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ENERGY CENTER OF WISCONSIN Report Summary report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report report energy center Field Study of Ventilation in New Wisconsin Homes January 2003 216-1

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ENERGY CENTEROF WISCONSIN

Report Summary210-1

Life-Cycle Energy Costs andGreenhouse Gas Emissions forGas Turbine Power

April, 2002

report report report report report

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report report report report reportenergy center

Field Study of Ventilation in New Wisconsin Homes

January 2003

216-1

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Report 216-1

Field Study of Ventilation in New Wisconsin Homes

January 2003

Prepared by

Scott Pigg Senior Project Manager

595 Science Drive Madison, WI 53711-1076

Phone: 608.238.4601 Fax: 608.238.8733

Email: [email protected] www.ecw.org

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Copyright © 2003 Energy Center of Wisconsin All rights reserved

This report was prepared as an account of work sponsored by the Energy Center of Wisconsin (ECW). Neither ECW, participants in ECW, the organization(s) listed herein, nor any person on behalf of any of the organizations mentioned herein:

(a) makes any warranty, expressed or implied, with respect to the use of any information, apparatus, method, or process disclosed in this report or that such use may not infringe privately owned rights; or

(b) assumes any liability with respect to the use of, or damages resulting from the use of, any information, apparatus, method, or process disclosed in this report.

Project Manager Scott Pigg Energy Center of Wisconsin

Acknowledgements This report is funded in part by the Wisconsin Department of Administration, Division of Energy, through the Wisconsin Focus on Energy Pilot Program. Additional funding was provided by the Wisconsin Energy Star Homes Program and by We Energies.

Field work for this study was conducted by Richard Hasselman and Scott Pigg of the Energy Center of Wisconsin and Greg Dalhoff of Dalhoff and Associates. Brett Bergee of the Energy Center of Wisconsin provided administrative support.

The Harvard School of Public Health provided supplies and test analysis services for the passive tracer gas tests in the study. We gratefully acknowledge the assistance of Bob Wecker in this regard.

Finally, we acknowledge the following people who provided advice and guidance throughout the study:

Norman Bair, Wisconsin Department of Administration Ed Carroll, Wisconsin Energy Conservation Corporation Jim Mapp, Wisconsin Department of Administration Mary Meunier, Wisconsin Department of Administration Pat Mundstock, We Energies Joe Nagan, Home Building Technology Services and Wisconsin ENERGY STAR homes Program Technical Director Greg Nahn, Wisconsin Energy Conservation Corporation

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Contents Report Summary............................................................................................................................................................1

Introduction ...................................................................................................................................................................3 Background and Objective.........................................................................................................................................3 Approach....................................................................................................................................................................6

Recruitment of Study Participants ........................................................................................................................6 Testing and Monitoring.........................................................................................................................................7

Results .........................................................................................................................................................................11 Measured Air Leakage .............................................................................................................................................11 Mechanical Ventilation ............................................................................................................................................12

Mechanical Ventilation Rates and ASHRAE 62.2p............................................................................................15 Incidental Mechanical Ventilation ......................................................................................................................17

Carbon Dioxide Concentration ................................................................................................................................20 Passive Tracer Gas Tests..........................................................................................................................................22 Humidity ..................................................................................................................................................................26

Conclusions .................................................................................................................................................................29

References .................................................................................................................................................................435

Appendix A: Additional Details ................................................................................................................................A-1 Appendix B: CO2, Temperature and Humidity Plots…………………………………………………………….…B-1

Andrea
Appendix C: Occupancy Log (sample).......................................................................................................................C-1
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Tables and Figures Table 1, Sample disposition for homes recruited randomly by telephone. ....................................................................6

Table 2, Study participants by group and type of ventilation. .......................................................................................7

Table 3, Study participant characteristics ......................................................................................................................9

Table 4. Mechanical Ventilation Use by Site, by type of ventilation in ascending order of ventilation rate..............13

Table A1, Measured air leakage by site.......................................................................................................................36

Program .......................................................................................................................................................................36

Non-Program ...............................................................................................................................................................36

Table A2, Measured Flow rates for ventilation devices, clothes dryers and water heaters (cfm)................................37

Table A3, Central ventilation system descriptions. .....................................................................................................38

Table A4, Occupancy, by site (based on occupancy log data).....................................................................................39

Table A5, Furnace details. ...........................................................................................................................................40

Table A5, Furnace details. ...........................................................................................................................................41

Table A6, Passive tracer gas test results ......................................................................................................................42 Figure 1, Ventilation system types in the Wisconsin ENERGY STAR Homes program……………………………..4

Figure 2, typical HRV control………………………………………………………………………………………….4

Figure 3, Bath fan monitoring………………………………………………………………………………………...10

Figure 4, Measured air leakage for study homes……………………………………………………………………..11

Figure 5, Average mechanical ventilation over monitoring period, by home within ventilation system type……….12

Figure 6, Living room CO2 concentration and relative humidity for Site G13, showing periods of HRV operation..14

Figure 7, Average time-of-day profile for water heater and clothes dryer operation, normalized for number of occupants in the home………………………………………………………………………………………………...17

Figure 8, Living room and master bedroom CO2 concentration for Site D22 (10-minute intervals)………………...20

Figure 9, Average daily occupancy profile for study homes…………………………………………………………21

Figure 10, Peak CO2 concentration by site…………………………………………………………………………..21

Figure 11, Tracer gas test results……………………………………………………………………………………..24

Figure 12, peak CO2 concentration versus tracer-gas based air exchange rate………………………………………24

Figure 13, Average indoor relative humidity versus outdoor temperature, by site…………………………………..27

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Report Summary

This report summarizes the results of a field study of winter ventilation in 24 new Wisconsin homes. Eighteen of the homes were certified under the Wisconsin ENERGY STAR Homes program; the remaining six homes were randomly sampled from construction permit records. The homes in the study had several types of mechanical ventilation equipment: Fourteeen of the homes had spot exhaust fans in bathrooms and kitchens, but no central ventilation system; 8 homes had heat recovery ventilators (HRVs); and, two homes had central exhaust-only systems. The homes ranged in size from 1,800 to 5,300 square feet, and had from two to six occupants.

Each home in the study was monitored for a two-week period late in the 2000/2001 heating season (four homes ended up being monitored in early April under more spring-like conditions). The operation of exhaust fans, HRVs, furnaces, water heaters and clothes dryers were tracked, and indoor temperature, relative humidity and carbon dioxide levels were monitored. Passive tracer gas tests were conducted on most (but not all) of the homes in the study. Measurements of exhaust device flow rates were also recorded, and a blower door test for envelope leakage was conducted. Finally, occupants maintained an hourly log of occupancy over the duration of the monitoring.

Significant findings from the study are as follows:

1. Spot exhaust fans provided very little overall mechanical ventilation. Homes without a central ventilation system generally averaged less than one cfm per occupant of mechanical ventilation. The median home had about 36 total minutes of exhaust fan run time per day, or about 12 minutes per occupant.

2. Central ventilation systems provided considerably more mechanical ventilation on average, but this ventilation was not always provided uniformly over time. All but one of the 10 central systems in the study provided an average of at least five cfm per occupant of fresh air over the two-week monitoring period. Four of the systems either ran continuously or on a regular cycling schedule throughout the period, and one ran continuously for one of the two weeks. Four systems, however, could be characterized as having had many short runs that most likely originated from bathroom calls for spot exhaust and a few very long runs under dehumidistat control. These homes had little mechanical ventilation over a significant portion of the monitoring period, though they provided more than five cfm per occupant on average.

3. Incidental ventilation from clothes dryers, power-vented water heaters, and furnace make-up air pathways provide some ventilation, but the effectiveness of this ventilation is unknown. Clothes dryers in the study ran about 90 minutes per day on average, providing about 0.5 cfm per occupant, while power vented water heaters exhausted an average of 1.1 cfm per occupant worth of stale house air over a typical daily run time of about 80 minutes. These devices are most likely to be running in the morning and evening, and run more on weekends than weekdays. While clothes dryers were mostly located in the main living space of the study homes—and could thus be expected to have an impact on ventilation in occupied rooms—water heaters were all in unfinished basement areas. In addition, most homes in the study had ductwork connected between the outdoors and the furnace return plenum to satisfy building code requirements for make-up air. This pathway could account for one cfm per occupant of fresh air, or considerably more in homes that run their furnace blower continuously.

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4. Homes in the study without central ventilation systems mostly averaged between 0.1 and 0.2 air changes per hour of actual overall ventilation. Of the 11 spot-exhaust only homes in the study with passive tracer gas results, nine had average air exchange rates that fell within the above range. In terms of air exchange per household member, ventilation in these homes mostly fell between 10 and 30 cfm per occupant. Because the study is dominated by homes from the Wisconsin Energy Star Homes program, which are somewhat tighter than the average new home, these figures may understate air exchange rates in the general population of new homes; data from other sources suggests that the average program home is about 30 percent tighter than the typical non-program new home.

5. Overall, the study revealed no homes that appeared to receive less than about 7.5 cfm per occupant on average; almost all of the homes appear to be in the range of 10 to 30 cfm per occupant. These results are based on a combined assessment of tracer gas test results and analysis of peak carbon dioxide concentrations in the study homes. In terms of air changes per hour, the homes ranged from about 0.06 to 0.39, with three out of four falling between 0.1 and 0.2 air changes per hour.

6. Nighttime ventilation in bedrooms appears to be low in some study homes. Carbon dioxide levels in master bedrooms were routinely elevated in about a third of the homes, indicating poor ventilation of these spaces during sleeping hours. These homes generally set back the thermostat at night, with the consequence that the furnace does not operate and bedroom air tends to stagnate.

7. Indoor humidity in the study homes mostly ranged from reasonable to somewhat dry. For the most part, relative humidity in the study homes was in the range of 25 percent to 35 percent. Given the weather conditions during monitoring, only one home had indoor humidity that would be considered high. Two additional homes had bedroom humidity that averaged somewhat on the high side, and three homeowners reported that they sometimes had problems with window condensation.

8. Few study homes satisfied the requirements of the proposed ASHRAE 62.2p residential ventilation standard in practice, though almost all had sufficient mechanical ventilation capacity to do so. ASHRAE 62.2p has a mechanical ventilation requirement that is based both on the number of occupants and the size of the home. The standard also provides a “credit” for natural ventilation that implies an overall target ventilation rate. For a typical new Wisconsin home, the standard targets about 40 cfm per actual occupant of which 20 is required to be provided by mechanical means. (In air change terms, this is about 0.3 air changes per hour, of which 0.15 would be provided mechanically.) All but one home had sufficient ventilation capacity to meet the 62.2p mechanical ventilation requirement. However, only two study homes with continuously operating HRVs met the standard in actual operation during the monitoring period—and only one home clearly both met the mechanical ventilation requirement operational requirements and achieved the target overall ventilation level.

9. Program homes appear to be generally comparable to non-program homes in terms of ventilation. The study was not designed to be a statistical comparison between program and non-program homes, but no large differences between the two groups emerged in terms of overall ventilation rates. Program homes are tighter on average, but they are probably also more likely to have a central ventilation system.

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Introduction

Background and Objective

New homes are commonly considered to be much tighter than older homes in terms of air leakage, a perception that has led to concern among builders and homeowners about ventilation and indoor air quality in these homes. Indeed, field research confirms that new homes are indeed tighter on average. A 1999 field study involving blower door tests on a random sample of 299 Wisconsin single-family homes showed median air leakage of 3.9 air changes per hour (at 50 Pascals pressure difference) for the 43 new homes in the sample. This is considerably lower than the median of 6.0 ACH50 for the older homes in the study (Pigg and Nevius, 2000). More than three-quarters of the new homes in the sample were below the statewide median value for air leakage.

