in CONTAM for the Stand-Alone Retail, their
respective sizes, and maximum occupancy.
Table A16 Summary of zones in Stand-Alone Retail
Zone
Area (m2)
Height (m)
Back Space
Core Retail
Point of Sale
Front Retail
Front Entry
Restroom
352
1600
151
151
12
28
6.1
6.1
6.1
6.1
6.1
6.1
Maximum
occupancy
13.63
258.40
24.35
24.35
1.94
0
Geometry:
2294 m2 footprint, single-story building with flat roof. The EnergyPlus model has five zones. In
the CONTAM model, a Restroom (shaded in Figure A18) with a footprint of 4 m 7 m was
carved out of the Back Space.
92
4m
Back space
Restroom
7m
Core retail
42.27 m
29.27 m
Front entry
Point of
sale
Front retail
3m
3m
21.135 m
4m
21.135 m
54.27 m
Figure A18 Floor plan of Stand-Alone Retail (height 6.1 m)
Large interior leakage paths were defined as follows:
Between Back Space and Core Retail, a single large leakage path of 3.0 m2 is modeled;
Between Core Retail and Point of Sale, a single large leakage path of 96.7 m2 (75 % of the
total wall area between the spaces) is modeled;
Between Core Retail and Front Retail, a single large leakage path of 96.7 m2 (75 % of the
total wall area between the spaces) is modeled;
Between the Restroom and Back space, a 0.372 m2 transfer grille is modeled.
HVAC systems:
For all building vintages, the building has five packaged constant-volume single-zone systems.
Similarly, each zone has a constant-volume system in CONTAM. The supply air, return air,
outside air, and exhaust flow rates modeled in CONTAM are listed in Table A17 for all three
building vintages. The exhaust flow rate for the Restroom was modeled only in CONTAM, not
in EnergyPlus.
The Front Entry has a unit heater in EnergyPlus that recirculates air locally within the zone and
does not impact whole-building airflow or introduce outside air. Therefore, the unit heater is not
modeled in CONTAM.
In EnergyPlus, neutral building pressurization is modeled in all zones. To pressurize the building
in CONTAM, less air is returned than is supplied to each zone. For all building vintages, the
return airflow rate is set to 90 % of the supply airflow rate.
93
Table A17 Summary of HVAC system flow rates (m3/s) in Stand-Alone Retail
Zone
Back Space
Core Retail
Point of Sale
Front Retail
Restroom
New
Supply
Return
Post-1980
Supply Return
Pre-1980
Supply Return
1.44
4.72
0.88
0.66
N/A
1.30
4.25
0.79
0.59
N/A
3.31
7.21
1.47
1.47
N/A
3.57
7.69
1.58
1.58
N/A
3.03
6.49
1.32
1.32
N/A
3.29
6.92
1.42
1.42
N/A
Outside
Air
(m3/s)
0.29
2.40
0.23
0.23
0
Exhaust
air
(m3/s)
0
0
0
0
0.05
Schedules:
All HVAC and exhaust fans operate on the following schedule:
Weekdays: on from 6:00 a.m. to 9:00 p.m., off otherwise
Saturday: on from 6:00 a.m. to 10:00 p.m., off otherwise
Sunday, holidays: on from 8:00 a.m. to 7:00 p.m., off otherwise
Outside air is supplied according to this schedule as well.
Occupants:
The peak number of people for each zone is listed in Table A16. Occupants in all building zones
are scheduled according to Figure A19. There is a different occupancy schedule for weekdays,
Saturdays, and Sundays/ holidays.
Occupancy Schedules
1
Weekday
0.9
Saturday
Sunday, Holiday
0.8
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A19 Occupancy schedule for Stand-Alone Retail
94
A2.9.
Strip Mall
Table A18 summarizes the zones modeled in CONTAM for the Strip Mall, their respective sizes,
and maximum occupancy.
Table A18 Summary of zones in Strip Mall
Zone
Area (m2)
Height (m)
Large Stores (LS)
LS storage
LS restroom
Small Stores (SS)
SS storage
SS restroom
261.29
52.81
34.29
130.64
39.55
4.00
5.18
5.18
5.18
5.18
5.18
5.18
Maximum
occupancy
56.25
0
0
28.12
0
0
Geometry:
2090 m2 footprint, single-story building with flat roof. The EnergyPlus model has 10 zones.
There are two “Large Stores” (LS) and eight “Small Stores” (SS). In the CONTAM model, each
store is sub-divided into three zones. The rear 25 % of each store was divided into Storage and
Restroom zones (Storage zones are shown in gray and Restrooms shown in black in Figure A20).
2 m x 2m restroom, typical for SS
Storage
9.24 m 6 m
5.715m
LS
1
15.24 m
SS
1
SS
2
SS
3
SS
4
LS
2
7.62m 7.62m 7.62m 7.62m
15.24 m
SS
5
SS
6
SS
7
SS
8
22.86 m
7.62m 7.62m 7.62m 7.62m
91.44 m
Figure A20 Floor plan of Strip Mall (height 5.18 m)
Large interior leakage paths were defined as follows:
Between the store and storage zones, a 4 m2 opening is modeled;
Between the Restrooms in the Large Stores and Storage zones, a 0.186 m2 transfer grille is
modeled;
Between the Restrooms in the Small Stores and Storage zones, a 0.025 m2 door undercut is
modeled.
95
HVAC systems:
For all building vintages, the EnergyPlus model has 10 packaged constant-volume single-zone
systems. Similarly, each zone has a constant-volume system in CONTAM. The supply air, return
air, outside air, and exhaust flow rates modeled in CONTAM are listed in Table A19 for all three
building vintages. The exhaust flow rates for the Restrooms were modeled only in CONTAM,
not in EnergyPlus.
In CONTAM, the design supply flow rate calculated by EnergyPlus for each constant-volume
system is split between the store and storage zones. Seventy five percent of the design supply
flow rate is directed to the store and 25 % to the storage zone in CONTAM. In EnergyPlus,
neutral building pressurization is modeled in all zones. To pressurize the building in CONTAM,
less air is returned than is supplied to each zone. For all building vintages, the return plus
Restroom exhaust flow rate for each zone is set to 90 % of the supply airflow rate.
Table A19 Summary of HVAC system flow rates (m3/s) in Strip Mall
Zone
New
Post-1980
Pre-1980
Outside
Supply Return Supply Return Supply Return Air
(m3/s)
LS 1 (CAV 1:1)
1.38
1.22
2.50
2.23
2.72
2.42
0.52
LS 2 (CAV 6:6)
1.02
0.89
2.01
1.78
2.16
1.92
0.52
SS 1 (CAV 2:2)
0.65
0.56
1.19
1.05
1.25
1.10
0.26
SS 2 (CAV 3:3)
0.59
0.51
1.01
0.88
1.09
0.96
0.26
SS 3 (CAV 4:4)
0.59
0.51
1.01
0.88
1.09
0.96
0.26
SS 4 (CAV 5:5)
0.58
0.50
1.01
0.88
1.09
0.96
0.26
SS 5 (CAV 7:7)
0.53
0.45
1.01
0.88
1.09
0.96
0.26
SS 6 (CAV 8:8)
0.53
0.45
1.01
0.88
1.09
0.96
0.26
SS 7 (CAV 9:9)
0.53
0.45
1.01
0.88
1.09
0.96
0.26
SS 8 (CAV 10:10) 0.60
0.52
1.50
1.33
1.65
1.46
0.26
LS Restroom
N/A
N/A
N/A
N/A
N/A
N/A
0
SS Restroom
N/A
N/A
N/A
N/A
N/A
N/A
0
Note: The supply and return rates are the sum of the rates to/from the store and storage zones.
Exhaust
air
(m3/s)
0
0
0
0
0
0
0
0
0
0
0.03
0.03
Schedules:
All HVAC and exhaust fans operate on the following schedule:
Weekdays: on from 6:00 a.m. to 9:00 p.m., off otherwise
Saturday: on from 6:00 a.m. to 10:00 p.m., off otherwise
Sunday, holidays: on from 8:00 a.m. to 7:00 p.m., off otherwise
Outside air is supplied according to this schedule as well.
Occupants:
The peak number of people for each zone is listed in Table A18. Occupants in all building zones
are scheduled according to Figure A21. There is a different occupancy schedule for weekdays,
Saturdays, and Sundays/ holidays.
96
Occupancy Schedules
1
Weekday
0.9
Saturday
Sunday, Holiday
0.8
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A21 Occupancy schedule for Strip Mall
A2.10. Supermarket
Table A20 summarizes the zones modeled in CONTAM for the Supermarket, their respective
sizes, and maximum occupancy.
Geometry:
4181 m2 footprint, single-story building with flat roof. The EnergyPlus model has six zones. In
the CONTAM model, a Restroom (shaded in Figure A22) with a footprint of 4 m 4 m was
carved out of Dry Storage.
Table A20 Summary of zones in Supermarket
Zone
Area (m2)
Height (m)
Office
Dry Storage
Deli
Sales
Produce
Bakery
Restroom
89
606
225
2325
711
209
16
6.10
6.10
6.10
6.10
6.10
6.10
6.10
97
Maximum
occupancy
4.78
22.31
19.35
200.20
61.26
18.00
0
4m
Dry Storage
4m
Restroom
Office
8.98 m
Deli
52.79 m
Produce
43.82 m
Sales
22.70 m
Bakery
1
6.23 m
53.06 m
21.12 m
9.90 m
79.19 m
Figure A22 Floor plan of Supermarket (height 6.1 m)
Large interior leakage paths were defined as follows:
Between Produce and Sales, a single large leakage path of 6.0 m2 is modeled;
Between Bakery and Sales, a single large leakage path of 64.4 m2 (50 % of the total wall
area between the spaces) is modeled;
Between Deli and Sales, a single large leakage path of 69.2 m2 (50 % of the total wall area
between the spaces) is modeled;
Between Dry Storage and Sales zone, a single large leakage path of 6.0 m2 is modeled;
Between Restroom and Dry Storage zone, a 0.186 m2 transfer grille is modeled.
HVAC systems:
For all building vintages, the EnergyPlus model has five packaged constant-volume single-zone
systems. Similarly, each zone has a constant-volume system in CONTAM. The supply air, return
air, outside air, and exhaust flow rates modeled in CONTAM are listed in Table A21 for all three
building vintages. The exhaust flow rates for the Restrooms were modeled only in CONTAM,
not in EnergyPlus.
In EnergyPlus, there was a Sales exhaust fan (1.08 m3/s) in addition to the Bakery exhaust fan
(0.35 m3/s) and Deli exhaust fan (0.34 m3/s). The Sales exhaust fan was included in order to
transfer air from the Sales zone to the Deli. This is modeled in CONTAM using a large opening
between the Sales and Deli zones (see above), and one larger exhaust fan in the Deli (1.42 m3/s).
The sum of the Sales and Deli exhaust rates in EnergyPlus is 1.42 m3/s.
In EnergyPlus, neutral building pressurization is modeled in all zones. To pressurize the building
in CONTAM, less air is returned than is supplied to each zone. For the Dry Storage, Office, and
Produce zones, the return airflow rate is the larger of (a) 90 % of the supply airflow rate and
(b) supply airflow rate minus outside air requirement.
98
In CONTAM, the Bakery is neutrally pressurized. The return airflow rate is the supply airflow
rate minus the exhaust rate for all building vintages.