Homes built to the standards of the Wisconsin ENERGY STAR Homes program are tighter still. This program, which has certified more than 1,000 homes statewide, since 1999 requires that certified homes have measured air leakage (cfm at 50 Pascals pressure difference) of no more than one-fourth the total shell area of the building (Carroll et al., 2002). Blower door tests for more than 900 homes certified by the program as of March 2002 show a median air change rate of 2.4 at 50 Pascals, with more than 95 percent of program homes falling below 4.0 ACH, and about one-third below 2.0 ACH.

The tightness of new homes is a cause of concern for both homeowners and builders. A 1995 survey of Wisconsin builders and insulation contractors revealed widespread concern about whether new Wisconsin homes are too tight, and are resulting in poor indoor air quality and moisture problems (ECW, 1996). To address these concerns, the Wisconsin ENERGY STAR Homes program requires that certified homes have mechanical ventilation equipment capable of providing continuous ventilation of 20 cfm for the first bedroom, plus 10 cfm for each additional bedroom. 1

1 In addition, to address combustion safety issues associated with tight homes, unvented combustion equipment is not allowed, and heating systems and water heaters are required to be power-vented.

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Several strategies are used in these homes to meet the program ventilation requirement (Figure 1):

Spot exhaust fans — making up about half of the program population, these homes have bath and kitchen exhaust fans, but no central ventilation system.

Heat recovery ventilator (HRV) — about 40 percent of the homes in the program have an HRV, which simultaneously exhausts stale house air and introduces fresh outdoor air while recovering heat from the outgoing air. (Some systems also recover the moisture in the outgoing air, these are known as energy recovery ventilators or ERVs). Several types of HRV systems are employed. A fully ducted system has supply and return registers (and ductwork) in various locations to pick up stale air from the house and provide fresh air to the living space. A ducted exhaust system has ductwork to remove stale air from specific locations (typically bathrooms and the kitchen), but feeds the supply of fresh air into the return side of the furnace air handler. A “punch-in” system has no ductwork in the living space of the house; instead, stale air is removed from the return air handler plenum and fresh air is fed into the furnace supply plenum.

Central Exhaust-Only System — about 10 percent of the homes in the program have central ventilation system. That is similar to that of a ducted exhaust HRV, except that there is no heat recovery, and no central supply of fresh air—the system exhausts stale house air, which is then replaced by fresh air through leakage paths in the building shell.

Spot exhaust fans in these homes are overwhelmingly switch- controlled; that is, they only operate when the homeowner turns them on. Central systems on the other hand usually also have automatic controls that can operate the unit on an intermittent basis or when a threshold indoor humidity has been reached. Figure 2 shows a typical HRV control panel that allows the homeowner to choose to operate the unit continuously (in either of two speeds), on an intermittent basis (20 minutes out of every hour), or whenever a target humidity level as been exceeded. In addition, a system like this would typically have push-button controls in each bathroom that would run the system at its high speed for 20 to 30 minutes whenever activated. This allows the HRV to function like a spot exhaust fan.

Figure 2, typical HRV control.

Figure 1, Ventilation system types in the Wisconsin ENERGY STAR Homes program.

51%

10% 5%

35%

4%

19%

11%

SpotExhaust

Only

HRV/ERV

CombinationHRV/Spot Exhaust

Ducted CentralExhaust Only

HRV Types

DuctedExhaust

FullyDucted

“Punch-In”

51%

10% 5%

35%

4%

19%

11%

SpotExhaust

Only

HRV/ERV

CombinationHRV/Spot Exhaust

Ducted CentralExhaust Only

HRV Types

DuctedExhaust

FullyDucted

“Punch-In”

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I n t r o d u c t i o n

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Because little data exist to document how these ventilation systems are used in practice, and whether new Wisconsin homes—particularly Wisconsin ENERGY STAR Homes—are adequately ventilated, the study that is the subject of this report was undertaken early in 2001. By intensively monitoring 24 homes over a period of two weeks each, the study sought insight into ventilation practices and air exchange rates under actual living conditions in Wisconsin homes. The homes recruited for the study were chosen to represent a mix of ventilation system types. Moreover, a fourth of the study group (six homes) was devoted to new Wisconsin homes that did not participate in the Wisconsin ENERGY STAR Homes Program.

A brief discussion of what is meant by “adequate” ventilation is warranted. Unfortunately, there is no generally agreed-upon standard. An often-cited guideline is ASHRAE 62-1989 (ASHRAE, 1989), which calls for 0.35 air changes per hour but not less than 15 cfm per person in residences, and notes that this is typically expected to be provided by natural infiltration—an unlikely occurrence for new Wisconsin homes.

ASHRAE has been working for several years on a revised standard (62.2p) specifically for residential buildings. A recent version of this standard calls for providing mechanical ventilation capacity equivalent to 7.5 cfm per occupant plus one cfm per 100 square feet of floor space, with an assumption that an additional two cfm per 100 square feet will occur through natural ventilation (ASHRAE 2002).

Using bedrooms plus one as a proxy for occupancy, this guideline works out to a total ventilation requirement of about 33 cfm per person (or 0.28 air changes per hour) for the typical program home. Separate data on actual occupancy levels and square footage for several hundred new Wisconsin homes (Pigg, 2002) indicates that actual occupancy per unit floor area averages about 24 percent less than the bedrooms-plus-one formula would indicate. Since the proposed standard does not provide for reducing the ventilation capacity when actual occupancy is less than the bedroom proxy, it appears that the standard would require about 40 cfm per person of total ventilation for a typical home in the Wisconsin program, of which 20 cfm per person would need to be supplied by mechanical ventilation.

At the other end of the spectrum, Wisconsin commercial building code requires only 7.5 cfm/person of mechanical ventilation in office buildings. (Wisconsin has no code-mandated requirement for ventilation rates in residences, though spot exhaust ventilation is required in bathrooms and kitchens.)

The results that follow in this report attempt to put the findings in the context of some of the above benchmarks.

It is also important to recognize that air exchange in homes is a fairly complicated and variable phenomenon. Natural infiltration depends on the size and location of leaks in the building shell, as well as the highly changeable forces that drive air in and out of structures (temperature and wind). Mechanical ventilation often does not simply add to natural ventilation, and some home appliances such as clothes dryers ventilate the home even though that is not their main function.

The purpose of this study is to look at overall air exchange rates in the context of the operation of ventilation equipment and markers of poor ventilation such as elevated carbon dioxide levels and high indoor humidity. The project is focused on ventilation during typical winter conditions, which constitute the majority of the hours during which the typical Wisconsin home is “closed up.” However, by virtue of the timing of the project, several of the homes were studied under conditions that come closer to a worst-case ventilation scenario: i.e., warm days in early spring when the home is closed up, but there is little temperature difference between indoors and outdoors.

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Approach

Recruitment of Study Participants Homes for the study were recruited from several sources. Twelve of the 18 program homes were recruited randomly by telephone from a list of program participants after stratifying by ventilation system type. We were looking for a combination of homes with and without central ventilation systems, and representing a variety of central systems. Six of the 18 program participants (all in the Green Bay / Appleton area) were recruited by program staff. This was due to a combination of difficulty obtaining current telephone numbers for all program participants in this area and a desire to obtain representation of relatively rare configurations, such as central exhaust systems.

Non-program homes were recruited by telephone from a purchased random sample of construction permits issued between June 1999 and May 2000. Table 1 shows the disposition of sampled homes that were recruited by telephone. Inability to contact the homeowner was the largest source of attrition.

Table 2 shows the distribution of the study participants in terms of the type of ventilation system employed. The distribution of ventilation system types for the program participants in the study matches the program population fairly well, though the study did not include any fully ducted HRV systems. Though we expected to have only spot exhaust homes in the non-program group, in fact one home with an HRV system was recruited.

Geographically, study participants were recruited from four areas:

• Dane County (6 program homes; 2 non-program homes)

• Outagamie and Brown Counties (6 program homes; 2 non-program homes)

• Fond du Lac County (3 program homes; 1 non-program home)

• Waukesha County (3 program homes; 1 non-program)

Table 1, Sample disposition for homes recruited randomly by telephone.

Recruiting Disposition Program Homes Non-Program Homes

Participated in study 12 6

Agreed to participate, but over quota 2 6

Unable to contact 22 52

Refused participation 7 12

Not eligible 1 2

Total 44 78

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Table 2, Study participants by group and type of ventilation.

Monitoring and testing was conducted in six rounds of four homes each, beginning in early February 2001 and ending in mid-April. The first two characters of the participant ID for the homes in the study documents the round and location of the homes in the study, as follows:

The last character identifies the individual home within each round.

Table 3 shows some basic facts about each home in the study. Overall, the homes appear to be fairly typical of the program participant and non-participant populations.

Testing and Monitoring We took an approach that fell between intensive testing and monitoring of a few homes versus more cursory testing in many homes. The study protocol called for conducting testing and deploying data loggers for as many parameters as feasible by a two-person crew in a single three-hour site visit. The protocol involved:

• Measurement of interior square footages and volumes. • A blower door test of air leakage, including zone pressure diagnostic tests of air leakage between

house and garage and house and unfinished basement areas. • Measurement of exhaust device flows (using a balometer). • Deployment of source emitters and sampling tubes for passive tracer gas tests of air exchange.

Ventilation Type Program Homes Non-Program Homes

Spot exhaust only 9 5

Central exhaust only 2 0

Heat recovery ventilator (HRV) only 6 1

Combination HRV / spot exhaust 1 0

Total 18 6

D1x Dane county, first round

D2x Dane county, second round

G1x Outagamie/Brown county, first round

G2x Outagamie/Brown county, first round

F1x Fond du Lac county

W1x Waukesha county

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• Deployment of data loggers to monitor the operation of exhaust fans, central ventilation equipment, water heaters, clothes dryers, furnaces, and in some cases fuel-fired kitchen ranges and gas fireplaces.

• Deployment of sensors and data loggers to monitor indoor CO2 concentration, temperature and relative humidity in two locations: the master bedroom and a main living space such as a living room or great room.

• Measurement of outdoors CO2 levels (at the start and end of the monitoring period). • Deployment of additional data loggers to monitor temperatures at thermostats, in basements, and

outdoors. • Completion of field forms to capture details of mechanical equipment, occupant assessment of the

typical use of exhaust devices, and factors that might affect the interpretation of the CO2 data (such as presence of pets and indoor plants).

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Table 3, Study participant characteristics

a Based on interior measurements. These averaged about 85% of values from exterior measurements.

b Analysis excludes one day and night with no occupancy.

c Analysis excludes the final week of data with no occupancy.

Site ID Test Period (2001)

Stories above grade Bedrooms

Volumea

(ft3)

Floor Areaa (ft2) Occupants

Date Moved In

Program Homes

D11 02/03 - 02/17 1 3 22,700 2,720 2 08/99

D12 02/05 - 02/19 2 3 19,000 2,290 2 07/00

D14 02/06 - 02/19 2 3 35,900 3,570 4 03/00

D22 03/10 - 03/24 2 3 22,600 2,570 2 08/00

D23 03/08 - 03/22 2 3 29,900 3,410 2 11/00

D24 03/08 - 03/22 2 3 26,600 3,130 4 07/00

F11 03/20 - 04/04 1 3 22,300 2,730 5 08/00

F12 03/20 - 04/04 2 3 24,100 2,720 5 09/99

F14 03/21 - 04/04 2 3 36,800 4,890 4 11/00

G11 03/03 - 03/16 1 4 28,600 3,210 4 na

G13 03/02 - 03/16 1 3 48,200 4,910 2 na

G14 03/03 - 03/16 2 4 50,000 5,330 4 na

G22 03/29 - 04/12 1 3 27,700 3,280 4 07/00

G23 03/30 - 04/12 1 3 20,200 2,450 4 na

G24 03/30 - 04/12 1 3 20,700 2,550 4 10/00

W11 02/16 - 03/03 1 2 15,000 1,800 2 10/00

W12 02/18 - 03/04 2 4 40,800 4,750 4 04/00

W14 02/19 - 03/04 2 4 32,800 3,780 5 04/00

Non-Program Homes

D13 02/05 - 02/19b 1 3 16,700 2,000 4 07/99

D21 03/10 - 03/25c 2 4 39,900 3,590 4 12/99

F13 03/21 - 04/04 2 3 18,900 2,220 2 11/99

G12 03/02 - 03/16 2 4 34,100 4,100 4 12/99

G21 03/29 - 04/12 1 3 19,500 2,400 4 05/00

W13 02/18 - 03/04 2 4 26,500 3,340 6 10/99

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The operational status of fans, clothes dryers and mechanical equipment was recorded with state-recording data loggers that simply logged the date and time each piece of equipment was turned on and off. The status of various devices was sensed in different ways, however. Relays on gas valves or inducer fans were typically used to monitor furnaces and water heaters. Dryers were monitored with vibration-sensing data loggers. Bath fans were monitored by mounting a small magnet on the switch rocker; the magnetic field then opened or closed the contacts of a nearby miniature magnetic reed switch depending on the switch position (Figure 3). This arrangement was somewhat more obtrusive than we would have liked, but it was the only solution we found that could be implemented within the time limits of the site visit. We experienced a few sensor failures with this arrangement, and a few rarely used bathrooms went unmonitored, but overall data recovery from bath fan use was good.

Kitchen range exhaust hoods proved particularly difficult to monitor. In a few cases, we improvised sail-switch type sensors that closed a set of contacts whenever there was airflow in the exhaust duct. In other cases, we simply asked the occupants to record whenever they used the range hood. However, a number of range hoods went unmonitored; the homeowners for most of these sites told us they rarely used the range hood (Site D14 stands as one exception).

Heat recovery ventilators were typically monitored by recording temperatures (at two points in the system) and total current draw every two minutes. All other temperature, relative humidity and CO2 concentration sensors were sampled and recorded every ten minutes.

In addition to all of the above, the homeowners maintained an hourly log of occupancy by household member, with provisions for noting the presence of visitors and whether anyone was engaging in strenuous activity that might significantly affect CO2 generation. A sample page from an occupancy log is included in Appendix C.

Figure 3, Bath fan monitoring

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Results

Measured Air Leakage

Figure 4 shows the distribution of measured air leakage among the homes in the study (see also Table A4 in Appendix A). Program homes had a median estimated natural infiltration rate (which we roughly estimate here as 1/20th of the air leakage at 50 Pascals) of about 0.15 air changes per hour, compared to about 0.2 ACH for non-program homes. The study homes fall into three (somewhat arbitrarily defined) categories of air leakage; very tight (<0.1 ACH), moderately tight (0.1 to 0.25 ACH), and relatively (for new construction) loose (>0.25 ACH). Three program homes fall into the very tight category, and two each of program and non-program homes would be considered to be relatively loose.

These results are consistent with other air leakage measurements on new Wisconsin homes. For example, blower door tests conducted in 1999 on a random sample of 43 new homes in Wisconsin showed a median air leakage of 0.2 ACH—identical to the median for the six non-program homes in the study. Ninety percent of the homes in that study fell between 0.1 and 0.6 ACH. Similarly, analysis of blower door test results for 975 program homes certified between 1999 and early 2002 shows a median air leakage of 0.12 ACH with 90 percent of homes falling between 0.06 and 0.2 ACH.

0

0.05

0.1

0.15

0.2

0.25

0.3

G13

G22 F14

G24 F11

G23

W14

G14

W11 D24

G11

D14

W12 D11

D22

D12 F12

D23

G21 F13

G12

W13 D21

D13

Measured ACH @ 50 Pascals / 20

(from lowest to highest by group)

Wisconsin ENERGY STAR Non-ENERGY STAR

0

0.05

0.1

0.15

0.2

0.25

0.3

G13

G22 F14

G24 F11

G23

W14

G14

W11 D24

G11

D14

W12 D11

D22

D12 F12

D23

G21 F13

G12

W13 D21

D13

Measured ACH @ 50 Pascals / 20

(from lowest to highest by group)

Wisconsin ENERGY STAR Non-ENERGY STAR

Figure 4, Measured air leakage for study homes.

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F i e l d S t u d y o f V e n t i l a t i o n i n N e w W i s c o n s i n H o m e s

12

Mechanical Ventilation

We estimated the average amount of ventilation per person by multiplying the average run-time of each piece of ventilation equipment by the flow rate measured at the start of monitoring. The data demonstrate clearly that homes with spot exhaust fans had very little mechanical ventilation compared to homes with central systems. The highest spot-exhaust-only home (G22) had less mechanical ventilation than all but one home with a central system (Figure 5)—and this home had the unusual arrangement of having one bath fan wired to a central dehumidistat.

That homes with spot exhaust devices get little total ventilation from these devices is not surprising. Occupants use these fans in bathrooms and kitchens situationally to deal with moisture and odors. The median home with spot exhaust had about 36 total minutes of exhaust fan run time per day, or about 12 minutes per occupant (Table 4). And since bath fans typically move only about 50 cfm of air when they are running, the overall volume of air moved is small.

The central systems in the study provided considerably more ventilation on average. One home (D11) had an HRV with very little run-time, but several other systems ran nearly constantly during the period of monitoring. The site with the highest mechanical ventilation (D22) employed two HRVs with no controls at all—the units simply ran 24 hours a day, seven days a week. HRVs at two other sites (F11 and F12) also ran nearly constantly, but at a considerably lower air delivery rate.

Figure 5, Average mechanical ventilation over monitoring period, by home within ventilation system type.

Overall average cfm/occupant (over 2-week period)

0

10

20

30

40

W13 D22 D12 W12 G21 D13 F13 D23 G12 D14 W11 G11 D24 G22 D11 W14 F14 G13 G14 F12 F11 D21 G24 G23

By home, from lowest to highest mechanical ventilation within type

Spot Exhaust Homes

HRV Homes

CentralExhaust-

OnlyHomes

Overall average cfm/occupant (over 2-week period)

0

10

20

30

40

W13 D22 D12 W12 G21 D13 F13 D23 G12 D14 W11 G11 D24 G22 D11 W14 F14 G13 G14 F12 F11 D21 G24 G23

Spot Exhaust Homes

HRV Homes

CentralExhaust-

OnlyHomes

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13

Table 4. Mechanical Ventilation Use by Site, by type of ventilation in ascending order of ventilation rate.

Mean Daily Operation (minutes)

Total Exhaust Capacity (cfm)

Bath Spot (combined total)

Mean Ventilation Rate (cfm/occupant)

Site and Group

# Spot Fans Spot Central

Kitchen Spot Total

Per Occupant

CentralSystem

Kitchen Spot

Bath Spot

Central System Total

Spot Exhaust Only W13 Non 3 183 na na 6.2 1.0 na na 0.0 na 0.0 D22 Prog 3 193 na 1.8 0.2 0.1 na 0.1 0.0 na 0.1 D12 Prog 4 164 na 0.0 9.3 4.6 na 0.0 0.1 na 0.1 W12 Prog 5 371 na --- 16.0 4.0 na --- 0.2 na 0.2 G21 Non 2 67 na na 44.1 11.0 na na 0.2 na 0.2 D13 Non 2 92 na na 42.3 10.6 na na 0.3 na 0.3 F13 Non 3 152 na na 26.4 13.2 na na 0.4 na 0.4 D23 Prog 5 296 na 6.4 29.3 14.6 na 0.2 0.3 na 0.5 G12 Non 6 291 na 19.8 10.7 2.7 na 0.5 0.1 na 0.6 D14 Prog 5 320 na --- 146 36.4 na --- 1.1 na 1.1 W11a Prog 2 204 na --- 84.4 42.2 na --- 1.3 na 1.3

G11 Prog 6 436 na 12.6 82.2 20.6 na 0.2 1.1 na 1.4 D24 Prog 5 359 na 64.5 56.0 14.0 na 2.8 0.1 na 2.9 G22 b Prog 4 183 na 0.0 634 159 na 0.0 3.3 na 3.3

Group median 199 na 6.4 35.8 12.1 na 0.2 0.25 na 0.45 HRV D11 Prog 1 165 77 --- na na 20.8 --- na 0.6 0.6 W14 Prog 0 0 70 na na na 530 na na 5.2 5.2 F14 Prog 1 58 134 na 26.9 6.7 215 na 0.3 5.0 5.3 G13 Prog 1 285 158 1.7 na na 104 0.2 na 5.7 5.9 G14c Prog 4 477 163 8.7 2.6 0.6 381 0.5 0.0 6.5 7.1 F12 Prog 1 106 97 --- na na 1418 --- na 13.8 13.8 F11 Prog 1 142 70 --- na na 1408 0.1 na 19.6 19.6 D21d Non 0 0 163 na na na 1440 na na 40.8 40.8

Group median 124 146 5.2 14.8 3.6 455 0.4 0.15 6.1 6.5 Central Exhaust G24 Prog 0 0 140 na na na 385 na na 9.4 9.4 G23 Prog 0 0 165 na na na 850 na na 24.3 24.3

Group median 0 153 na na na 617 na na 16.8 16.8 na = not applicable to this site. --- = no data for this site. aSingle switch controls bathroom light and exhaust fan. bThis site has a bathroom exhaust fan that is connected to a central dehumidistat. cHRV is “punched in” to furnace supply and return; no separate ductwork to living space. dTwo HRV units run continuously at this site; there are no controls for the HRVs.

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Between these two extremes were six homes with central systems that racked up considerable run time over the course of the monitoring, though they did not run constantly. With the exception of one site, which is discussed below, the best way to characterize how these systems operated would be “many short runs due to bathroom ventilation calls and occasional long runs under dehumidistat control.” A plot of carbon dioxide concentration and relative humidity for Site G13 exemplifies this phenomenon (Figure 6). Over the two-week monitoring interval for this site there was a consistent pattern of short early morning and late evening HRV runs that would be consistent with exhaust calls from bathroom activity. There was one very long run that began at about 5 a.m. on March 5, and lasted until almost 9 pm the following day. This run had a dramatic impact on carbon dioxide concentration in the home and relative humidity. The most likely explanation for this event is a call from the dehumidistat, especially since the period roughly corresponds with a spike in relative humidity in the home to above 40 percent. This single long event accounted for nearly two-thirds of the total HRV operation time recorded at the site.

The site that does not adhere to the above pattern (G14), had an HRV that operated on a 20-minute on, 40 minute-off cycling schedule for the first 11 days of the monitoring period, and did not operate at all the remaining 3 days. In truth, the HRV for this site probably would not have been operated at all had a program staff member present at the time of the monitoring installation not explained how the system worked to the homeowner (who then decided to run the system in its intermittent mode). This home was also equipped with a full complement of spot exhaust fans. It also involved the only “punch-in” HRV system in which stale air is picked up from the furnace return trunk and fresh air is delivered to the furnace supply trunk.