In CONTAM, the Deli is depressurized. The return airflow rate is the supply airflow rate minus
the outside air rate for all building vintages. The Deli receives 1.08 m3/s of air from Sales, as
modeled in EnergyPlus (see above). Thus, for Sales, the return airflow rate is the supply airflow
rate minus 1.08 m3/s for all building vintages.
Table A21 Summary of HVAC system flow rates (m3/s) in Supermarket
Zone
Office
Dry Storage
Deli
Sales
Produce
Bakery
Restroom
New
Supply
0.58
3.06
2.17
9.69
3.20
2.14
N/A
Return
Post-1980
Supply Return
Pre-1980
Supply Return
0.53
2.73
1.83
7.60
2.88
1.83
N/A
1.05
5.63
2.39
16.05
5.74
2.33
N/A
1.13
6.03
2.33
16.56
6.07
2.28
N/A
1.00
5.16
2.05
13.33
5.17
2.02
N/A
1.08
5.56
1.99
13.78
5.46
1.97
N/A
Outside
Air
(m3/s)
0.05
0.47
0.34
3.49
1.07
0.31
0
Exhaust
air
(m3/s)
0
0
1.42
0
0
0.35
0.03
Schedules:
All HVAC and exhaust fans operate on the following schedule:
Everyday: on from 6:00 a.m. to 10:00 p.m., off otherwise
Outside air is supplied according to this schedule as well.
Occupants:
The peak number of people for each zone is listed in Table A20. Occupants in all building zones
are scheduled according to Figure A23. There is a different occupancy schedule for weekdays,
Saturdays, and Sundays/ holidays.
99
Occupancy Schedules
1
Weekday
0.9
Saturday
0.8
Sunday, Holiday
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A23 Occupancy schedule for Supermarket
A2.11. Small Hotel
Table A22 summarizes the zones modeled in CONTAM for the Small Hotel, their respective
sizes, and maximum occupancy.
Geometry:
1003 m2 footprint, four-story building with flat roof. Total floor area is 4014 m2. The EnergyPlus
model has 19 zones on the first floor and 16 zones on each of the upper floors (Figure A24). The
upper floor plans are identical. On the upper floors, there are five zones that represent three or
four hotel rooms lumped together. These are also modeled as single zones in the CONTAM
model. The Post-1980 and Pre-1980 buildings also have an attic that is 1.45 m high.
Large interior leakage paths were defined as follows:
Between Front Lounge and Corridor zones, a single large leakage path (50 % of the total
wall area between the spaces) is modeled;
Between Restroom and Corridor, a 0.186 m2 transfer grille is modeled.
100
Table A22 Summary of zones in Small Hotel
Zone
Floor
Area (m2)
Height (m)
Rear Stairs
Corridor
Rear Storage
Front Lounge
Restroom
Meeting Room
Mechanical Room
Guest 101
Guest 102
Guest 103
Guest 104
Guest 105
Employee Lounge
Laundry
Elevator
Exercise
Front Office
Front Stairs
Front Storage
Rear Stairs
Corridor
Rear Storage
Guest x01
Guest x02-5
Guest x06-8
Guest x09-12
Guest x13
Guest x14
Guest x15-18
Elevator
Guest x19
Guest x20-23
Guest x24
Front Storage
Front Stairs
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2-4
2-4
2-4
2-4
2-4
2-4
2-4
2-4
2-4
2-4
2-4
2-4
2-4
2-4
2-4
2-4
20
151
20
163
33
80
33
33
33
33
33
33
33
98
15
33
130
20
13
20
125
20
33
130
105
130
33
33
130
15
33
130
33
13
20
3.35
3.35
3.35
3.35
3.35
3.35
3.35
3.35
3.35
3.35
3.35
3.35
3.35
3.35
3.35
3.35
3.35
3.35
3.35
2.74
2.74
2.74
2.74
2.74
2.74
2.74
2.74
2.74
2.74
2.74
2.74
2.74
2.74
2.74
2.74
101
Maximum
occupancy
0
0
0
52.71
1.00
43.20
0
1.41
1.41
1.41
1.41
1.41
11
11
0
11
10.03
0
0
0
0
0
1.41
5.55
4.50
5.55
1.41
1.41
5.55
0
1.41
5.55
1.41
0
0
Rear stairs
Rear storage
2.44m
Rear stairs
Rear storage
Guest 104
Guest 103
3.96m
Guest 214
Guest 213
Guest 105
Guest 102
3.96m
Employee
lounge
Guest 101
Guest
215-218
Guest
209-212
Mech
3.96m
3.96m
Laundry
3.96m
Meeting
room
Elevator
Corridor
54.86m
3.96m
Guest 219
1.83m
Elevator
Corridor
3.05m
Exercise Room
Restroom
3.96m
Front Office
Front Lounge
11.89
m
Guest
206-208
Guest
220-223
3.96m
Guest 224
Guest
202-205
Front storage
1.52m
Front storage
Guest 201
Front Stairs
2.44m
Front Stairs
8.23 m
8.23 m
1.83 m 8.23 m
1.83 m 8.23 m
18.29 m
18.29 m
(a) Height 3.35 m
(b) Height 2.74 m
Figure A24 (a) First and (b) upper floor (2-4) plans of Small Hotel
HVAC systems:
For all building vintages, the EnergyPlus model has 12 packaged constant-volume single-zone
systems serving the common areas. Similarly, each zone (except the first floor Restroom) has a
constant-volume system in CONTAM. The constant-volume system for the Restroom in
EnergyPlus does not provide ventilation. Therefore, it is not modeled in CONTAM. The
Restroom exhaust depressurizes the zone. A transfer grille in the door facilitates air exchange
with the adjacent Corridor (see above). Thus, the exhaust flow rate for the Restroom was
modeled only in CONTAM, not in EnergyPlus.
102
The supply air, return air, outside air, and exhaust flow rates modeled in CONTAM are listed in
Table A23 for all three building vintages. In EnergyPlus, all of the guest rooms have individual
packaged-terminal air conditioning (PTAC) units that do not use an economizer. The PTAC are
modeled in CONTAM as local supply fans that inject the designated amount of outside air listed
in Table A24.
In EnergyPlus, the Front Stair, Rear Stair, Front Storage, and Rear Storage are heated using unit
heaters that recirculate air locally within the zones and do not impact whole-building airflow or
introduce outside air. Therefore, the unit heaters are not modeled in CONTAM.
In EnergyPlus, neutral building pressurization is modeled in all zones. To pressurize the building
in CONTAM, less air is returned than is supplied to each zone. In CONTAM, for the common
areas in Table A23, the building is pressurized by returning the larger of (a) 90 % of the supply
airflow or (b) the supply airflow minus the outside air requirement. The guest rooms in
Table A24 are pressurized by modeling an exhaust rate of 0.013 m3/s for each. For example,
Guest x02-05 is in reality four guest rooms, so that the exhaust rate is 0.013 4=0.05 m3/s.
Table A23 Summary of HVAC system flow rates (m3/s) in Small Hotel
Zone
Corridor
Corridor
Corridor
Corridor
Employee Lounge
Exercise
Front Lounge
Front Office
Laundry Room
Mechanical Room
Meeting Room
Restroom
Floor
1
2
3
4
1
1
1
1
1
1
1
1
New
Supply
0.49
0.23
0.21
0.34
0.31
0.12
0.73
0.32
1.54
0.05
0.43
N/A
Return
Post-1980
Supply Return
Pre-1980
Supply Return
0.45
0.21
0.19
0.31
0.28
0.11
0.66
0.29
1.40
0.05
0.39
N/A
0.55
0.30
0.28
0.31
0.33
0.14
0.82
0.43
1.57
0.05
0.47
N/A
0.57
0.32
0.30
0.36
0.34
0.14
0.90
0.45
1.58
0.07
0.50
N/A
0.51
0.27
0.25
0.28
0.30
0.13
0.74
0.39
1.43
0.05
0.43
N/A
0.53
0.29
0.27
0.33
0.30
0.13
0.81
0.41
1.43
0.06
0.45
N/A
Outside
Air
(m3/s)
0.04
0.03
0.03
0.03
0.09
0.11
0.42
0.10
0.14
0.01
0.43
0
Exhaust
air
(m3/s)
0
0
0
0
0
0
0
0
0
0
0
0.19
Schedules:
All HVAC and exhaust fans operate 24 hours per day every day of the year. Outside air is also
supplied all of the time.
Occupants:
The peak number of people for each zone is listed in Table A22. Occupants in all building zones
are scheduled according to Figure A25 to Figure A27. There are seven different occupant
schedules for the building. The occupancy schedules for the Restroom and Exercise zones are
shown in Figure A25. The occupancy schedule for the Lounges, Laundry, Meeting Room, and
Office is shown in Figure A26. The occupancy schedule for the guestrooms (referred to as
“Guest” occupancy) is shown in Figure A27. For some zones, there is a different occupancy
schedule for weekdays, Saturdays, and Sundays/ holidays.
103
Table A24 Summary of PTAC flow rates (m3/s) in Small Hotel
Zone
Floor
Guest 101
Guest 102
Guest 103
Guest 104
Guest 105
Guest x01
Guest x02-5
Guest x06-8
Guest x09-12
Guest x13
Guest x14
Guest x15-18
Guest x19
Guest x20-23
Guest x24
1
1
1
1
1
2-4
2-4
2-4
2-4
2-4
2-4
2-4
2-4
2-4
2-4
Outside
Air
(m3/s)
0.014
0.014
0.014
0.014
0.014
0.014
0.06
0.042
0.06
0.014
0.014
0.06
0.014
0.06
0.014
Restroom - WeekdayOccupancy Schedules
Restroom - Sunday, Holiday
Exhaust
air
(m3/s)
0.013
0.013
0.013
0.013
0.013
0.013
0.05
0.038
0.05
0.013
0.013
0.05
0.013
0.05
0.013
Restroom - Saturday
Exercise - Every day
1
0.9
0.8
Fraction
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A25 Occupancy schedules for Small Hotel (Restroom and Exercise)
104
Occupancy Schedules
1
Lounges - Weekday
0.9
Lounges - Weekend, Holiday
Laundry - Every day
0.8
Meeting Room - Every day
Fraction
0.7
Office - Weekday
Office - Weekend, Holiday
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A26 Occupancy schedules for Small Hotel
(Lounges, Laundry, Meeting Room, Office)
Occupancy Schedules
1
Guest - Weekday
0.9
Guest - Weekend, Holiday
0.8
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A27 Occupancy schedule for Small Hotel (Guest)
105
A2.12. Large Hotel
Table A25 summarizes the zones modeled in CONTAM for the Large Hotel, their respective
sizes, and maximum occupancy.
Table A25 Summary of zones in Large Hotel
Zone
Floor
Area (m2)
Height (m)
Basement
Stair NW
Elevator NW
Stair SE
Elevator SE
Retail 1
Retail 2
Mechanical Room
Storage
Laundry
Cafe
Lobby
Stair NW
Elevator NW
Stair SE
Elevator SE
Restroom
Room 1
Room 2
Room 3 (x19)
Room 4 (x19)
Room 5
Room 6
Corridor
Stair NW
Elevator NW
Stair SE
Elevator SE
Room 1
Room 2
Room 3 (x9)
Banquet
Dining
Kitchen
Corridor
Stair NW
Elevator NW
Stair SE
Elevator SE
Restroom
B
B
B
B
B
1
1
1
1
1
1
1
1
1
1
1
1
2-5
2-5
2-5
2-5
2-5
2-5
2-5
2-5
2-5
2-5
2-5
6
6
6
6
6
6
6
6
6
6
6
6
1919
20
19
11
10
67
78
164
95
78
189
1239
20
19
11
10
9
39
39
25
25
39
39
329
20
19
11
10
39
39
25
332
332
103
311
20
19
11
10
41
2.44
2.44
2.44
2.44
2.44
3.96
3.96
3.96
3.96
3.96
3.96
3.96
3.96
3.96
3.96
3.96
3.96
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
106
Maximum
occupancy
53.25
0
0
0
0
10.83
12.54
0.00
2.04
3.36
135.52
422.48
0
0
0
0
0
1.50
1.50
1.50
1.50
1.50
1.50
4.19
0
0
0
0
1.50
1.50
1.50
238.00
238.00
5.56
4.44
0
0
0
0
0
Geometry:
1979 m2 footprint, six-story building (plus a basement) with flat roof. Total floor area is
11 345 m2 which includes the Basement. The EnergyPlus model has seven zones on the first
floor, 43 zones each on floors two to five, and 12 zones on the sixth floor. The upper floors
(floors two to five) have identical floor plans. On the upper floors, there are zones that represent
several rooms lumped together (Room 3 and Room 4 in Figure A28b, and Room 3 in
Figure A28c). These are also modeled as single zones in CONTAM.
In CONTAM, the following zones are added (shaded in Figure A28):
A 3.05 m 3.05 m Restroom is added on the first floor between the Laundry and Storage
zones, carved out of the Lobby;
A 3.66 m 11.28 m Restroom is added on the sixth floor across from the Dining zone,
carved out of the Corridor;
A Stairwell and Elevator Shaft are added near the northwest corner of the building, carved
out of the Lobby or Corridor. The Stairwell is 3 m 6.71 m, and the Elevator Shaft is
2.79 m 6.71 m;
A Stairwell and Elevator Shaft are added near the southeast corner of the building, carved
out of the Lobby or Corridor. The Stairwell is 3 m 3.66 m and the Elevator Shaft is
2.79 m 3.66 m.
Large interior leakage paths were defined as follows:
Between Retail 1 and Lobby on the first floor, and between Retail 2 and Lobby, zones,
a single large leakage path of 4 m2 is modeled;
Between Café and Lobby zones on the first floor, a single large leakage path of 8 m2
is modeled;
Between Laundry and Restroom zones on the first floor, a single large leakage path of 4 m2
is modeled;
Between Laundry and Lobby zones on the first floor, and between Restroom and Lobby
zones on the first floor, a 0.186 m2 transfer grille is modeled;
Between Restroom and Corridor zones on the sixth floor, two 0.186 m2 transfer grilles
are modeled;
Between Kitchen and Dining zones on the sixth floor, a single large leakage path that
is 50 % of the total wall area between the spaces is modeled.
A stairwell is defined using CONTAM’s stair shaft model for closed treads and zero
people;
An elevator shaft is defined using CONTAM’s elevator shaft model.
107
86.56 m
11.58 m
42.37 m
15.85 m
9.14m 3.05m 4.57m
NW
Stair/
elev
10.36m
Stor
Mech
Lobby
6.71m
Lobby
Retail 2
Retail 1
5.79m
4.57m
8.53m
SE
Stair/
elev
L
a
u
n
dr
y
22.86m
Cafe
(a) First floor (height 3.96 m)
5.79m
69.50 m total (19 rooms at 3.66 m each)
NW
Room Stair/
2
elev
Room 4 (repeated 19 times)
6.71m
Room 3 (repeated 19 times)
Room
1
4.57m 2.13m
2.13m 4.57m
3.66m
Corridor
8.53m
R
R
Corridor
SE
Stair/
elev
6.70m
69.50 m total (19 rooms at 3.66 m each)
R
o
o
m
6
R
o
o
m
5
8.53m
8.53m
5.79m 4.57m
(b) Second to fifth floors (height 3.05 m)
4.57m
8.53m
5.79m
32.00 m
NW
Room Stair/
2
elev
5.18m
Banquet
32.00 m
7.01 m
10.36m
Dining
Kitchen
3.052m Room
1
3.66m
4.57m
Corridor
Corridor
RR
Room 3 (repeated 9 times)
60.35 m total (9 rooms at 6.71 m each)
6.71m
SE
Stair/
elev
17.07 m
4.57m
(c) Sixth floor (height 3.05 m)
Figure A28 (a) First, (b) second to fifth, and (c) sixth floors plans of Large Hotel
108
HVAC systems:
For the New and Post-1980 buildings, the EnergyPlus model has one VAV system serving the
common areas, including the Basement. The design supply flow rate calculated by EnergyPlus
for each VAV system is used as the supply flow rate for the constant-volume system modeled in
CONTAM for simplicity. The system modeled in CONTAM is still referred to as a “VAV”
system in the body of this text. Varying the supply flow rate can be implemented in CONTAM
using controls and/or schedules by users who wish to do so. The supply air, return air, outside air,
and exhaust flow rates modeled in CONTAM are listed in Table A26 for the New and Post-1980
buildings. For the Pre-1980 buildings, the building has one CAV system serving the common
areas including the Basement. Similarly, a constant-volume system is modeled in CONTAM.
The supply air, return air, outside air, and exhaust flow rates modeled in CONTAM are listed in
Table A27 for the Pre-1980 building. The exhaust flow rates for the Restrooms were modeled
only in CONTAM, not in EnergyPlus.
In EnergyPlus, there was also a Dining exhaust fan (1.84 m3/s) in addition to the Kitchen exhaust
fan (0.04 m3/s) and Laundry exhaust fan (0.24 m3/s). The Dining exhaust fan was included in
order to transfer air from the Dining zone to the Kitchen. This is modeled in CONTAM using a
large opening between the Dining and Kitchen zones (see above), and one larger exhaust fan in
the Kitchen (1.88 m3/s). The sum of the Dining and Kitchen exhaust rates in EnergyPlus is
1.88 m3/s.
For all building vintages, the EnergyPlus model has two dedicated outdoor air systems
(DOAS) – one serves the guestrooms on the first floor and the other serves the guestrooms on
floor two through five. Both systems deliver 100 % outside air. Similarly, two constant-volume
systems are modeled in CONTAM. The outside air (also the supply air) and exhaust flow rates
modeled in CONTAM are listed in Table A28. No air is returned to the DOAS in CONTAM.
In EnergyPlus, fan coil units in each guest room provide temperature control. They recirculate air
locally within the zone and do not impact whole-building airflow or introduce outside air. In
EnergyPlus, the sixth floor Corridor has a unit heater that recirculates air locally within the zone
and does not impact whole-building airflow or introduce outside air. The fan coils and unit heater
are not modeled in CONTAM.
In EnergyPlus, neutral building pressurization is modeled in all zones. To pressurize the
building in CONTAM, less air is returned than is supplied to each zone. For all building vintages,
in the common areas (Table A26 and Table A27), the return airflow rate is set to 90 % of the
supply airflow rate. The return airflow from the Dining zone is reduced by the Kitchen exhaust
(1.88 m3/s) for all building vintages. For all building vintages, in the guestrooms (Table A28),
the exhaust flow rates are 90 % of the outside air (or supply air) flow rates. The exhaust flow
rates for the guestrooms were modeled only in CONTAM, not in EnergyPlus.
109
Table A26 Summary of VAV system flow rates (m3/s) in Large Hotel for
New and Post-1980 buildings
Zone
Floor
New
Supply
Return
Post-1980
Supply
Return
Basement
B
4.25
3.83
4.62
Retail 1
1
0.51
0.46
0.70
Retail 2
1
0.59
0.54
0.80
Mechanical Room
1
0.10
0.09
0.04
Storage
1
0.07
0.07
0.07
Laundry
1
5.54
4.75
5.61
Cafe
1
2.04
1.84
2.27
Lobby
1
9.24
8.28
10.40
Restroom
1
N/A
N/A
N/A
Corridor
2-5
0.10
0.09
0.34
Banquet
6
4.21
3.79
4.81
Dining
6
4.34
2.07
4.93
Kitchen
6
1.99
1.75
2.04
Corridor
6
0.42
0.17
0.45
Restroom
6
N/A
N/A
N/A
Total VAV
33.72
27.98
38.08
Note: Exhaust air rates are the same for all building vintages.
4.16
0.63
0.72
0.04
0.07
4.81
2.04
9.33
N/A
0.30
4.33
2.60
1.80
0.19
N/A
31.91
Outside
Air
(m3/s)
1.48
0.20
0.23
0.03
0.02
1.86
0.72
3.27
0
0.07
1.50
1.54
0.67
0.14
0
11.94
Exhaust
air
(m3/s)
0
0
0
0
0
0.24
0
0
0.04
0
0
0
1.88
0
0.21
Table A27 Summary of CAV system flow rates (m3/s) in Large Hotel for Pre-1980 buildings
Zone
Floor
Pre-1980
Supply
Return
Basement
Retail 1
Retail 2
Mechanical Room
Storage
Laundry
Cafe
Lobby
Corridor
Banquet
Dining
Kitchen
Corridor
Total CAV
B
1
1
1
1
1
1
1
2-5
6
6
6
6
3.80
0.69
0.80
0.06
0.07
5.58
2.44
10.28
0.34
4.72
4.84
2.01
0.54
37.19
3.42
0.62
0.72
0.06
0.07
4.78
2.20
9.22
0.31
4.25
2.52
1.77
0.28
31.11
Outside
Air
(m3/s)
1.221
0.22
0.26
0.02
0.02
1.79
0.78
3.30
0.111
1.52
1.55
0.65
0.17
11.94
Note 1: Compared with the outside air requirements for the New and Post-1980 buildings, the largest differences are
for the Basement and Corridor zones in the Pre-1980 buildings.
110
Table A28 Summary of DOAS flow rates (m3/s) in Large Hotel for all building vintages
Zone
Floor
Room 1
Room 2
Room 3 (x19)
Room 4 (x19)
Room 5
Room 6
DOAS 1
Room 1
Room 2
Room 3 (x9)
DOAS 2
2-5
2-5
2-5
2-5
2-5
2-5
6
6
6
Outside
Air
(m3/s)
0.014
0.014
0.27
0.27
0.014
0.014
2.35
0.014
0.014
0.13
0.15
Exhaust
air
(m3/s)
0.013
0.013
0.24
0.24
0.013
0.013
0.013
0.013
0.11
Schedules:
The DOAS and exhaust fans operate 24 hours per day every day of the year. Outside air is also
supplied all of the time. The VAV and CAV fans operate on the following schedule:
Every day: on from 7:00 a.m. to 12:00 a.m., off otherwise
Outside air is supplied according to this schedule as well for the VAV and CAV systems.
Occupants:
The peak number of people for each zone is listed in Table A25. Occupants in all building zones
are scheduled according to Figure A29 to Figure A30. There are three different occupant
schedules for the building. The occupancy schedules for the guestrooms (referred to as
“Guest” occupancy) and Lobby zone are shown in Figure A29. The occupancy schedule for the
remaining zones is shown in Figure A30. For some zones, there is a different occupancy
schedule for weekdays, Saturdays, and Sundays/ holidays.