We identified installation or problems with two of the sites in the study. First, the HRV for Site D11 was improperly wired. Instead of using control wiring for the HRV, the installer wired the system so that the dehumidistat and the bathroom crank timers simply cut power to the unit. This created two problems: (a) without power to the unit, the damper intended to seal off the fresh air inlet did not close when the unit was not operating, leading to unconditioned fresh air being sucked into the furnace return plenum whenever the furnace operated; and, (b) whenever power is cut to this type of unit, it reverts to the default speed level when operation resumes—thus the homeowner effectively had no speed control.

The second HRV with identified problems was Site F12. The issue at this site was very low (to non-existent) airflow through some of the stale-air pick-ups.

Figure 6, Living room CO2 concentration and relative humidity for Site G13, showing periods of HRV operation.

Relative Humidity (%)

02mar2001 06mar2001 10mar2001 14mar2001

25

30

35

40

45

CO2 Concentration (ppm)

02mar2001 06mar2001 10mar2001 14mar2001

400

600

800

1000

1200

1400

1600 Periods of HRV operation

Relative Humidity (%)

02mar2001 06mar2001 10mar2001 14mar2001

25

30

35

40

45

CO2 Concentration (ppm)

02mar2001 06mar2001 10mar2001 14mar2001

400

600

800

1000

1200

1400

1600 Periods of HRV operation

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15

Mechanical Ventilation Rates and ASHRAE 62.2p The ASHRAE 62.2p mechanical ventilation standard requires the provision and operation of mechanical ventilation equaling at least 7.5 cfm per occupant plus 1 cfm per 100 square feet of floor area. The standard states that the number of occupants is to be taken as the number of bedrooms in the home plus one, unless higher occupancy is known.

Table 5 shows the calculated 62.2p mechanical ventilation requirement for the homes in the study, along with the observed mechanical ventilation rate during monitoring. The calculated 62.2p mechanical ventilation requirement was based on the higher of actual occupants in the home or the bedrooms-plus-one proxy. As Table 5 shows, the standard calls for 40 to 90 cfm of mechanical ventilation depending on the size of the home and number of occupants in the home.

All but one home (Site W14, which fell just short of the required capacity) had sufficient total mechanical ventilation to meet the 62.2p requirement. However, in actual operation only two homes clearly met the mechanical ventilation requirements of 62.2p over the entire period of monitoring—these were both homes with HRVs that ran continuously (F11 and D21).

Two additional homes were close to meeting the 62.2p requirements. Site F12 met the requirement if the number of occupants in the home is taken to be the number of household members (five). But the homeowner for this site operates a daycare; the average number of people in the home during the day on weekdays was about 7.5 over the monitoring period. Calculated at an occupancy of seven or eight persons, the continuously operating HRV at this site does not quite meet the 62.2p requirements.

Site G23 had an average ventilation rate that exceeded the 62.2p level. The cycling of this system did not meet the 62.2p requirement of operation at least once every 12 hours over the entire monitoring period (also, the 62.2p standard would reduce the system’s “effective ventilation rate” to 1/3 of the nominal value due to the intermittent operation). This system ran infrequently during the first week of monitoring, but ran constantly for the second week.

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16

Table 5, Actual mechanical ventilation and ASHRAE 62.2p calculated requirement, expressed in terms of three measures of ventilation rate.

Total cfm Air Changes per Hour

cfm per Actual Occupant

Site Group ASHRAE

62.2p Actual avg.

ASHRAE 62.2p

Actual avg.

ASHRAE 62.2p

Actual avg.

Meets ASHRAE

62.2p

Spot Exhaust Only W13a Non 78 0 0.18 0.00 13.1 0 D22 Prog. 56 0 0.15 0.00 27.9 0.1 D12 Prog. 53 0 0.17 0.00 26.5 0.1 W12 Prog. 85 1 0.13 0.00 21.3 0.2 G21 Non 54 1 0.17 0.00 13.5 0.2 D13 Non 50 1 0.18 0.00 12.5 0.3 F13 Non 52 1 0.17 0.00 26.1 0.4 D23 Prog. 64 1 0.13 0.00 32.1 0.5 G12 Non 79 2 0.14 0.00 19.6 0.6 D14 Prog. 66 4 0.11 0.01 16.4 1.1 W11 Prog. 41 3 0.16 0.01 20.3 1.3 G11 Prog. 70 6 0.15 0.01 17.4 1.4 D24 Prog. 61 12 0.14 0.03 15.3 2.9 G22 Prog. 63 13 0.14 0.03 15.7 3.3 HRV D11 Prog. 57 1 0.15 0.00 28.6 0.6 W14 Prog. 75 26 0.14 0.05 15.1 5.2 F14 Prog. 79 21 0.13 0.03 19.7 5.3 G13 Prog. 79 12 0.10 0.01 39.6 5.9 G14 Prog. 91 28 0.11 0.03 22.7 7.1 F12 a Prog. 65 69 0.16 0.17 12.9 13.8 Maybe F11 a Prog. 65 98 0.17 0.26 13.0 19.6 Yes D21 Non 73 163 0.11 0.25 18.4 40.8 Yes Central Exhaust G24 Prog. 56 38 0.16 0.11 13.9 9.4 G23 Prog. 55 97 0.16 0.29 13.6 24.3 Maybe

Overall Median 64 5.0 0.15 0.0 17.9 1.4 Minimum 41 0.0 0.10 0.0 12.5 0.0

Maximum 91 163.2 0.18 0.3 39.6 40.8 aActual occupancy higher than bedrooms-plus-one proxy, so actual occupancy used as basis for ASHRAE 62.2p calculations.

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17

Incidental Mechanical Ventilation

Water Heaters and Clothes Dryers

All of the homes in the study had clothes dryers and all but one had power-vented water heaters. What these devices have in common is that they act as exhaust-only mechanical ventilation devices when they operate. The same might also be said of furnaces, but nearly all of the homes in the study had sealed-combustion furnaces that do not use house air for combustion.

We therefore attempted to measure the exhaust airflow from clothes dryers and water heaters, as well as log their operation during the monitoring period. Neither attempt was completely successful. There were problems with obtaining reliable measurements of exhaust airflow from water heaters in particular, and the vibration-sensing data loggers that we attempted to use to record dryer use proved problematic.

Nonetheless, we did obtain some usable data, which are summarized in Table 6. The results suggest that clothes dryers exhaust about 0.5 cfm per occupant on average, and water heaters exhaust a slightly higher 1.1 cfm per occupant. Of course, these averages are not continuous rates, but a blend of periods when the devices are not operating at all and periods when they are. For the typical home in the study, the clothes dryer run about twice as long on weekend days as it does on weekdays. Water heaters run about 20 percent more on weekend days than during the workweek. The devices have similar daily use profiles characterized by morning and evening periods when they are running most frequently, though water heaters have a greater concentration of their run time earlier in the morning (Figure 7).

The analysis presented here does not look at how clothes dryers and water heaters affect air exchange in the main living space of the home. Since the water heaters are located in unfinished basement areas, it is questionable how much they affect air exchange in living spaces. On the other hand, all but four of the clothes dryers in the study were located on the first or second floor, so these appliances probably have a more direct impact on ventilation of the living space.

Figure 7, Average time-of-day profile for water heater and clothes dryer operation, normalized for number occupants in the home.

midnight 6am noon 6pm

0

1

2

3Water heaters

Clothes dryers

Mean minutes of operation per occupant

Hour of the daymidnight 6am noon 6pm

0

1

2

3Water heaters

Clothes dryers

Mean minutes of operation per occupant

Hour of the day

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Table 6, Clothes dryer and water heater operation and incidental ventilation.

Measured Exhaust Flow

(cfm)

Mean Operation Time (minutes per day)

Mean Ventilation (cfm per occupant)

Clothes Dryer Clothes Dryer Site

Dryer Location

Clothes Dryer

Water Heater low high avg.

Water Heater low high avg.

Water Heater

D11 1st floor 60 57 D12 1st floor 40 40 38 0.5 D13 basement 30 45 113 0.9 D14 1st floor 25 83 92 87 104 0.4 0.4 0.4 D21 1st floor 50 85 110 1.6 D22 2nd floor 70 58 4 11 7 46 0.1 0.3 0.2 0.9 D23 1st floor 45 50 79 1.4 D24 1st floor 52 44 60 52 56 0.4 0.5 0.5 F11 basement 72 38 9 36 22 133 0.1 0.4 0.2 0.7 F12 1st floor 82 40 234 288 261 242 2.7 3.3 3.0 1.3 F13 1st floor 50 71 83 77 134 2.3 F14 1st floor 54 74 125 154 139 43 1.2 1.4 1.3 0.5 G11 1st floor 25 80 111 134 123 125 1.7 G12 1st floor 63 (atmos.) 107 107 107 1.2 1.2 1.2 G13 1st floor 67 31 G14 1st floor 97 45 88 111 99 141 1.1 G21 1st floor 29 150 164 157 0.8 0.8 0.8 G22 1st floor 75 75 122 1.6 G23 basement 56 48 75 92 84 64 0.7 0.9 0.8 0.5 G24 1st floor 72 77 104 90 49 0.6 W11 basement 20 45 27 64 46 71 0.2 0.4 0.3 1.1 W12 1st floor 85 W13 1st floor 21 115 80 1.1 W14 1st floor 65 92 48 63 55 55 0.4 0.6 0.5 0.7

Median 54 50 77 92 87 80 0.4 0.6 0.5 1.1 Minimum 20 38 4 11 7 31 0.1 0.3 0.2 0.5 Maximum 97 115 234 288 261 242 2.7 3.3 3.0 2.3

Notes:

Blanks indicate no data available.

Clothes dryer operation time and ventilation given as a low/high range due to uncertainty in interpretation of run-time data collected with vibration sensing data loggers. Average is the midpoint of the range.

Data are weighted to reflect correct proportional contribution of weekends and weekdays.

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Furnace Operation

Furnace operation affects ventilation in two ways. First, furnace air handler operation tends to mix the air in the home. By itself, this does not affect the amount of fresh air introduced, but it does tend to dilute and distribute pollutants and markers such as carbon dioxide. We hypothesize that it was night thermostat setbacks that contributed to the elevated bedroom CO2 levels observed in some homes; without air furnace handler operation, these bedrooms were under ventilated during sleeping hours.

Second, make-up air ductwork into furnace returns represents another potential source of fresh air supply. Wisconsin’s residential building code requires make-up air for exhaust fans and clothes dryers. Many builders provide for this make-up air by installing a six-inch diameter duct from outside to the return air plenum of the furnace. The efficacy of the arrangement in avoiding depressurization of the house from exhaust devices is debatable, but measurements made by program staff indicate that these installations can pull a non-trivial amount of fresh air into the house whenever the furnace air handler operates. Make-up air flow typically runs 25 to 30 cfm, though many homes with zero flow have also been observed due to placement of the ductwork far upstream of the furnace (Nagan, 2002).

We neglected to measure the make-up airflow during air handler operation for the study homes, but we did monitor furnace run times during the monitoring period (see Table A5, Appendix A). The median home in the study averaged about 3.2 hours of furnace operation during the monitoring period. Based on 30 cfm of fresh air supply during air handler operation, make-up air channels might be responsible for ventilation of about one cfm per occupant under the weather conditions during the study. In general, furnace operation is quite linear with outdoor temperature, so one could expect this source of fresh air to increase in colder weather and decrease in warmer weather. And, some homeowners run their furnace blowers continuously; this would significantly increase the amount of ventilation provided via the make-up air route. Sites F14, G11 and G12 reported to us that they run their furnace fan continuously at least part of the year.

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F i e l d S t u d y o f V e n t i l a t i o n i n N e w W i s c o n s i n H o m e s

20

Carbon Dioxide Concentration

Carbon dioxide is a useful—albeit imprecise—indicator of ventilation, since the occupants with every breath generate carbon dioxide. Homes that have high ventilation per occupant tend to have low carbon dioxide concentrations as carbon dioxide exhaled by occupants is flushed out of the home. Conversely, carbon dioxide builds up to higher levels in homes that get little fresh air per occupant.

In fact, if the air exchange rate and carbon dioxide generation rates are constant, the concentration of CO2 in the home will come to an equilibrium level such that each cubic foot of carbon dioxide exhaled by the occupants is balanced by a cubic foot of carbon dioxide removed from the space through air exchange. Under these equilibrium conditions, the concentration of carbon dioxide in the space (or more properly, the elevation of CO2 concentration above outdoor levels) can be used as a direct measure of ventilation rate. For the CO2 generation rate of an average adult engaged in light activity (0.011 cfm), an air exchange rate of 15 cfm/occupant would be expected to result in an equilibrium indoor CO2 concentration of 733 ppm above ambient (which we found to average about 400 ppm). Similarly, an air exchange rate of 7.5 cfm/occupant would result in an elevation of 1467 ppm above ambient.

But not all occupants are average adults (or even adults period) and activity levels can be expected to vary. Moreover, it may take 8 hours or longer for CO2 levels to reach equilibrium at air exchange rates typical of new homes. If equilibrium is not reached, then ventilation rates based on an assumption of equilibrium conditions will be overestimated.

At the same time, peak CO2 levels in a home provide an upper limit on the ventilation rate, assuming that assumptions about the average CO2 generation rate hold (Persily, 1997). In short, high CO2 levels are indicative of inadequate ventilation, but low levels do not necessarily mean adequate ventilation.

A typical CO2 time-series trace from the study is shown in Figure 8 (plots of all homes in the study are provided in Appendix B). There is a definite diurnal cycle in CO2 concentration associated with occupants coming and going. The timing of these peaks and troughs varies from site to site and between living room and bedrooms, based on the occupancy patterns of the household members.

Figure 8, Living room and master bedroom CO2 concentration for Site D22 (10-minute intervals).

CO

2 C

once

ntra

tion

(ppm

)

Mar-10 Mar-14 Mar-18 Mar-22

400

600

800

1000

1200 Living Room

Mar-10 Mar-14 Mar-18 Mar-22

400

600

800

1000

1200 Master Bedroom

CO

2 C

once

ntra

tion

(ppm

)

Mar-10 Mar-14 Mar-18 Mar-22

400

600

800

1000

1200 Living Room

Mar-10 Mar-14 Mar-18 Mar-22

400

600

800

1000

1200 Master Bedroom

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Figure 9 shows the overall median weekday and weekend occupancy pattern for homes in the study; additional information on the individual homes is provided in Appendix A. (There were only two instances where a monitored home was completely vacant for one or more nights. The household for Site D21 was on vacation for the second week of the monitoring period, and the Site D13 household was away overnight for one day during monitoring. These periods were generally excluded from the analysis that follows.)

As a measure of typical peak CO2 concentration, we first found the daily maximum CO2 concentration, then took the median of the daily maxima.2 The results are shown in Figure 10, along with lines showing the equilibrium concentration that corresponds with 7.5 and 15 cfm per occupant.

The data suggest that about half of the homes in the study had ventilation rates somewhere between 7.5 and 15 cfm per occupant, while the other half had ventilation rates above 15 cfm per occupant. As noted above, it is possible that the measured peak CO2 level was still well below the equilibrium level for some of these homes, though comparison with passive tracer gas tests (in the next section) suggests that the CO2 data provide a reasonable estimate of ventilation rates.

In general, bedroom peak CO2 levels are higher than living room levels and six to eight homes show bedroom peaks that are substantially higher. These tend to be homes with substantial night setbacks to the thermostat, which result in little nighttime furnace runtime, and thus little bedroom air circulation. Similar elevated bedroom CO2 levels have been observed elsewhere (White and Lawton, 1996).

2 For sites with gas ranges—which create a large pulse of CO2 when operated—we removed periods affected by range operation.

Figure 10, Peak CO2 concentration by site.

Figure 9, Average daily occupancy profile for study homes.

0

25

50

75

100

midnight 6am noon 6pm

Median (across homes) percent of normal full occupancy

Hour of the day

weekends

weekdays

0

25

50

75

100

midnight 6am noon 6pm

Median (across homes) percent of normal full occupancy

Hour of the day

weekends

weekdays

0

500

1000

1500

2000

Carbon Dioxide ConcentrationMedian Daily Peak (ppm)

Master bedroom

Living room

Wisconsin ENERGY STAR home

Non-ENERGY STAR home

By home, from lowest to highest living room concentration

15 cfm/person

7.5 cfm/person

Equilibrium concentrationfor given ventilation ratebased on 400ppm outdoorconcentration

D21 W12 D11 F13 G12 G11 D24 D12 D13 D22 F14 D23 W14 G24 W13 D14 F11 G23 G13 F12 G21 W11 G22G140

500

1000

1500

2000

Carbon Dioxide ConcentrationMedian Daily Peak (ppm)

Master bedroom

Living room

Wisconsin ENERGY STAR home

Non-ENERGY STAR home

By home, from lowest to highest living room concentration

15 cfm/person

7.5 cfm/person

Equilibrium concentrationfor given ventilation ratebased on 400ppm outdoorconcentration

D21 W12 D11 F13 G12F13 G12 G11 D24 D12 D13D12 D13 D22 F14 D23 W14 G24 W13 D14 F11 G23 G13 F12 G21 W11 G22G14

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Passive Tracer Gas Tests

In addition to recording CO2 concentration in the homes, we also measured air exchange rates using passive tracer gas tests following the method of Dietz et al. (1986). In these tests, a constant-injection tracer gas source is left in the home (a compound known as PMCH was used), along with one or more passive sampling tubes. Analysis of the amount of tracer gas in the sampling tubes provides a measure of the average concentration of the tracer gas in the home, the reciprocal of which is a measure of air exchange rates. Because the method relies on the reciprocal of the average concentration to approximate air exchange (which is actually related to the average reciprocal concentration) errors can result if air exchange rates vary significantly during the sampling period. These errors are typically less than 30 percent (ASHRAE, 1993).

An additional source of uncertainty for this study is the degree to which the entire house can be considered to be a single well-mixed zone. Dietz et al. provide evidence of good mixing within a floor, but not necessarily across floors. However, concerns about overloading the sampling tubes (probably misplaced, in retrospect) led us to typically leaving only a single source emitter in each home. Air exchange estimates based on sampling tubes on floors with no source emitter might therefore overestimate the actual ventilation rate. Because of this, the results that follow are denoted according to whether there was a source emitter on the same floor as the sampling tube or not.

Because the method relies on detecting minute quantities of the tracer gas, handling of the emitters and sampling tubes in the field is important. Careless handling can lead to contamination of sample tubes with the tracer gas, which would lead to false estimates of air exchange rates. For this reason, a small number of duplicate sampling tubes and field blanks (sampling tubes that are never uncapped but otherwise treated the same as other sampling tubes) were also employed to ensure that the results were repeatable and not affected by handling of the emitters and sample tubes. By all indications, the field procedures were adequate in this regard.

We did not obtain tracer gas test results for all homes in the study, however. Sample tubes were temporarily unavailable when the four Fond du Lac county homes were tested (F11, F12, F13, and F14), and for unknown reasons usable results were not obtained for three additional homes. (D12, W13 and W14)

The results for the 17 homes in the study with data indicate air exchange rates that ranged from 9 to 67 cfm per occupant, with a median of 23 cfm per occupant (Figure 11). Most homes fell between 10 and 30 cfm per occupant. Expressed as air changes per hour, the homes ranged from 0.06 to 0.39 ach, with a median of 0.16 ach, and most homes falling between 0.1 and 0.2 ach.

Two homes had very high ventilation rates as measured by the tracer gas test. As has already been noted, one of these (Site D21) has two HRVs that run continuously. These HRVs exchange about 40 cfm per occupant, or about two-thirds of the observed overall ventilation rate. Natural infiltration presumably accounts for most of the remainder.

The other (Site W12) shows little mechanical ventilation and had measured air leakage that was in the middle of the study range. However, this home is a two-story home in an exposed location on a ridge top. A calculation of the likely infiltration rate during the monitoring period using the LBL model (ASHRAE, 1993) suggests a natural

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ventilation rate of almost 50 cfm per person for this home during the monitoring period, which makes the measured values of 60-70 cfm per occupant plausible.3

Despite the potential accuracy issues with both the CO2 data and the tracer gas tests, the results for the 17 homes for which usable data were obtained for both shows a reasonable correlation with equilibrium theory (Figure 12). Four sites stand out as outliers in this regard (W11, G23, G13 and D13). Possible explanations for three of these outliers are:

• Site W11 is a small house with two large dogs in addition to the two (human) household members; it is likely that the CO2 generation rate in the home is higher than the standard assumption of 0.011 cfm per human would indicate.

• Site G13 is a very tight home with long periods when no one was home. These factors make it less likely that peak CO2 levels in the home represent equilibrium levels. In fact, a “ratchet” effect can be seen in the CO2 data over the course of a week (see Appendix A); the decay in CO2 level during day when no one was home is less than the subsequent build-up each night, leading to gradually increasing CO2 concentration in the home. Also, site G13 experienced dramatic changes in air exchange rate because of the extended HRV run under dehumidistat control noted previously. Large changes in air exchange rates adversely affect the accuracy of the passive tracer gas test.

• Site G23 had dramatic changes in air exchange; the central exhaust-only system for this home ran very little during the first week of monitoring, and then ran constantly (probably under dehumidistat control) during the second week.

Figure 11 also demonstrates how peak CO2 levels are a much more sensitive indicator of air exchange rates at low exchange rates and much less sensitive at higher exchange rates. An increase from 5 cfm per occupant to 10 cfm per occupant would be expected to reduce the equilibrium CO2 concentration by 1100 ppm, but an identical increase from 30 to 35 cfm per occupant would result in a reduction of only about 50 ppm. This reinforces the notion that consistently elevated CO2 levels can be used as an indicator of low ventilation rates, but low CO2 levels don’t provide much insight into air exchange rates.

3 These results are derived as follows: LBL Effective Leakage Area=95.2 in2 mean windspeed=12.0 mph during monitoring period (based on nearby MKE airport data) mean indoor/outdoor ∆T=48.2F calculated infiltration = 95.2*sqrt(.0313*48.2+.0157*11.97^2) = 185 cfm = 46 cfm/person

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F i e l d S t u d y o f V e n t i l a t i o n i n N e w W i s c o n s i n H o m e s

24

0

20

40

60

80

G21 D14 G22 D13 G24 W11 D24 G11 G23 D22 G13 G12 D11 G14 D23 D21 W12

Average cfm/occupant

Sampled from different floor than sourceSampled from same floor as source

7.5 cfm/occupant

15 cfm/occupant

0

20

40

60

80

G21 D14 G22 D13 G24 W11 D24 G11 G23 D22 G13 G12 D11 G14 D23 D21 W12

Average cfm/occupant

Sampled from different floor than sourceSampled from same floor as source

7.5 cfm/occupant

15 cfm/occupant

0 10 20 30 40 50 60 70

0

500

1000

1500

2000

2500

D11

D13

D14

D21

D22D23

D24G11 G12

G13G21

G22

G23

G24

W11

W12

Median daily peak living room CO2 concentration (ppm)

Mean cfm/occupant (PFT test average)

Equilibrium level (based on 0.011 cfm CO2/person and 400 ppm ambient CO2)

0 10 20 30 40 50 60 70

0

500

1000

1500

2000

2500

D11

D13

D14

D21

D22D23

D24G11 G12

G13G21

G22

G23

G24

W11

W12

Median daily peak living room CO2 concentration (ppm)

Mean cfm/occupant (PFT test average)

Equilibrium level (based on 0.011 cfm CO2/person and 400 ppm ambient CO2)

Figure 11, Tracer gas test results.