111
Occupancy Schedules
1
Lobby - Weekday
0.9
Lobby - Weekend, Holiday
Guest - Weekday
0.8
Guest - Weekend, Holiday
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A29 Occupancy schedules for Large Hotel (Lobby, Guest)
Occupancy Schedules
1
Building - Weekday
0.9
Building - Saturday
Building - Sunday, Holiday
0.8
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A30 Occupancy schedule for Large Hotel (Building)
112
A2.13. Hospital
Table A29 summarizes the zones modeled in CONTAM for the Hospital, their respective sizes,
and maximum occupancy. The table also lists the occupancy schedule for each zone
(details given below on schedule type).
Geometry:
3739 m2 footprint, five-story building (plus a basement) with flat roof. Total floor area is
22 436 m2 which includes the Basement. The EnergyPlus model has nine zones on the first floor,
11 zones on second, 13 zones on third and fourth floors, and eight zones on the fifth floor
(Figure A31 to Figure A34). The third and fourth floors have identical floor plans.
In CONTAM, the following zones are added (shaded in Figure A31 to Figure A34):
A 4.57 m 7.62 m Restroom is added on the first floor between the Office 1 and Corridor
zones, carved out of the Lobby;
A 6.10 m 9.14 m Restroom is added on the second floor, carved out of the OR Nurse
Station;
A 6.10 m 9.14 m Restroom is added on the third and fourth floors, carved out of the
Nurse Station Lobby;
A 4.57 m 12.19 m Restroom is added on the sixth floor, carved out of the Nurse Station;
A Stairwell and Elevator Shaft are added near the north and south sides the building,
carved out of the Basement, Corridor, or Nurse Station on the sixth floor. Both the
Stairwell and Elevator Shaft are 4.46 m 5.39 m
There are patient rooms, exam rooms, operating rooms, and offices that are modeled in
EnergyPlus using “multipliers”. These are modeled as single zones in CONTAM, except for
three sets where the multiplied zones were not adjacent to one another. These are modeled as
follows:
On the first floor, ER Exam 3 is multiplied by a factor of four in the EnergyPlus model,
with two times on each side of the building. It is modeled in CONTAM as two zones
(ERExam3 2a and ERExam3 2b – indicating that two rooms are grouped into a zone at
each location);
On the third and fourth floors, Patient Room 1 is multiplied by a factor of 10, with five on
each side of the building. It is modeled in CONTAM as two zones (PatRm1a 5 and
PatRm1b 5 – indicating that five rooms are grouped into a zone at each location);
On the third and fourth floors, Patient Room 5 is multiplied by a factor of 10 in the
EnergyPlus model, with five on each side of the building. It is modeled in CONTAM as
two zones (PatRm5a 5 and PatRm5b 5 – indicating that five rooms are grouped into a
zone at each location).
Large interior leakage paths were defined as follows:
Between Lobby and Corridor zones on the first floor, a single large leakage path that is
50 % of the total wall area between the spaces is modeled;
Between ER Nurse Station and Corridor zones on the first floor, a single large leakage path
of 8 m2 is modeled;
113
Table A29 Summary of zones in Hospital
Zone
Floor
Area
(m2)
Height
(m)
Maximum
occupancy
Basement
ER_Exam1_Mult4
ER_Trauma1
ER_Exam3_Mult4
ER_Trauma2
ER_Triage_Mult4
Office1_Mult4
Lobby_Records
Corridor
ER_NurseStn_Lobby
OR1
OR2_Mult5
OR3
OR4
IC_PatRoom1_Mult5
IC_PatRoom2
IC_PatRoom3_Mult6
ICU
ICU_NurseStnLobby
Corridor
OR_NurseStn_Lobby
PatRoom1_Mult10
PatRoom2
PatRoom3_Mult10
PatRoom4
PatRoom5_Mult10
PhysTherapy
PatRoom6
PatRoom7_Mult10
PatRoom8
NurseStn_Lobby
Lab
Corridor_SE
Corridor_NW
PatRoom1_Mult10
PatRoom2
PatRoom3_Mult10
PatRoom4
PatRoom5_Mult10
Radiology
PatRoom6
PatRoom7_Mult10
PatRoom8
NurseStn_Lobby
Lab
B
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
4
3643
28
28
28
28
28
14
1440
473
1236
56
56
56
223
21
28
21
618
669
473
957
21
35
20
35
21
488
28
20
28
850
265
518
518
21
35
20
35
21
488
28
20
28
850
265
2.44
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
100.6
6.00
6.00
6.00
6.00
6.00
1.05
21.09
6.15
17.67
3.00
3.00
3.00
12.00
1.12
1.50
1.12
33.25
9.56
6.15
14.48
1.12
1.88
1.09
1.88
1.12
26.25
1.50
1.09
1.50
12.95
14.25
6.12
6.12
1.12
1.88
1.09
1.88
1.12
26.25
1.50
1.09
1.50
12.95
14.25
114
Occupancy schedule
(see below for
details)
Admin
Critical
Critical
Critical
Critical
Critical
Admin
Admin
Admin
Admin
Critical
Critical
Critical
Critical
Critical
Critical
Critical
Critical
Admin
Admin
Admin
Critical
Critical
Critical
Critical
Critical
Admin
Critical
Critical
Critical
Admin
Admin
Admin
Admin
Critical
Critical
Critical
Critical
Critical
Admin
Critical
Critical
Critical
Admin
Admin
Zone
Floor
Area
(m2)
Height
(m)
Maximum
occupancy
Corridor_SE
Corridor_NW
Dining
NurseStn_Lobby
Kitchen
Office1
Office2_Mult5
Office3
Office4_Mult6
Corridor
Restroom
Restroom
Restroom
Restroom
Restroom
Stair 1
Stair 2
Elev 1
Elev2
4
4
5
5
5
5
5
5
5
5
1
2
3
4
5
all
all
all
all
518
518
641
993
929
70
70
70
14
454
35
56
56
56
56
24
24
24
24
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
4.27
6.12
6.12
75.00
14.88
50.00
5.25
5.25
5.25
1.05
5.42
0
0
0
0
0
0
0
0
0
Occupancy schedule
(see below for
details)
Admin
Admin
Admin
Admin
Admin
Admin
Admin
Admin
Admin
Admin
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Between ICU Nurse Station and OR Nurse Station zones on the second floor, a single large
leakage path of 8 m2 is modeled;
Between Nurse Station Lobby and Corridors zones on the fifth floor, two large leakage
paths of 4 m2 are modeled;
Between Nurse Station Lobby and Dining zones on the sixth floor, one single large leakage
path of 4 m2 is modeled;
All Restrooms are modeled with a 0.186 m2 transfer grille in the door between the zone
and adjacent zone (Corridor for floors one to four, Dining for sixth floor).
A stairwell is defined using CONTAM’s stair shaft model for closed treads and zero
people;
An elevator shaft is defined using CONTAM’s elevator shaft model.
115
Stair/Elev 2
116
Figure A31 First floor plan of Hospital (height 4.27 m), all dimensions in meters
Restroom
Stair/Elev 1
Restroom
117
Figure A32 Second floor plan of Hospital (height 4.27 m), all dimensions in meters
Stair/Elev 2
Stair/Elev 1
6.1
Restroom
118
Figure A33 Third/Fourth floor plans of Hospital (height 4.27 m), all dimensions in meters
Stair/Elev 2
Stair/Elev 1
Restroom
12.39
119
Figure A34 Fifth floor plans of Hospital (height 4.27 m), all dimensions in meters
Stair/Elev 2
Stair/Elev 1
4.52
HVAC systems:
For all building vintages, the EnergyPlus model has two VAV systems and two CAV systems.
The two VAV systems serve the “administrative” zones, and the two CAV systems serve the
“critical” zones. The design supply flow rate calculated by EnergyPlus for each VAV system is
used as the supply flow rate for the constant-volume system modeled in CONTAM for simplicity.
The system modeled in CONTAM is still referred to as a “VAV” system in the body of this text.
Varying the supply flow rate can be implemented in CONTAM using controls and/or schedules
by users who wish to do so. The supply air, return air, outside air, and exhaust flow rates
modeled in CONTAM are listed in Table A30 for both the VAV and CAV systems. In
EnergyPlus, each HVAC system is assigned a minimum ventilation requirement and is modeled
as such in CONTAM. For CAV 1, the minimum ventilation requirement is 4.16 m3/s, it is
2.54 m3/s for CAV 2, it is 5.18 m3/s for VAV 1, and it is 9.49 m3/s for VAV 2 for all building
vintages. The exhaust flow rates for the Restrooms were modeled only in CONTAM, not in
EnergyPlus.
In EnergyPlus, there was also a Dining exhaust fan (0.75 m3/s) in addition to the Kitchen exhaust
fan (1.75 m3/s). The Dining exhaust fan was included in order to transfer air from the Dining
zone to the Kitchen. This is modeled in CONTAM using a large opening between the Dining and
Kitchen zones (see above), and one larger exhaust fan in the Kitchen (2.5 m3/s). The sum of the
Dining and Kitchen exhaust rates in EnergyPlus is 2.5 m3/s.
In EnergyPlus, neutral building pressurization is modeled in all zones. To pressurize the building
in CONTAM, less air is returned than is supplied to each zone. For all building vintages, the
return airflow rate is set to 90 % of the supply airflow rate. The return airflow from the Kitchen
is reduced by 1.75 m3/s, and the return airflow from the Dining is reduced by 0.75 m3/s, to allow
makeup air for the Kitchen exhaust (2.5 m3/s).
Schedules:
All the HVAC system and exhaust fans operate 24 hours per day every day of the year. Outside
air is also supplied all of the time.
Occupants:
The peak number of people for each zone is listed in Table A29. Occupants in all building zones
are scheduled according to Figure A35. There are two different occupant schedules for the
building. The occupancy schedule for the critical is for exam rooms, trauma rooms, triage,
operating rooms, and patient rooms. The “Admin” occupancy schedule is for the remaining
zones.