Figure 12, peak CO2 concentration versus tracer-gas based air exchange rate.

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The ASHRAE 62.2p standard provides a credit of two cfm per 100 square feet of floor area for natural ventilation. When added to the mechanical ventilation requirements this implies that the standard seeks to obtain an overall air exchange rate of 7.5 cfm per person plus 3 cfm per 100 square feet of floor space.

Table 7 shows the implied 62.2p ventilation target for the homes in the study. Among the 17 homes with tracer gas data, only two had measured air exchange rates that exceeded this implied target: Sites D21 and W12 (though Site G23 comes close). Site W12 did not meet the mechanical ventilation requirement of the standard however, so among the sites with observed air exchange data, only Site D21 clearly fully met the letter and intent of ASHRAE 62.2p.

The uncertainty inherent in the CO2 data makes it more difficult to know whether the sites that did not have tracer gas test results met the 62.2p target ventilation levels, particularly the sites that met or came close to the 62.2p mechanical ventilation requirement. Calculated air change rates based on peak living room CO2 levels suggests that these homes fell short of the 62.2p targets as well.

Table 7, Implied ASHRAE 62.2p total ventilation target, by site

ASHRAE 62.2p targeta

Site Total cfm

Cfm per actual

occupant Air changes

per hour

Actual average air

changes per hourb

D11 112 55.8 0.29 0.17 D12 99 49.4 0.31 0.13 D13 90 22.5 0.32 0.16 D14 137 34.3 0.23 0.08 D21 145 36.3 0.22 0.37 D22 107 53.6 0.28 0.13 D23 132 66.2 0.27 0.12 D24 124 31.0 0.28 0.17 F11 119 23.9 0.32 0.19 F12 119 23.8 0.30 0.15 F13 97 48.3 0.31 0.17 F14 177 44.2 0.29 0.13 G11 134 33.5 0.28 0.20 G12 161 40.1 0.28 0.18 G13 177 88.7 0.22 0.07 G14 197 49.4 0.24 0.13 G21 102 25.5 0.31 0.11 G22 128 32.1 0.28 0.11 G23 104 25.9 0.31 0.28 G24 107 26.6 0.31 0.18 W11 77 38.3 0.31 0.12 W12 180 45.0 0.26 0.39 W13 145 24.2 0.33 0.22 W14 151 30.2 0.28 0.16

median 126 35.3 0.29 0.16 max 197 88.7 0.33 0.39 min 77 22.5 0.22 0.07

aASHRAE 62.2p target based on 7.5 cfm per occupant + 3 cfm per 100 square feet of floor area.

bItalics indicate air change estimated from peak CO2 data; otherwise figures are based on passive tracer gas tests where sample tubes and emitters were on the same floor.

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26

Humidity

Controlling humidity is probably the most important homeowner concern with respect to ventilation. Low humidity can lead to skin and respiratory problems as well as static electricity problems. Conversely, high humidity can create conditions for mold, dust mites and other pathogens, and can produce condensation on windows.

Relative humidity in homes tends to vary with outdoor temperature, since cold outdoor air can hold less moisture than warmer air. This trend is generally evident in the data from the study homes, most of which fell on a trend line roughly defined as relative humidity equal to outdoor temperature (Figure 13). In particular, the last group of homes that were monitored in early April (G21-G24) shows higher relative humidity and outdoor temperature than the other homes in the study.

We consider 30 to 40 percent relative humidity to be the appropriate target zone for Wisconsin homes at outdoor temperatures between 20 and 40F. Above 40F, somewhat higher relative humidity can be tolerated without risk of window condensation. At very cold temperatures, condensation may be excessive at the upper end of the above range. By this criterion, most of the homes in the study had reasonable humidity levels. Six homes had relative humidity below this target zone; these were mostly homes that were monitored during colder weather. (Relative humidity for these homes might actually be lower than the data suggest, because the sensors used to measure relative humidity were not capable of recording relative humidity below about 25 percent.)

Three homes had relative humidity above the target zone, and two of these (W14, G11) involved high humidity in bedrooms but not the main living space. One of these homes (G11) reported having had a problem with mold growth in a bedroom closet. The one home for which relative humidity in general exceeded the 40 percent threshold was the smallest home in the study with the highest occupancy density (especially considering that this household also had two large dogs). This home also had a 15-gallon aquarium.

When asked (well after the completion of monitoring) whether they had experienced any problems with window condensation, indoor humidity or odors three study participants reported occasional condensation problems (G21, F12, and F13). In addition the homeowner for site F14 reported that their HRV reduced the indoor humidity too much; they had turned off the HRV and installed a humidifier.

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Figure 13, Average indoor relative humidity versus outdoor temperature, by site.

20 25 30 35 40 45 50

20

25

30

35

40

45

50

D11 D12 D13

D14 D21D22D23

D24

F11

F12

F13F14G11

G12

G13

G14

G21

G22

G23

G24 W11

W12

W13 W14

Mean Relative Humidity (%)

(lower limit of sensor resolution)

Living roomMaster bedroom

Mean Outdoor Temperature (F)

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Conclusions Overall, the data reveal no homes that were egregiously under-ventilated (<7.5 cfm/person) on a per person basis during monitoring. The CO2 and tracer gas data suggest that nearly all of the homes in the study fall into a category of between 10 and 30 cfm/person of overall ventilation.

At the same time, it appears that very few new homes are adequately ventilated by the standards of the proposed ASHRAE 62.2p standard, For new Wisconsin homes, the proposed standard calls for a target average of about 0.3 air changes per hour of total ventilation (mechanical plus natural), but the test results from this study suggests that the average new home gets only about half that amount. Only one home in the study clearly met the overall ventilation target implied by 62.2p.

Nonetheless, it appears (based on the observed run times of the ventilation equipment) that homeowners generally do not perceive the need for ventilation at 62.2p levels. It is important to note that all but one home in the study had sufficient total mechanical ventilation capacity to meet the 62.2p requirement (and the one remaining home fell just short of the requirement). It was not a lack of ventilation capability that led to most homes falling below the 62.2p standard, but rather insufficient operation of the existing equipment.

Indoor humidity is probably the main factor that affects how people use their ventilation systems, and there was little evidence of excessive humidity among the study homes. In fact, given that humidity ranged from reasonable to somewhat dry for most of the homes in the study, ventilating these homes to 62.2p levels might lead to excessive dryness during the winter unless enthalpy recovery or mechanical humidification was also employed.

If people respond mainly to moisture and odor generation, and these tend to be proportional to the number of people in the home, then people are probably more sensitive to the per-person ventilation rate rather than air changes per hour. Two aspects of the 62.2p calculation methods lead to relatively high per-person ventilation targets. First, part of the 62.2p ventilation calculation is based on square footage of the home. The size of new homes has increased markedly in the last decade, but the number of household members has not. Second, the default approach used by the standard to estimate occupancy levels (number of bedrooms plus one) overestimates the actual number of occupants in new homes on average.

The result is that the 62.2p target overall ventilation rate is about 40 cfm per actual occupant for a typical new Wisconsin home, of which 20 cfm would need to be supplied by mechanical ventilation. This total ventilation target is 2.6 times as much ventilation per person than the old (ASHRAE 1989) minimum of 15 cfm per person. Similarly the mechanical ventilation requirement is 2.6 times what Wisconsin commercial code currently requires in commercial office buildings. Thus, although the number of air changes per hour called for by 62.2p is comparable to the previous ASHRAE standard, the new standard considerably increases the per-person ventilation requirement relative to prior standards and codes. Based on the data from the study, meeting the 62.2p mechanical ventilation requirement in a typical new Wisconsin home would require a central ventilation system running 30 minutes out of every hour, or—in homes without a central system—two bath fans running continuously.

Of course, the ostensible purpose of having part of the 62.2p standard is related to square footage is that there are indoor pollutants that are generated in proportion to the size of the home. Off gassing of volatile organic compounds from carpeting is one example. Homeowners may not easily detect these. Whether or not the ventilation levels called for by 62.2p are indeed justified thus hinges on the extent to which such pollutants are indeed present in homes and the need to dilute them with outdoor air. Unfortunately, such research was outside the resources for this project.

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F i e l d S t u d y o f V e n t i l a t i o n i n N e w W i s c o n s i n H o m e s

Since nearly all of the homes in the study already had adequate mechanical ventilation capacity to meet ASHRAE 62.2p, it does not appear that there would be substantial incremental construction costs to make new homes compliant with the standard—though there would be some additional cost to provide controls to ensure sufficient operation of the equipment as required under the standard, and homeowners would face slightly higher utility bills from operating the equipment more frequently.

It is clear from this study that central ventilation systems provide significantly more mechanical ventilation on average than homes without such systems. All but one of the homes with a central system had at least 5 cfm/person provided by mechanical ventilation alone over the monitoring period, compared to mostly trivial overall mechanical ventilation in homes without central systems or automatic controls.

However, it is also clear from this study that the existence of a central ventilation system in a home does not guarantee that it will operate in a manner that provides systematic ventilation to the home. Indeed if the homes in this study are representative, it appears that a significant proportion of the HRVs are mainly used like spot exhaust fans, with occasional long runs for dehumidification. These systems do not provide a consistent amount of ventilation, and mostly do not meet the minimum operation requirements of 62.2p.

Nighttime ventilation in bedrooms appears to be low for a quarter to a third of the homes in the study. This could be remedied by increased use of furnace fan controls that ensure that the furnace air handler operates a minimum number of minutes each hour. The extent to which homeowners perceive bedroom ventilation as a problem and would be willing to pay for such controls is unknown. In reports we sent to the homeowners who participated in the study, we made note of low bedroom ventilation where it occurred, and offered to provide additional information on the fan controls described above. None of the homeowners contacted us in response to raising this issue.

Although the study was not designed as a statistical comparison between Wisconsin ENERGY STAR homes and non-program new homes, it is worth noting that no large differences between program and non-program homes emerged from the study. There is good evidence that Wisconsin ENERGY STAR homes are indeed tighter than other new homes; this would be expected to result in lower natural infiltration for these homes. At the same time, these homes are probably more likely to employ central ventilation systems, which, among the homes in this study, provided demonstrably more ventilation than homes with only spot exhaust fans.

This does not necessarily mean that all program homes are adequately ventilated. The situation most at-risk for inadequate ventilation is a very tight home with a mechanical ventilation system that is unlikely to be used much. Program tracking data indicates that about nine percent of program homes fit this category if very tight is defined as less than 0.1 natural air changes per hour (based on 1/20th of the blower-door based air changes per hour at 50 Pascals) and “unlikely to be used much” is defined as spot exhaust fans.

For this study, Site G22 comes the closest to representing this type of home. Though this particular home was unusual in having one bath fan controlled by a central dehumidistat, it registered at the upper end of carbon dioxide concentration and at the lower end of air exchange based on tracer gas tests. (Of course, it was also one of the four homes monitored during warmer weather that came close to worst-case ventilation conditions).