120
Table A30 Summary of VAV and CAV system flow rates (m3/s) in Hospital
Zone
Floor
New
Supply Return
Post-1980
Pre-1980
Supply Return Supply Return
ER_Exam1_Mult4
ER_Exam3_Mult4
ER_Trauma1
ER_Trauma2
ER_Triage_Mult4
IC_PatRoom1_Mult5
PatRoom1_Mult10
PatRoom5_Mult10
PatRoom7_Mult10
PatRoom3_Mult10
PatRoom5_Mult10
PatRoom6
PatRoom7_Mult10
CAV 1 Total
IC_PatRoom2
OR1
OR2_Mult5
OR3
OR4
PatRoom2
PatRoom6
PatRoom8
PatRoom4
CAV 2 Total
Basement
Corridor
ER_NurseStn_Lobby
Lobby_Records
Office1_Mult4
Corridor
IC_PatRoom3_Mult6
ICU_NurseStn_Lobby
OR_NurseStn_Lobby
Lab
PatRoom3_Mult10
PatRoom1_Mult10
PatRoom8
VAV 1 Total
ICU
Corridor_NW
Corridor_SE
NurseStn_Lobby
PatRoom4
PhysTherapy
Corridor_NW
1
1
1
1
1
2
3
3
3
4
4
4
4
1.59
1.59
0.40
0.40
1.59
0.74
1.49
1.49
1.67
1.44
1.49
0.23
1.66
15.76
0.25
0.99
4.96
0.99
3.97
0.25
0.23
0.22
0.25
12.10
4.18
0.84
3.62
3.74
0.25
1.35
1.16
2.19
2.64
1.88
1.44
1.49
0.22
25.00
4.40
1.34
1.34
2.20
0.25
3.47
1.34
1.59
1.59
0.40
0.40
1.59
0.86
1.49
1.49
2.03
1.60
1.49
0.29
2.02
16.83
0.34
1.36
6.66
1.33
5.00
0.28
0.29
0.28
0.26
15.81
5.64
0.96
4.10
3.96
0.34
1.35
1.55
2.46
2.97
1.88
1.61
1.49
0.28
28.60
4.63
1.34
1.34
2.43
0.26
3.47
1.34
2
2
2
2
2
3
3
3
4
B
1
1
1
1
2
2
2
2
3
3
4
4
2
3
3
3
3
3
4
1.43
1.43
0.36
0.36
1.43
0.67
1.34
1.34
1.50
1.29
1.34
0.21
1.50
14.18
0.22
0.89
4.46
0.89
3.57
0.22
0.21
0.20
0.22
10.89
3.76
0.76
3.25
3.37
0.23
1.21
1.05
1.97
2.38
1.69
1.29
1.34
0.20
22.50
3.96
1.21
1.21
1.98
0.22
3.12
1.21
121
1.43
1.43
0.36
0.36
1.43
0.77
1.34
1.34
1.83
1.44
1.34
0.26
1.82
15.15
0.31
1.22
5.99
1.20
4.50
0.25
0.26
0.25
0.24
14.23
5.08
0.87
3.69
3.56
0.31
1.22
1.40
2.21
2.67
1.69
1.45
1.34
0.25
25.74
4.17
1.21
1.21
2.19
0.24
3.12
1.21
1.59
1.59
0.40
0.40
1.59
0.87
1.49
1.49
2.14
1.68
1.49
0.31
2.13
17.16
0.36
1.37
6.69
1.33
5.00
0.30
0.31
0.30
0.27
15.92
5.39
1.01
4.13
4.15
0.37
1.35
1.62
2.46
3.03
1.88
1.68
1.49
0.29
28.85
4.71
1.34
1.34
2.43
0.28
3.47
1.34
1.43
1.43
0.36
0.36
1.43
0.79
1.34
1.34
1.93
1.51
1.34
0.28
1.92
15.45
0.32
1.23
6.02
1.20
4.50
0.27
0.28
0.27
0.25
14.33
4.85
0.91
3.72
3.74
0.33
1.22
1.46
2.21
2.73
1.69
1.51
1.34
0.27
25.97
4.24
1.21
1.21
2.19
0.25
3.12
1.21
Outside Exhaust
Air
air
(m3/s)
(m3/s)
0
0
0
0
0
0
0
0
0
0
0
0
0
4.16
0
0
0
0
0
0
0
0
0
2.54
0
0
0
0
0
0
0
0
0
0
0
0
0
5.18
0
0
0
0
0
0
0
Zone
Corridor_SE
Lab
NurseStn_Lobby
PatRoom2
Radiology
Corridor
Dining
Kitchen
NurseStn_Lobby
Office1
Office2_Mult5
Office3
Office4_Mult6
VAV 2 Total
Floor
4
4
4
4
4
5
5
5
5
5
5
5
5
New
1.34
1.88
2.25
0.25
8.67
1.12
2.76
3.26
3.23
0.49
2.14
0.47
0.38
42.58
1.21
1.69
2.02
0.22
7.81
1.01
1.73
1.18
2.90
0.44
1.92
0.43
0.35
35.82
Post-1980
1.34
1.21
1.88
1.69
2.48
2.23
0.28
0.25
8.67
7.80
1.22
1.10
3.62
2.51
3.31
1.23
3.32
2.99
0.58
0.53
2.52
2.27
0.57
0.51
0.50
0.45
45.11
38.10
Pre-1980
1.34
1.21
1.88
1.69
2.48
2.23
0.30
0.27
8.67
7.80
1.37
1.23
3.97
2.82
3.26
1.18
3.73
3.36
0.64
0.58
2.75
2.48
0.62
0.56
0.56
0.50
46.47
39.32
Outside Exhaust
Air
air
0
3
3
(m /s)
(m
0 /s)
0
0
0
0
0
2.5
0
0
0
0
0
9.49
Admin Occupancy Schedules
1
Admin - Weekday
0.9
Admin - Saturday
Admin - Sunday, Holiday
0.8
Critical - Every day
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A35 Occupancy schedules for Hospital
122
A2.14. Outpatient Health Care
Table A31 summarizes the zones modeled in CONTAM for the Outpatient Health Care, their
respective sizes, and maximum occupancy.
Table A31 Summary of zones in Outpatient Health Care
Zone
Floor
Anesthesia
Bio Hazard
Café
Clean
Clean Work
Dictation
Dressing Room
Electrical Room
Elevator Pump Room
Humid
IT Hall
IT Room
Lobby
Lobby Hall
Lobby Toilet
Locker Room
Locker Room Hall
Lounge
Med Gas
MRI Control Room
MRI Hall
MRI Room
MRI Toilet
Nourishment
Nurse Hall
Nurse Janitor
Nurse Station
Nurse Toilet
Office
Operating Room 1
Operating Room 2
Operating Room 3
PACU
Pre-Op Hall
Pre-Op Room 1
Pre-Op Room 2
Pre-Op Toilet
Procedure Room
Reception
Reception Hall
Recovery Room
Scheduling
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
123
Area
(m2)
10
5
39
12
15
12
4
9
8
5
13
10
58
22
5
61
46
33
5
16
14
41
5
17
46
5
24
5
45
43
45
44
10
49
18
31
5
26
47
12
50
11
Height
(m)
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
Maximum
occupancy
0.00
0.00
39.02
2.34
3.07
0.59
0.21
0.00
0.00
0.25
0.00
0.52
17.34
0.00
0.00
9.20
0.00
5.02
0.00
3.12
0.00
8.18
0.00
3.38
0.00
0.00
4.85
0.00
2.24
8.55
8.92
8.84
2.01
0.00
1.76
3.14
0.00
5.30
14.19
0.00
10.03
0.55
Zone
Floor
Scrub
Soil
Soil Hold
Soil Work
Step Down
Sterile Hall
Sterile Storage
Storage
Sub-Sterile
Utility Hall
Utility Janitor
Utility Room
Vestibule
Conference
Conference Toilet
Dictation
Exam 1
Exam 2
Exam 3
Exam 4
Exam 5
Exam 6
Exam 7
Exam 8
Exam 9
Exam Hall 1
Exam Hall 2
Exam Hall 3
Exam Hall 4
Exam Hall 5
Exam Hall 6
Janitor
Lounge
Nurse Station 1
Nurse Station 2
Office
Office Hall
Reception
Reception Hall
Reception Toilet
Scheduling 1
Scheduling 2
Storage 1
Storage 2
Storage 3
Utility
Work
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
124
Area
(m2)
8
12
5
17
28
57
37
85
18
24
4
33
7
31
6
7
33
50
67
8
33
21
74
25
37
17
17
17
18
18
18
6
7
14
17
52
41
91
52
12
30
32
5
11
13
12
157
Height
(m)
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
Maximum
occupancy
0.00
2.34
1.04
3.34
5.57
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
15.61
0.00
0.33
6.69
10.03
13.38
1.56
6.50
4.18
14.72
5.02
7.36
0.00
0.00
0.00
0.00
0.00
0.00
0.00
1.11
2.79
3.34
2.60
0.00
27.42
0.00
0.00
1.51
1.59
0.00
0.00
0.00
0.00
7.85
Zone
Floor
Work Hall
Work Toilet
X-Ray
Dressing Room
Elevator Hall
Humid
Janitor
Locker
Lounge
Lounge Toilet
Mechanical
Mechanical Hall
Office
Office Hall
Office Toilet
Physical Therapy 1
Physical Therapy 2
Physical Therapy Toilet
Storage 1
Storage 2
Treatment
Undeveloped 1
Undeveloped 2
Utility
Work
NE Stair
NW Elevator
NW Stair
SW Stair
2
2
2
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
all
all
all
all
Area
(m2)
77
5
84
4
34
10
6
11
71
18
33
28
282
77
5
121
55
8
10
8
44
211
107
20
53
16
13
18
9
Height
(m)
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
9.14
9.14
9.14
9.14
Maximum
occupancy
0.00
0.00
16.72
0.20
0.00
0.50
0.00
1.67
10.58
0.00
0.00
0.00
14.10
0.00
0.00
24.15
11.00
0.00
0.00
0.00
8.84
0.00
0.00
0.00
2.67
0.00
0.00
0.00
0.00
Geometry:
1373 m2 footprint, three-story building with flat roof. The second and third floors have a slightly
smaller footprint of 1232 m2 each. Total floor area is 3837 m2. The EnergyPlus model has
55 zones on the first floor, 37 zones on second floor, and 22 zones the third floor. Three
Stairwells and one Elevator Shaft are modeled in EnergyPlus as single tall zones with heights
equal to the height of the building. In CONTAM, they are modeled as one zone per floor, with
large leakage paths connecting them (see below).
Large interior leakage paths were defined as follows:
All rooms with exhaust fans (see Table A31) are modeled with a 0.186 m2 transfer grille in
the door between the zone and adjacent zone. The exception is the MRI room which does
not have a transfer grille modeled.
Between the following zones a single large leakage path of 4 m2 is modeled:
First floor: Between Lobby Hall and Lobby
First floor: Between Lobby Hall and Reception
First floor: Between Reception Hall and Pre-Op Hall
125
First floor: Between Nurse Station and Nurse Hall
First floor: Between Locker Room Hall and Pre-Op Hall
First floor: Between Nurse Hall and Pre-Op Hall
Second floor: Between Reception and Work Hall
Second floor: Between Reception and Reception Hall
Second floor: Between Office Hall and Work Hall
Third floor: Between Elevator Hall and Office Hall
Third floor: Between Mechanical Hall and Office Hall
A stairwell is defined using CONTAM’s stair shaft model for closed treads and zero
people;
An elevator shaft is defined using CONTAM’s elevator shaft model.
126
127
Figure A36 First floor plan of Outpatient Health Care, all dimensions in meters
128
Figure A37 Second floor plan of Outpatient Health Care, all dimensions in meters
129
Figure A38 Third floor plan of Outpatient Health Care, all dimensions in meters
HVAC systems:
For all building vintages, the EnergyPlus model has two VAV (referred to as “AHU” systems
here and in the models). One serves the first floor and the other serves the second and third floors.
The design supply flow rate calculated by EnergyPlus for each VAV system is used as the supply
flow rate for the constant-volume system modeled in CONTAM for simplicity. The system
modeled in CONTAM is still referred to as a “VAV” system in the body of this text. Varying the
supply flow rate can be implemented in CONTAM using controls and/or schedules by users who
wish to do so. The supply air, return air, outside air, and exhaust flow rates modeled in
CONTAM are listed in Table A32. In EnergyPlus, each HVAC system is assigned a minimum
ventilation requirement and is modeled as such in CONTAM. For AHU 1, the minimum
ventilation requirement is 1.82 m3/s and 1.90 m3/s for AHU 2 for all building vintages.
All of the exhaust flow rates (except for the “Toilet” zones) are modeled in EnergyPlus and
CONTAM. The exhaust flow rates for the “Toilet” zones were modeled only in CONTAM, not
in EnergyPlus. In CONTAM, the exhaust fans are modeled either as direct (on an exterior wall)
exhaust fans or using ducts, depending on whether the room has an exterior wall.
The EnergyPlus model specifies a constant rate of air exchange between several zones that have
no local exhaust. These zones also have no mechanical supply air. Thus, this is a method to drive
air movement in the building. In CONTAM, this is done by pressurizing the building and
allowing some transfer air to occur through natural driving forces and transfer grilles.
In EnergyPlus, neutral building pressurization is modeled in all zones. To pressurize the building
in CONTAM, less air is returned than is supplied to each zone. For all building vintages, the
return airflow rate is set to 90 % of the supply airflow rate. In CONTAM, only the MRI Room is
neutrally pressurized. The return airflow rate is the supply airflow rate minus the exhaust rate for
all building vintages.
Schedules:
The AHU 1 and first floor exhaust fans operate on the following schedule:
Weekdays: 4:00 a.m. to 9:00 p.m., off otherwise
Saturdays: 4:00 a.m. to 9:00 p.m., off otherwise
Sundays and holidays: off all day
Outside air for AHU 1 is supplied according to this schedule as well.
The AHU 2 and second and third floor exhaust fans operate on the following schedule:
Weekdays: 6:00 a.m. to 6:00 p.m., off otherwise
Saturdays: 6:00 a.m. to 6:00 p.m., off otherwise
Sundays and holidays: off all day
Outside air for AHU 2 is supplied according to this schedule as well.
Occupants:
The peak number of people for each zone is listed in Table A31. Occupants in all building zones
are scheduled according to Figure A39. There is a different occupancy schedule for weekdays,
Saturdays, and Sundays/ holidays.
130
Table A32 Summary of VAV system flow rates (m3/s) in Outpatient Healthcare
Zone
Anesthesia
Bio Hazard
Café
Clean
Clean Work
Dictation
Dressing Room
Electrical Room
Elevator Pump Room
Humid
IT Hall
IT Room
Lobby
Lobby Hall
Lobby Toilet
Locker Room
Locker Room Hall
Lounge
Med Gas
MRI Control Room
MRI Hall
MRI Room
MRI Toilet
Nourishment
Nurse Hall
Nurse Janitor
Nurse Station
Nurse Toilet
Office
Operating Room 1
Operating Room 2
Operating Room 3
PACU
Pre-Op Hall
Pre-Op Room 1
Pre-Op Room 2
Pre-Op Toilet
Procedure Room
Reception
Reception Hall
Recovery Room
Scheduling
Scrub
Soil
Soil Hold
Floor New
Supply
Return
Post-1980
Supply Return
Pre-1980
Supply Return
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0.07
0.005
0.39
0.05
0.07
0.03
0.04
N/A
N/A
0.01
0.02
0.03
0.47
0.03
N/A
0.32
0.06
0.16
0.05
0.07
0.02
2.18
N/A
0.08
0.06
N/A
0.11
N/A
0.11
1.00
1.06
0.87
0.06
0.06
0.08
0.14
N/A
0.30
0.23
0.02
0.34
0.04
0.011
0.09
0.04
0.08
0.006
0.46
0.06
0.08
0.04
0.07
N/A
N/A
0.02
0.02
0.04
0.53
0.03
N/A
0.38
0.06
0.18
0.09
0.10
0.02
2.45
N/A
0.10
0.06
N/A
0.14
N/A
0.15
1.45
1.47
1.25
0.07
0.06
0.09
0.16
N/A
0.34
0.25
0.02
0.48
0.06
0.010
0.10
0.04
0.09
0.006
0.49
0.06
0.08
0.04
0.08
N/A
N/A
0.02
0.02
0.04
0.59
0.03
N/A
0.39
0.06
0.18
0.11
0.10
0.02
2.45
N/A
0.10
0.06
N/A
0.14
N/A
0.15
1.51
1.53
1.25
0.07
0.06
0.10
0.16
N/A
0.34
0.27
0.02
0.53
0.06
0.010
0.10
0.04
0.08
0.005
0.43
0.06
0.08
0.03
0.04
N/A
N/A
0.02
0.02
0.03
0.53
0.03
N/A
0.35
0.07
0.18
0.05
0.08
0.02
2.39
N/A
0.09
0.07
N/A
0.12
N/A
0.12
1.11
1.18
0.97
0.06
0.07
0.09
0.16
N/A
0.34
0.26
0.02
0.38
0.04
0.012
0.10
0.04
131
0.07
0.005
0.41
0.06
0.07
0.04
0.06
N/A
N/A
0.02
0.02
0.03
0.47
0.03
N/A
0.34
0.05
0.17
0.08
0.09
0.02
2.24
N/A
0.09
0.05
N/A
0.13
N/A
0.14
1.31
1.32
1.13
0.07
0.05
0.08
0.14
N/A
0.30
0.23
0.01
0.44
0.05
0.009
0.09
0.04
0.08
0.005
0.44
0.06
0.07
0.04
0.07
N/A
N/A
0.02
0.02
0.03
0.53
0.03
N/A
0.35
0.05
0.17
0.10
0.09
0.02
2.24
N/A
0.09
0.05
N/A
0.13
N/A
0.14
1.36
1.38
1.13
0.07
0.05
0.09
0.14
N/A
0.30
0.24
0.01
0.48
0.06
0.009
0.09
0.04
Outside
Air
(m3/s)
0.01
0.001
0.07
0.01
0.01
0.01
0.01
0
0
0.003
0.003
0.01
0.09
0.005
0
0.06
0.01
0.03
0.01
0.01
0.003
0.38
0
0.01
0.01
0
0.02
0
0.02
0.21
0.22
0.18
0.01
0.01
0.01
0.03
0
0.05
0.04
0.002
0.07
0.01
0.002
0.02
0.01
Exhaust
air
(m3/s)
0.07
0
0
0
0
0
0
0
0
0
0
0
0
0
0.04
0
0
0
0
0.08
0
0.21
0.04
0
0
0
0
0.04
0
0
0
0
0
0
0
0
0.04
0
0
0
0
0
0
0.10
0.04
Zone
Soil Work
Step Down
Sterile Hall
Sterile Storage
Storage
Sub-Sterile
Utility Hall
Utility Janitor
Utility Room
Vestibule
AHU 1 Total
Conference
Conference Toilet
Dictation
Exam 1
Exam 2
Exam 3
Exam 4
Exam 5
Exam 6
Exam 7
Exam 8
Exam 9
Exam Hall 1
Exam Hall 2
Exam Hall 3
Exam Hall 4
Exam Hall 5
Exam Hall 6
Janitor
Lounge
Nurse Station 1
Nurse Station 2
Office
Office Hall
Reception
Reception Hall
Reception Toilet
Scheduling 1
Scheduling 2
Storage 1
Storage 2
Storage 3
Utility
Work
Work Hall
Work Toilet
X-Ray
Floor
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
2
New
0.14
0.27
0.10
0.03
N/A
0.09
0.14
N/A
N/A
0.07
10.55
0.36
N/A
0.029
0.44
0.33
0.44
0.07
0.33
0.16
0.45
0.18
0.23
0.047
0.047
0.047
0.051
0.051
0.051
N/A
0.06
0.09
0.11
0.42
0.12
0.87
0.24
N/A
0.12
0.13
N/A
N/A
N/A
N/A
0.67
0.21
N/A
0.43
0.13
0.24
0.09
0.03
N/A
0.08
0.13
N/A
N/A
0.06
9.52
0.33
N/A
0.026
0.40
0.30
0.40
0.06
0.30
0.14
0.41
0.16
0.21
0.043
0.043
0.043
0.046
0.046
0.046
N/A
0.05
0.08
0.10
0.38
0.11
0.78
0.22
N/A
0.11
0.12
N/A
N/A
N/A
N/A
0.60
0.19
N/A
0.38
Post-1980
0.14
0.13
0.33
0.30
0.09
0.08
0.04
0.03
N/A
N/A
0.12
0.10
0.19
0.17
N/A
N/A
N/A
N/A
0.07
0.07
11.97
10.81
0.42
0.38
N/A
N/A
0.034
0.031
0.48
0.44
0.35
0.32
0.48
0.43
0.08
0.07
0.34
0.31
0.18
0.16
0.49
0.44
0.20
0.18
0.25
0.22
0.042
0.038
0.042
0.038
0.042
0.038
0.045
0.040
0.045
0.040
0.044
0.040
N/A
N/A
0.06
0.05
0.11
0.10
0.13
0.12
0.47
0.43
0.11
0.10
0.88
0.79
0.22
0.20
N/A
N/A
0.15
0.13
0.15
0.14
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
0.81
0.73
0.18
0.17
N/A
N/A
0.54
0.48
132
Pre-1980
0.14
0.13
0.37
0.34
0.10
0.09
0.04
0.03
N/A
N/A
0.13
0.12
0.20
0.18
N/A
N/A
N/A
N/A
0.08
0.07
12.39
11.18
0.47
0.42
N/A
N/A
0.034
0.031
0.56
0.50
0.38
0.34
0.51
0.46
0.09
0.08
0.39
0.35
0.19
0.17
0.50
0.45
0.21
0.19
0.25
0.23
0.047
0.042
0.047
0.042
0.047
0.042
0.044
0.040
0.044
0.040
0.044
0.040
N/A
N/A
0.06
0.05
0.11
0.10
0.13
0.12
0.55
0.49
0.11
0.10
0.95
0.86
0.35
0.31
N/A
N/A
0.15
0.13
0.15
0.14
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
0.85
0.77
0.19
0.17
N/A
N/A
0.54
0.48
Outside
Air
0.02
(m3/s)
0.05
0.01
0.01
0
0.02
0.03
0
0
0.01
1.82
0.06
0
0.005
0.07
0.05
0.07
0.01
0.05
0.03
0.07
0.03
0.04
0.01
0.01
0.01
0.01
0.01
0.01
0
0.01
0.02
0.02
0.07
0.02
0.13
0.04
0
0.02
0.02
0
0
0
0
0.11
0.03
0
0.07
Exhaust
air
0.14
(m3/s)
0
0
0
0
0
0
0
0
0
0
0.05
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0.10
0
0
0
0
0
0
0
0
0.04
0
Zone
Dressing Room
Elevator Hall
Humid
Janitor
Locker
Lounge
Lounge Toilet
Mechanical
Mechanical Hall
Office
Office Hall
Office Toilet
Physical Therapy 1
Physical Therapy 2
Physical Therapy
Toilet
Storage 1
Storage 2
Treatment
Undeveloped 1
Undeveloped 2
Utility
Work
AHU 2 Total
Floor
3
3
3
3
3
3
3
3
3
3
3
3
3
3
New
0.022
0.15
0.050
N/A
0.09
0.62
N/A
N/A
0.11
1.52
0.30
N/A
1.09
0.36
0.020
0.14
0.045
N/A
0.08
0.56
N/A
N/A
0.10
1.37
0.27
N/A
0.98
0.33
Post-1980
0.025
0.022
0.16
0.14
0.057
0.051
N/A
N/A
0.09
0.08
0.62
0.56
N/A
N/A
N/A
N/A
0.11
0.10
1.72
1.55
0.29
0.27
N/A
N/A
1.22
1.10
0.39
0.35
Pre-1980
0.024
0.022
0.18
0.17
0.062
0.056
N/A
N/A
0.10
0.09
0.68
0.62
N/A
N/A
N/A
N/A
0.11
0.10
1.94
1.75
0.30
0.27
N/A
N/A
1.40
1.26
0.42
0.38
Outside
Air
0.003
(m3/s)
0.02
0.01
0
0.01
0.09
0
0
0.02
0.25
0.04
0
0.18
0.06
Exhaust
air
0
(m3/s)
0
0
0
0
0
0.15
0
0
0
0
0.04
0
0
3
3
3
3
3
3
3
3
N/A
N/A
N/A
0.30
N/A
N/A
N/A
0.44
11.86
N/A
N/A
N/A
0.27
N/A
N/A
N/A
0.39
10.67
N/A
N/A
N/A
0.29
N/A
N/A
N/A
0.49
12.84
N/A
N/A
N/A
0.32
N/A
N/A
N/A
0.58
14.08
0
0
0
0.04
0
0
0
0.07
1.90
0.07
0
0
0
0
0
0
0
133
N/A
N/A
N/A
0.26
N/A
N/A
N/A
0.44
11.56
N/A
N/A
N/A
0.28
N/A
N/A
N/A
0.52
12.67
Occupancy Schedules
1
Weekdays
Saturday
Sunday, Holiday
0.9
0.8
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A39 Occupancy schedule for Outpatient Health Care
A2.15. Warehouse
Table A33 summarizes the zones modeled in CONTAM for the Warehouse, their respective
sizes, and maximum occupancy.