Homes with central ventilation systems are not immune from this issue. One of the ten central systems in the study operated only as an on-demand spot exhaust during the two weeks of the study, and a second one probably would not have been operated at all except for interaction between program staff and the homeowner that came about because of participation in the study. Though we did not set out to formally assess understanding of these systems,

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it was clear to us that several homeowners did not really understand how (or when) these systems were supposed to operate.

This all leads to three recommendations for improving the program with respect to ventilation:

1. Gather additional data on actual ventilation rates in very tight program homes. This study looked at program homes in general, and did not focus on the tightest homes. Mid-winter passive tracer gas tests and carbon dioxide and humidity monitoring on a dozen or so homes deliberately selected to be very tight homes without central ventilation systems would help assess whether some program homes are too tight for the ventilation strategy used. The project could be considered a stripped down version of this study, and could re-use the same monitoring equipment.

2. Pending the results from #1, consider developing more stringent ventilation system requirements for very tight homes. “More stringent” in this case does not mean requiring more capacity, but rather requiring systems that are configured with controls that increase the likelihood that a meaningful amount of mechanical ventilation will occur in these homes. The demarcation of very tight should probably be fall somewhere between 0.05 and 0.1 natural air changes per hour. The lower value represents about four percent of program homes and 0.1 represents about 30 percent.

3. Increase program-sponsored homeowner education efforts regarding ventilation. Most participants in the program could probably use a short fact sheet that explains ventilation basics in lay terms. In addition, owners of central systems would benefit from having clearly written guidance that is as specific as possible to the equipment and controls they have in their home. Both of these efforts would benefit from being grounded in some interviews with past participants to uncover common misperceptions and questions.

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References ASHRAE. 1989. ASHRAE Standard 62-1989: Ventilation for Acceptable Indoor Air Quality, American Society of Heating, Refrigeration and Air Conditioning Engineers, Atlanta Georgia.

ASHRAE. 1993. Handbook of Fundamentals, Chapter 23, American Society of Heating, Refrigeration and Air Conditioning Engineers, Atlanta Georgia.

ASHRAE. 2002. BSR/ASHRAE Standard 62.2p Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings. Draft (third public review). American Society of Heating, Refrigeration and Air Conditioning Engineers, Atlanta Georgia, April 2002.

Carroll, Edward, Gregory Nahn, Scott Pigg, and Joseph Nagan. 2002. “Roll with the Changes: The Evolution of a Residential New Home Construction Program in Wisconsin.” In Proceedings of 2002 ACEEE Summer Study on Energy Efficiency in Buildings. Washington, D.C.: American Council for an Energy-Efficient Economy.

Dietz, Russell N., Robert W. Goodrich, Edgar A. Cote, Robert F. Wieser, 1986. "Detailed Description and Performance of a Passive Perfluorocarbon Tracer System for Building Ventilation and Air Exchange Measurements." Measured Air Leakage of Buildings. ASTM STP 904, H.R. Trechsel and P.L. Lagus, Eds., American Society for Testing and Materials, Philadelphia, pp. 203-264.

ECW. 1996. Tracking the Insulation Market for Energy Efficiency Services. Energy Center of Wisconsin Report 149-1, Energy Center of Wisconsin, Madison, Wisconsin.

Nagan, Joseph. Wisconsin Energy Star Homes Technical Director. Personal communication, October 4, 2002.

Persily, Andrew K. 1997. Evaluating Building IAQ and Ventilation with Indoor Carbon Dioxide. ASHRAE Transactions, vol. 103, pt. 2.

Pigg, Scott, and Monica Nevius. 2000. Energy and Housing in Wisconsin: A Study of Single-Family Owner-Occupied Homes. ECW Report 199-1. Madison, Wisconsin : Energy Center of Wisconsin.

Pigg, Scott. 2002. Energy Savings from the Wisconsin ENERGY STAR Homes Program, Energy Center of Wisconsin report, Madison, Wisconsin.

White, Jim H., and Mark Lawton. 1996. Ventilation in Bedrooms: A Serious Problem? Indoor Air 1996: 2:135-139.

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Appendix A

Appendix A: Additional Details

Table A1, Measured air leakage by site.

Measured @ 50 Pascals Approximate Naturala

Group Site

Home Volume

(ft3) CFM + / - ACH CFM ACH

Program D11 22,650 1442 17 3.82 67 0.18 D12 19,029 1334 33 4.21 67 0.21 D14 35,864 1532 28 2.56 101 0.17 D22 22,582 1350 14 3.59 77 0.20 D23 29,922 2609 31 5.23 139 0.28 D24 26,571 1277 11 2.88 70 0.16 F11 22,251 1067 4 2.88 44 0.12 F12 24,126 1772 4 4.41 103 0.26 F14 36,836 1017 1 1.66 43 0.07 G11 28,592 1416 7 2.97 77 0.16 G13 48,240 542 5 0.67 34 0.05 G14 50,021 1684 5 2.02 108 0.13 G22 27,667 506 2 1.10 25 0.05 G23 20,187 938 4 2.79 41 0.12 G24 20,720 926 5 2.68 37 0.11 W11 14,969 649 10 2.60 37 0.15 W12 40,818 2032 8 2.99 117 0.17 W14 32,774 862 16 1.58 66 0.12

Non-Program D13 16,672 1523 6 5.48 77 0.28 D21 39,855 2698 49 4.06 176 0.26 F13 18,851 1097 3 3.49 57 0.18 G12 34,071 1717 26 3.02 111 0.20 G21 19,533 905 3 2.78 38 0.12 W13 26,521 1866 6 4.22 93 0.21 aEstimated as 1/20th the leakage rate at 50 Pascals.

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F i e l d S t u d y o f V e n t i l a t i o n i n N e w W i s c o n s i n H o m e s

Table A2, Measured Flow rates for ventilation devices, clothes dryers and water heaters (cfm).

Bath Fans Site 1 2 3 4 5 Kitchen Range

Central System

Clothes Dryer

Water Heater

Program Homes D11 165/250 77 60 na D12 40 14 49 na/62 40 40 D14 45 42 52 51 130/170 25 na D22 35 58 140/200 70 58 D23 79 9 38 70 100/100 45 50 D24 9 13 44 255/280/290 52 na F11 142/176 97 72 38 F12 106/120 70 82 40 F14 58 74/134 54 74 G11 84 57 57 71 67 100 25 80 G13 285(v) na/158 67 na G14 52 34 31 360(v) 163 97 45 G22 34 29 91/108 75 75 G23 63 60 42 140 56 48 G24 112/140 na 72 W11 43 na/161 20 45 W12 80 100 68 23 100 na na W14 100 63/70 65 92

Non-Program Homes D13 47 45 30 45 D21 163 50 85 F13 44 46 62 na 50 G12 26 41 12 52 140/175 63 (atmos.)G21 31 36 29 na W13 64 73 46 21 115

Notes:

Italics denote flow measurement taken from previous program records rather than tests at the time of the study.

Flows for devices with multiple discrete speeds shown with slashes between speeds.

(v) designates devices with continuously variable speed; listed speed is highest possible.

“na” means no measured flow data available.

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Appendix A

Table A3, Central ventilation system descriptions.

Controls Present

Site Type of Central

System Make and Model Intermittent Operation

Spot Control Timer Dehumidistat

Furnace Blower

Interlock D11 Exhaust ducted

HRV Lifebreath 155MAX

X X

F11 Exhaust ducted HRV

Lifebreath 155MAX X X

F12 Exhaust ducted HRV

Lifebreath 155MAX X X

F14 Exhaust ducted HRV

Venmar Constructo 2.0

X X X X

G13 Exhaust ducted HRV

Venmar AVS Solo 2.0

X X X X

G14 Punch-In HRV

Venmar AVS Solo 2.0

X X

W14 Exhaust ducted HRV

Bryant VA3BAB015000

X X

D21 Exhaust ducted HRV (2 units)

Perfect Air 8100 (see note 3 below)

G23 Ducted exhaust only

Quiet Vent 4019663

X X X

G24 Ducted exhaust only

Quiet Vent 4019663

X X X

Notes:

(1) Type of System:

“Exhaust ducted HRV” refers to HRV with multi-port exhaust pickups and fresh air delivery to furnace return.

“Punch-In HRV” refers to HRV with exhaust air from furnace return and fresh air supply to furnace supply.

“Ducted exhaust only” refers to central exhaust-only system with multi-port pickups.

(2) Controls:

“Intermittent operation” means unit can operate on a fixed operation duty cycle, such as 20 minutes on, 40 minutes off.

“Spot control” refers to push buttons or crank timers in bathrooms that operate unit for a short period.

“Timer” refers to programmable time clock that can be set to operate unit at specific times of the day.

“Dehumidistat” refers to control that turns unit on at a set humidity threshold.

(3) Site D21 has two HRVs with no controls; the units run continuously.

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F i e l d S t u d y o f V e n t i l a t i o n i n N e w W i s c o n s i n H o m e s

Table A4, Occupancy, by site (based on occupancy log data).

Percent of time during monitoring period home was…

Site Normal # of occupantsa …unoccupied

…<100% of normal occupancy

…100% of normal occupancy

…>100% of normal occupancy

D11 2 18.9% 17.5% 63.6% 0.0% D12 2 18.1% 27.2% 54.4% 0.3% D13 4 14.7% 32.5% 51.1% 1.7% D14 4 5.3% 35.8% 55.3% 3.6% D21b 4 35.9% 7.3% 56.3% 0.5% D22 2 26.7% 8.9% 60.8% 3.6% D23 2 21.9% 38.1% 37.8% 2.2% D24 4 10.0% 31.1% 54.2% 4.7% F11 5 3.3% 16.1% 64.2% 16.4% F12c 5 0.6% 20.3% 40.6% 38.6% F13 2 26.1% 16.4% 56.1% 1.4% F14 4 30.8% 17.5% 51.4% 0.3% G11 4 17.5% 34.2% 47.2% 1.1% G12 4 9.4% 40.6% 46.1% 3.9% G13 2 46.7% 9.7% 41.4% 2.2% G14 4 23.3% 30.3% 45.6% 0.8% G21 4 8.3% 31.1% 51.9% 8.6% G22 4 11.7% 30.3% 56.4% 1.7% G23 4 5.6% 24.4% 53.1% 16.9% G24 4 26.4% 19.2% 46.1% 8.3% W11 2 30.0% 11.7% 58.1% 0.3% W12 4 4.2% 32.8% 62.8% 0.3% W13 6 35.6% 23.3% 38.1% 3.1% W14 5 5.6% 55.3% 37.5% 1.7%

median 4 17.8% 25.8% 52.5% 1.9% max. 6 46.7% 55.3% 64.2% 38.6% min. 2 0.6% 7.3% 37.5% 0.0%

aRepresents the number of people living in the household. bVacation period starting March 18 excluded. cHomeowner operates in-home daycare.

Page 43: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Appendix A

hour of day

D11

050

100150200

D12 D13 D14 D21

D22

050

100150200

D23 D24 F11 F12

F13

050

100150200

F14 G11 G12 G13

G14

050

100150200

G21 G22 G23 G24

0 6 12 18W11

0 6 12 180

50100150200

W12

0 6 12 18

W13

0 6 12 18

W14

0 6 12 18

Percent of normal full occupancy

hour of day

D11

050

100150200

D12 D13 D14 D21

D22

050

100150200

D23 D24 F11 F12

F13

050

100150200

F14 G11 G12 G13

G14

050

100150200

G21 G22 G23 G24

0 6 12 18W11

0 6 12 180

50100150200

W12

0 6 12 18

W13

0 6 12 18

W14

0 6 12 18

Percent of normal full occupancy

Figure A1, Average weekday occupancy profile, by site.