Table A33 Summary of zones in Warehouse
Zone
Office
Fine Storage
Bulk Storage
Restroom
Area
(m2)
233
1393
3205
4
Height
(m)
4.27
8.53
8.53
4.27
Maximum
occupancy
5
0
0
0
Geometry:
4598 m2 footprint, one-story building with flat roof. The EnergyPlus model has three zones.
Only the Office zone is 4.267 m high. The area above the Office is open to the Fine Storage,
adding to the volume of that zone. The remaining zones are all 8.534 m high. In the CONTAM
model, a Restroom (shaded in Figure A40) with a footprint of 2 m 2 m was carved out of the
Office.
134
Large interior leakage paths were defined as follows:
Between Bulk and Fine Storage zones, a single large leakage path of 32 m2 is modeled;
Between Restroom and Office zones, a 0.025 m2 door undercut is modeled.
Bulk storage
70.09 m
100.58 m
Fine storage
Office (fine
storage above)
RR
25.91 m
30.48 m
9.14 m
19.81 m
45.72 m
Figure A40 Floor plan of Warehouse (height 8.534 m, except for
Office which is 4.267 m high)
HVAC systems:
For all building vintages, the EnergyPlus model has two CAV systems. One serves the Office
and the other serves the Fine Storage zone. The supply air, return air, outside air, and exhaust
flow rates modeled in CONTAM are listed in Table A34. The exhaust flow rate for the Restroom
is modeled only in CONTAM, not in EnergyPlus.
The EnergyPlus model specifies a constant rate of air exchange in the Bulk Storage zone
(0.00025 m3/s/m2 or 0.80 m3/s). This zone also has no mechanical supply air. Thus, this is a
method to drive air movement in the building. In CONTAM, a dedicated ventilation fan supplies
0.80 m3/s of outdoor air. The Bulk Storage also has a unit heater in EnergyPlus that recirculates
air locally within the zone and does not impact whole-building airflow or introduce outside air.
Therefore, the unit heater is not modeled in CONTAM.
In EnergyPlus, neutral building pressurization is modeled in all zones. To pressurize the building
in CONTAM, less air is returned than is supplied to each zone. For all building vintages, the
return airflow rate is equal to the supply airflow rate minus the outside air requirement.
135
Table A34 Summary of CAV system flow rates (m3/s) in Warehouse
Zone
New
Post-1980
Supply Return Supply Return
Pre-1980
Supply Return
Office
Fine Storage
Bulk Storage
Restroom
1.27
5.03
N/A
N/A
2.10
9.29
N/A
N/A
1.22
4.68
N/A
N/A
1.87
8.68
N/A
N/A
1.82
8.33
N/A
N/A
2.05
8.94
N/A
N/A
Outside
Air
(m3/s)
0.05
0.35
0.80
0
Exhaust
air
(m3/s)
0
0
0
0.03
Schedules:
The HVAC and exhaust fans operate on the following schedule:
Weekdays: 6:00 a.m. to 5:00 p.m., off otherwise
Saturdays: 7:00 a.m. to 4:00 p.m., off otherwise
Sundays and holidays: off all day
Outside air for AHU 1 is supplied according to this schedule as well.
Occupants:
The peak number of people for each zone is listed in Table A33. Occupants in all building zones
are scheduled according to Figure A41. There is a different occupancy schedule for weekdays,
and Saturdays. Sundays and holidays are unoccupied.
Occupancy Schedules
1
Weekday
0.9
Saturday
0.8
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A41 Occupancy schedule for Warehouse
136
A2.16. Midrise Apartment
Table A35 summarizes the zones modeled in CONTAM for the Warehouse, their respective
sizes, maximum occupancy, and outside air rates.
Geometry:
784 m2 footprint, four-story building with flat roof. The EnergyPlus model has 9 zones per floor.
All floors have identical floor plans. In the CONTAM model, a Stairwell and Elevator Shaft
(shaded in Figure A42) with footprints of 1.68 m 4.0 m each were carved out of the Corridors.
Large interior leakage paths were defined as follows:
A stairwell is defined using CONTAM’s stair shaft model for closed treads and zero
people;
An elevator shaft is defined using CONTAM’s elevator shaft model.
Table A35 Summary of zones and outside air rates in Midrise Apartment
Zone
Floor
G SW APT
G NW APT
OFFICE
G NE APT
G N1 APT
G N2 APT
G S1 APT
G S2 APT
M SW APT
M NW APT
M SE APT
M NE APT
M N1 APT
M N2 APT
M S1 APT
M S2 APT
T SW APT
T NW APT
T SE APT
T NE APT
T N1 APT
T N2 APT
T S1 APT
T S2 APT
T CORRIDOR
G CORRIDOR
M CORRIDOR
1
1
1
1
1
1
1
1
2,3
2,3
2,3
2,3
2,3
2,3
2,3
2,3
4
4
4
4
4
4
4
4
4
1
2,3
Area
(m2)
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
88
78
78
78
Height
(m)
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
3.05
Occupants
2.50
2.50
2.00
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
2.50
0
0
0
Outside Air
(m3/s)
0.042
0.042
0.020
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0.042
0
0
0
Note: The “G” means ground, “M” means middle, and “T” means top. “APT” is apartment.
HVAC systems:
137
For all building vintages, the EnergyPlus model has 24 packaged single-zone constant-volume
systems, each serving a zone. In EnergyPlus, the systems do not supply outdoor air to the spaces,
and there is no mixing of air between the zones. Thus, they are modeled as individual supply air
fans in CONTAM for each zone. The rates are equal to the outside air flow rate listed in
Table A35. There are no exhaust fans modeled in this building.
In EnergyPlus, the Corridors have a unit heater that recirculates air locally within the zone and
does not impact whole-building airflow or introduce outside air. Therefore, they are not modeled
in CONTAM.
Schedules:
All the HVAC system fans operate 24 hours per day every day of the year. Outside air is also
supplied all of the time for the apartments. Outside air is supplied from 8:00 a.m. to 5:00 p.m. on
weekdays for the Office. No outside air is supplied to the Office on weekends or holidays.
Occupants:
The peak number of people for each zone is listed in Table A35. Occupants in all building zones
are scheduled according to Figure A43. There are two different occupancy schedules. One
schedule for the apartments, and one for the Office. The Office is unoccupied on weekends and
holidays.
NW
4m
16.92 m
N1
N2
4m
Corridor
stair
SW
11.58 m
NE
elev
S1
S2
11.58 m
11.58 m
SE or Office
11.58 m
46.33 m
Figure A42 Floor plan of Midrise Apartment (height 3.05 m)
138
7.62 m
1.68 m
7.62 m
Apartment
- Every day
Office - Weekday
Occupancy
Schedules
1
0.9
0.8
0.7
Fraction
0.6
0.5
0.4
0.3
0.2
0.1
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Figure A43 Occupancy schedules for Midrise Apartment
139
Appendix B Detailed calculated contaminant concentration predictions
B1. Full Service Restaurant
Dining
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Kitchen
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Daily average contaminant
concentrations
Mean Min.
Max.
StdDev
1474
1235
1579
73
23
3
53
10
10
1
32
5
47
34
62
5
Daily peak contaminant
concentrations
Mean
Min.
Max.
StdDev
2210
1830
2433
114
37
5
75
13
15
2
44
7
158
41
343
56
Daily average contaminant
concentrations
Mean Min.
Max.
1167
1020
1255
28
4
62
13
1
42
38
27
53
Daily peak contaminant
concentrations
Mean
Min.
Max.
1606
1352
1762
45
7
86
21
2
61
130
31
341
StdDev
49
12
7
5
141
StdDev
82
16
10
64
B2. Hospital
1F ER Exam 3
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
1F ER Nurse’s
Station
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
1F Lobby
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
2F ICU
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
2F ICU Patient
Room 3
3
CO2, mg/m
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
2F Operating
Room 2
3
CO2, mg/m
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Daily average contaminant
concentrations
Mean Min.
Max.
975
919
991
17
2
37
7
1
24
65
51
69
Daily average contaminant
concentrations
Mean Min.
Max.
862
764
908
6
1
14
5
0
18
198
123
224
Daily average contaminant
concentrations
Mean Min.
Max.
860
751
914
6
1
12
5
0
20
206
108
242
Daily average contaminant
concentrations
Mean Min.
Max.
865
795
897
10
1
23
6
0
20
119
84
132
Daily average contaminant
concentrations
Mean Min.
Max.
877
780
922
10
1
21
6
0
21
175
88
202
Daily average contaminant
concentrations
Mean Min.
Max.
824
808
832
18
2
40
7
1
21
47
38
55
StdDev
13
7
4
3
Daily peak contaminant
concentrations
Mean
Min.
Max.
1052
982
1070
28
4
54
12
1
33
68
58
75
StdDev
16
10
6
3
StdDev
52
3
3
24
Daily peak contaminant
concentrations
Mean
Min.
Max.
946
781
1026
10
1
19
8
1
23
214
169
226
StdDev
89
3
4
11
StdDev
55
2
3
30
Daily peak contaminant
concentrations
Mean
Min.
Max.
947
765
1037
10
1
21
8
1
28
225
148
243
StdDev
95
3
4
19
StdDev
37
5
3
11
Daily peak contaminant
concentrations
Mean
Min.
Max.
938
820
990
18
3
39
10
1
26
127
106
134
StdDev
64
6
4
5
StdDev
46
4
3
24
Daily peak contaminant
concentrations
Mean
Min.
Max.
960
805
1034
17
2
38
9
1
30
190
118
203
StdDev
79
6
5
14
StdDev
3
8
4
3
Daily peak contaminant
concentrations
Mean
Min.
Max.
855
836
869
30
5
58
11
1
31
49
42
60
StdDev
5
11
5
4
142
3F Lab
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
3F Nurse’s
Station Lobby
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
3F Patient Room
3
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
3F Patient Room
4
3
CO2, mg/m
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
5F Dining
3
CO2, mg/m
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
5F Office 2
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
(Hospital continued)
Daily average contaminant
concentrations
Mean Min.
Max.
StdDev
870
762
920
58
8
1
19
4
6
0
19
3
178
105
205
23
Daily peak contaminant
concentrations
Mean
Min.
Max.
962
778
1046
14
2
28
9
1
24
192
141
206
StdDev
101
5
4
14
Daily average contaminant
concentrations
Mean Min.
Max.
842
749
881
6
1
14
5
0
17
154
110
171
StdDev
48
3
3
17
Daily peak contaminant
concentrations
Mean
Min.
Max.
918
759
982
10
2
20
8
1
22
166
146
173
StdDev
82
4
4
5
StdDev
42
4
3
22
Daily peak contaminant
concentrations
Mean
Min.
Max.
966
827
1036
15
2
36
9
1
26
182
132
197
StdDev
73
6
4
15
StdDev
33
5
3
11
Daily peak contaminant
concentrations
Mean
Min.
Max.
930
823
984
19
3
40
10
1
27
116
96
120
StdDev
57
7
5
4
StdDev
77
4
3
14
Daily peak contaminant
concentrations
Mean
Min.
Max.
1016
768
1145
14
2
33
9
1
24
137
119
142
StdDev
133
5
4
4
StdDev
54
4
3
13
Daily peak contaminant
concentrations
Mean
Min.
Max.
948
763
1026
18
3
37
10
1
28
126
101
130
StdDev
94
7
4
4
Daily average contaminant
concentrations
Mean Min.
Max.
884
799
926
9
1
24
6
0
19
168
101
195
Daily average contaminant
concentrations
Mean Min.
Max.
861
796
892
11
1
26
6
0
20
108
75
119
Daily average contaminant
concentrations
Mean Min.
Max.
897
753
967
8
1
20
6
0
18
127
88
141
Daily average contaminant
concentrations
Mean Min.
Max.
860
751
904
10
1
24
6
0
20
116
73
129
143
B3. Medium Office
1F Core Zone
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
2F Core Zone
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
3F Core Zone
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
1F South Zone
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
2F South Zone
3
CO2, mg/m
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
3F South Zone
3
CO2, mg/m
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Daily average contaminant
concentrations
Mean Min.
Max.
1111
876
1219
8
2
18
5
0
18
192
120
287
Daily average contaminant
concentrations
Mean Min.
Max.
1110
883
1207
8
1
18
5
0
16
190
124
259
Daily average contaminant
concentrations
Mean Min.
Max.
1093
882
1201
8
1
19
5
0
16
181
122
225
Daily average contaminant
concentrations
Mean Min.
Max.
1100
832
1216
8
1
28
5
0
19
190
75
291
Daily average contaminant
concentrations
Mean Min.
Max.
1081
841
1183
9
2
30
5
0
16
181
77
254
Daily average contaminant
concentrations
Mean Min.
Max.
1058
842
1172
10
2
34
5
0
16
169
77
217
StdDev
95
3
3
36
Daily peak contaminant
concentrations
Mean
Min.
Max.
1289
966
1409
12
2
26
7
1
24
331
131
812
StdDev
126
4
4
152
StdDev
92
3
3
28
Daily peak contaminant
concentrations
Mean
Min.
Max.
1285
977
1416
12
2
26
7
1
23
319
149
685
StdDev
121
4
4
117
StdDev
87
4
3
20
Daily peak contaminant
concentrations
Mean
Min.
Max.
1261
975
1414
12
2
27
7
1
22
294
149
505
StdDev
117
5
4
69
StdDev
100
4
3
41
Daily peak contaminant
concentrations
Mean
Min.
Max.
1278
896
1405
13
2
52
8
1
29
297
106
812
StdDev
132
6
5
143
StdDev
92
4
3
31
Daily peak contaminant
concentrations
Mean
Min.
Max.
1248
909
1383
14
2
54
7
1
24
291
110
659
StdDev
121
6
4
111
StdDev
86
5
3
24
Daily peak contaminant
concentrations
Mean
Min.
Max.
1215
909
1374
15
2
57
8
1
24
270
109
486
StdDev
116
7
4
68
144
1F West Zone
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
2F West Zone
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
3F West Zone
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
(Medium Office continued)
Daily average contaminant
Daily peak contaminant
concentrations
concentrations
Mean Min.
Max.
StdDev Mean
Min.
Max.
1055
826
1161
88
1209
887
1328
11
2
25
5
17
2
42
5
0
23
3
8
1
32
170
83
263
38
294
104
720
StdDev
117
6
5
143
Daily average contaminant
concentrations
Mean Min.
Max.
1049
833
1142
11
2
26
5
0
21
166
88
233
StdDev
82
5
3
29
Daily peak contaminant
concentrations
Mean
Min.
Max.
1200
898
1328
17
2
42
8
1
29
288
115
594
StdDev
110
7
4
109
StdDev
76
5
3
21
Daily peak contaminant
concentrations
Mean
Min.
Max.
1173
900
1321
18
3
42
8
1
29
263
116
472
StdDev
105
8
4
63
Daily average contaminant
concentrations
Mean Min.
Max.
1030
834
1136
12
2
28
5
0
20
156
89
195
145
B4. Primary School
Cafeteria
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Gym
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Library/Media
Classroom
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Offices
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Pod 1 Corner
Classroom 1
3
CO2, mg/m
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Pod 1 Multiple
Classroom 1
3
CO2, mg/m
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Daily average contaminant
concentrations
Mean Min.
Max.
859
801
878
34
6
74
16
1
52
30
15
83
Daily average contaminant
concentrations
Mean Min.
Max.
1072
940
1143
23
4
48
14
1
46
70
42
146
Daily average contaminant
concentrations
Mean Min.
Max.
1137
834
1279
14
3
29
8
0
30
99
60
158
Daily average contaminant
concentrations
Mean Min.
Max.
961
816
1056
12
2
31
8
0
28
105
64
172
Daily average contaminant
concentrations
Mean Min.
Max.
977
793
1068
24
4
55
10
1
36
49
29
82
Daily average contaminant
concentrations
Mean Min.
Max.
1097
821
1226
17
3
44
10
0
31
73
35
125
StdDev
24
15
9
9
Daily peak contaminant
concentrations
Mean
Min.
Max.
1429
926
1572
50
14
98
24
2
68
215
38
913
StdDev
226
19
12
112
StdDev
50
10
8
14
Daily peak contaminant
concentrations
Mean
Min.
Max.
1444
1008
1579
33
9
65
21
2
61
364
80
1186
StdDev
191
12
11
147
StdDev
131
6
5
19
Daily peak contaminant
concentrations
Mean
Min.
Max.
1440
873
1683
20
5
41
13
1
39
235
65
773
StdDev
251
7
7
117
StdDev
65
5
5
17
Daily peak contaminant
concentrations
Mean
Min.
Max.
1130
869
1284
18
5
44
12
1
35
235
76
780
StdDev
117
7
6
102
StdDev
83
10
6
10
Daily peak contaminant
concentrations
Mean
Min.
Max.
1168
820
1325
35
9
73
16
1
47
127
34
425
StdDev
159
13
8
68
StdDev
122
7
6
15
Daily peak contaminant
concentrations
Mean
Min.
Max.
1381
856
1597
25
7
63
14
1
41
208
42
715
StdDev
236
10
7
105
146
B5. Small Hotel
Front Lounge
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Meeting Room
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Guest 209-212
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Guest 309-312
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Guest 409-412
3
CO2, mg/m
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Guest 215-218
3
CO2, mg/m
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Daily average contaminant
concentrations
Mean Min.
Max.
824
759
870
20
3
43
11
1
36
40
28
60
Daily average contaminant
concentrations
Mean Min.
Max.
839
819
847
27
3
61
13
1
41
19
16
22
Daily average contaminant
concentrations
Mean Min.
Max.
941
819
1044
8
1
25
9
1
32
181
79
278
Daily average contaminant
concentrations
Mean Min.
Max.
966
824
1054
7
1
25
9
1
29
206
86
282
Daily average contaminant
concentrations
Mean Min.
Max.
973
821
1049
7
1
26
9
1
27
212
85
281
Daily average contaminant
concentrations
Mean Min.
Max.
895
822
947
8
1
20
8
1
27
155
89
209
StdDev
35
8
6
6
Daily peak contaminant
concentrations
Mean
Min.
Max.
1156
847
1363
33
5
70
18
2
47
53
35
77
StdDev
185
11
8
9
StdDev
6
12
7
1
Daily peak contaminant
concentrations
Mean
Min.
Max.
1151
1072
1169
45
7
89
21
2
60
26
22
32
StdDev
17
16
9
1
StdDev
45
3
5
43
Daily peak contaminant
concentrations
Mean
Min.
Max.
1050
900
1242
14
2
47
15
1
40
207
103
297
StdDev
73
6
7
50
StdDev
43
3
5
39
Daily peak contaminant
concentrations
Mean
Min.
Max.
1110
920
1257
13
1
48
14
1
39
232
115
300
StdDev
68
6
7
39
StdDev
40
4
5
35
Daily peak contaminant
concentrations
Mean
Min.
Max.
1134
918
1261
14
2
51
14
1
39
242
115
297
StdDev
61
7
7
32
StdDev
29
3
4
28
Daily peak contaminant
concentrations
Mean
Min.
Max.
965
864
1043
14
2
34
12
1
38
179
104
238
StdDev
41
5
6
30
147
Guest 315-318
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Guest 415-418
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
(Small Hotel continued)
Daily average contaminant
Daily peak contaminant
concentrations
concentrations
Mean Min.
Max.
StdDev Mean
Min.
Max.
955
840
1041
42
1085
917
1239
7
1
19
3
13
2
33
8
1
28
5
13
1
41
204
106
279
38
233
123
297
StdDev
64
6
6
39
Daily average contaminant
concentrations
Mean Min.
Max.
975
842
1048
7
1
20
9
1
28
217
109
280
StdDev
61
7
7
32
StdDev
40
4
5
35
148
Daily peak contaminant
concentrations
Mean
Min.
Max.
1134
933
1268
14
2
35
13
1
42
249
130
306
B6. Stand-Alone Retail
Back Space
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Core Retail
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Front Retail
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Point of Sale
CO2, mg/m3
Ozone, μg/m3
PM 2.5, μg/m3
VOC, μg/m3
Daily average contaminant
concentrations
Mean
Min.
Max.
StdDev
846
741
1029
70
10
1
29
5
7
0
32
5
96
30
180
34
Daily peak contaminant
concentrations
Mean
Min.
Max.
StdDev
949
757
1217
121
15
2
43
7
11
1
45
7
135
38
436
73
Daily average contaminant
concentrations
Mean
Min.
Max.
StdDev
1052
865
1173
76
10
2
22
4
8
0
28
5
92
59
144
16
Daily peak contaminant
concentrations
Mean
Min.
Max.
StdDev
1283
975
1476
123
15
2
31
5
11
1
36
6
197
69
427
79
Daily average contaminant
concentrations
Mean
Min.
Max.
StdDev
988
794
1158
88
13
2
43
6
9
0
31
5
64
20
128
21
Daily peak contaminant
concentrations
Mean
Min.
Max.
StdDev
1195
845
1467
152
20
2
67
9
13
1
45
7
97
25
421
63
Daily average contaminant
concentrations
Mean
Min.
Max.
StdDev
984
794
1163
92
13
2
43
6
8
0
29
5
62
20
126
22
Daily peak contaminant
concentrations
Mean
Min.
Max.
StdDev
1190
843
1486
159
20
2
68
9
13
1
44
7
93
24
358
59
149
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