Page 44: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

F i e l d S t u d y o f V e n t i l a t i o n i n N e w W i s c o n s i n H o m e s

Table A5, Furnace details.

Site Make and Model Name Model Number VentingaInput

(kBtu/hr)Monitored parameterb

Mean run-time

(hours/day)D11 Trane TUX080C942CO SC 80 G 3.7 D12 Heil Quiet Comfort II PC-80 NTGM075EGA3 PV 75 I 6.5 D13 Goodman GMPN 858-3 REVB PV 60 G 6.5

D14 Bryant 355MAV060100 SC 65/100 G na D21c Loaire G9D10014UPC11A SC 65/100 G 3.0/0.4

Loaire EHHM707782 SC 39/60 G 4.0/0.5 D22 Trane XE90 TUX080C942C1 SC 80 G 2.9 D23 Carrier S8MXA100-16 SC 100 G 3.6 D24 Tempstar DC90 NTGM100EHA3 SC 100 I 2.6 F11 Armstrong na SC 50 I 3.8 F12d Armstrong GUK100D143A SC 100 I 0.7 F13 Bryant 340MAV036060 SC 60 G 2.8 F14 Bryant Plus 90i na SC 52/80 G 7.2/0.5 G11 Lennox G32Q3-75-2 SC 51/75 G 2.8/1.2 G12e Rheem RGRA-09E2AJS SC 90 G 4.1 G13 Bryant Plus 90 355MAV04060 SC 39/60 G 9.5/0.0 G14c Carrier 58MVP-08014 SC 52/80 G 1.8/3.7

Carrier 55MXA060-12 SC 60 G 1.0 G21 Trane TUX060C936C1 SC 60 G 2.3 G22 Carrier 58MXA060-12 SC 60 G 2.6 G23 Accoaire Enviro Plus 90 GNK050N12A3 SC 50 I 3.3 G24 Accoaire GNK050N12A3 SC 50 I 2.2 W11 Carrier 5600SE 58MNCA040-08 SC 40 G 5.4 W12 Carrier 58MCA120 SC 120 G 4.5 W13 Comfort Maker GNK075N14A3 SC 75 I 4.4 W14 Bryant Plus90i 355MAV042080 SC 52/80 G 4.7/0.1

Note: two figures separated by a slash represent low and high-fire stage of a two-stage furnace, respectively. aVenting codes: SC = sealed combustion; PV = power vented. bMonitored parameter refers to the furnace component used to track run-time: G = gas valve; I = inducer blower. cHome with two furnaces. dMain heating source for this home was a wood-fired furnace that was not monitored. eThis home has a three-zone distribution system.

Page 45: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Appendix A

Table A6, Passive tracer gas test results

Calculated average ventilation rate air changes per hour cfm per occupant

Site Source

location(s) Sampling tube

#1 location Sampling tube

#2 location #1 #2 #1 #2 Program Homes

D11 finished basement area

living room finished basement

area 0.17 0.14 31.4 25.7

D12 na na na na D14 living room,

kitchen kitchen master bedroom 0.07 0.09 10.4 13.8

D22 kitchen master bedroom living room 0.14 0.13 26.6 24.9 D23 living room dining room master bedroom 0.12 0.11 29.9 28.0 D24 dining room master bedroom kitchen 0.20 0.15 21.6 17.0 F11 na na na na F12 na na na na F14 na na na na G11 kitchen master bedroom living room 0.24 0.16 28.6 18.6 G13 great room master bedroom family room 0.06 0.07 25.5 27.5 G14 living room master bedroom living room 0.14 0.13 29.8 26.9 G22 kitchen living room master bedroom 0.09 0.12 10.5 13.8 G23 kitchen master bedroom living room 0.30 0.26 25.4 21.8 G24 kitchen kitchen master bedroom 0.14 0.23 11.8 19.6 W11 kitchen living room master bedroom 0.11 0.12 13.9 15.2 W12 upstairs hallway upstairs hallway kitchen 0.43 0.36 73.2 61.0 W14 na na na na

Non-Program Homes D13

kitchen kitchen finished basement

area 0.16 0.43 11.0 29.6

D21 great room (2), upstairs hallway, kitchen, finished basement area

master bedroom kitchen 0.38 0.36 63.1 59.6

F13 na na na na G12 living room master bedroom living room 0.24 0.18 33.9 25.6 G21 Kitchen Living room Master bedroom 0.10 0.13 7.8 10.9 W13 na na na na

Page 46: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

F i e l d S t u d y o f V e n t i l a t i o n i n N e w W i s c o n s i n H o m e s

Appendix B: CO2, Temperature and Humidity Plots

Feb-3 Feb-7 Feb-11 Feb-15

400

600

800

1000

1200

1400

Feb-3 Feb-7 Feb-11 Feb-15

400

600

800

1000

1200

1400

Feb-3 Feb-7 Feb-11 Feb-15

55

60

65

70

75

Feb-3 Feb-7 Feb-11 Feb-15

55

60

65

70

75

Feb-3 Feb-7 Feb-11 Feb-15

20

25

30

35

40

Feb-3 Feb-7 Feb-11 Feb-15

20

25

30

35

40

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site D11

(Note: horizontal axis tick marks correspond to midnight)

Page 47: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Feb-5 Feb-9 Feb-13 Feb-17

400

600

800

1000

1200

1400

Feb-5 Feb-9 Feb-13 Feb-17

400

600

800

1000

1200

1400

Feb-5 Feb-9 Feb-13 Feb-17

65

70

75

80

Feb-5 Feb-9 Feb-13 Feb-17

65

70

75

80

Feb-5 Feb-9 Feb-13 Feb-17

20

25

30

35

Feb-5 Feb-9 Feb-13 Feb-17

20

25

30

35

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site D12

(Note: horizontal axis tick marks correspond to midnight)

Page 48: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Feb-5 Feb-9 Feb-13 Feb-17

200400600800

100012001400160018002000

Feb-5 Feb-9 Feb-13 Feb-17

200400600800

100012001400160018002000

Feb-5 Feb-9 Feb-13 Feb-17

55

60

65

70

75

80

Feb-5 Feb-9 Feb-13 Feb-17

55

60

65

70

75

80

Feb-5 Feb-9 Feb-13 Feb-17

20

25

30

35

40

Feb-5 Feb-9 Feb-13 Feb-17

20

25

30

35

40

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site D13

(Note: horizontal axis tick marks correspond to midnight)

Page 49: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Feb-6 Feb-10 Feb-14 Feb-18

400

600

800

1000

1200

1400

1600

Feb-6Feb-10Feb-14Feb-18

400600800

1000120014001600

Feb-6 Feb-10 Feb-14 Feb-18

60

65

70

75

Feb-6Feb-10Feb-14Feb-18

60657075

Feb-6 Feb-10 Feb-14 Feb-18

25

30

35

40

Feb-6Feb-10Feb-14Feb-18

25

30

35

40

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site D14

(Note: horizontal axis tick marks correspond to midnight)

Page 50: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-10 Mar-14 Mar-18 Mar-22 Mar-26

200

400

600

800

Mar-10 Mar-14 Mar-18 Mar-22 Mar-26

200

400

600

800

Mar-10 Mar-14 Mar-18 Mar-22 Mar-26

60

65

70

75

Mar-10 Mar-14 Mar-18 Mar-22 Mar-26

60

65

70

75

Mar-10 Mar-14 Mar-18 Mar-22 Mar-26

25

30

35

40

45

50

Mar-10 Mar-14 Mar-18 Mar-22 Mar-26

25

30

35

40

45

50

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site D21

(Note: horizontal axis tick marks correspond to midnight)

Page 51: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-10 Mar-14 Mar-18 Mar-22

400

600

800

1000

1200

Mar-10 Mar-14 Mar-18 Mar-22

400

600

800

1000

1200

Mar-10 Mar-14 Mar-18 Mar-22

60

65

70

75

Mar-10 Mar-14 Mar-18 Mar-22

60

65

70

75

Mar-10 Mar-14 Mar-18 Mar-22

25

30

35

40

Mar-10 Mar-14 Mar-18 Mar-22

25

30

35

40

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site D22

(Note: horizontal axis tick marks correspond to midnight)

Page 52: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-8 Mar-12 Mar-16 Mar-20

400

600

800

1000

1200

1400

1600

1800

Mar-8 Mar-12 Mar-16 Mar-20

400

600

800

1000

1200

1400

1600

1800

Mar-8 Mar-12 Mar-16 Mar-20

60

65

70

75

80

Mar-8 Mar-12 Mar-16 Mar-20

60

65

70

75

80

Mar-8 Mar-12 Mar-16 Mar-20

25

30

35

40

45

50

Mar-8 Mar-12 Mar-16 Mar-20

25

30

35

40

45

50

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site D23

(Note: horizontal axis tick marks correspond to midnight)

Page 53: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-8 Mar-12 Mar-16 Mar-20

600

800

1000

1200

1400

1600

1800

Mar-8 Mar-12 Mar-16 Mar-20

600

800

1000

1200

1400

1600

1800

Mar-8 Mar-12 Mar-16 Mar-20

60

65

70

75

Mar-8 Mar-12 Mar-16 Mar-20

60

65

70

75

Mar-8 Mar-12 Mar-16 Mar-20

25

30

35

40

Mar-8 Mar-12 Mar-16 Mar-20

25

30

35

40

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site D24

(Note: horizontal axis tick marks correspond to midnight)

Page 54: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-20 Mar-24 Mar-28 Apr-1 Apr-5

400

600

800

1000

1200

1400

1600

Mar-20 Mar-24 Mar-28 Apr-1 Apr-5

400

600

800

1000

1200

1400

1600

Mar-20 Mar-24 Mar-28 Apr-1 Apr-5

65

70

75

80

85

Mar-20 Mar-24 Mar-28 Apr-1 Apr-5

65

70

75

80

85

Mar-20 Mar-24 Mar-28 Apr-1 Apr-5

20

25

30

35

40

45

Mar-20 Mar-24 Mar-28 Apr-1 Apr-5

20

25

30

35

40

45

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site F11

(Note: horizontal axis tick marks correspond to midnight)

Page 55: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-20 Mar-24 Mar-28 Apr-1 Apr-5

400600800

100012001400160018002000

Mar-20 Mar-24 Mar-28 Apr-1 Apr-5

400600800

100012001400160018002000

Mar-20 Mar-24 Mar-28 Apr-1 Apr-5

50

55

60

65

70

75

Mar-20 Mar-24 Mar-28 Apr-1 Apr-5

50

55

60

65

70

75

Mar-20 Mar-24 Mar-28 Apr-1 Apr-5

25

30

35

40

45

50

55

Mar-20 Mar-24 Mar-28 Apr-1 Apr-5

25

30

35

40

45

50

55

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site F12

(Note: horizontal axis tick marks correspond to midnight)

Page 56: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-21 Mar-25 Mar-29 Apr-2

400

600

800

1000

1200

1400

1600

Mar-21 Mar-25 Mar-29 Apr-2

400

600

800

1000

1200

1400

1600

Mar-21 Mar-25 Mar-29 Apr-2

60

65

70

75

Mar-21 Mar-25 Mar-29 Apr-2

60

65

70

75

Mar-21 Mar-25 Mar-29 Apr-2

20

25

30

35

40

45

50

Mar-21 Mar-25 Mar-29 Apr-2

20

25

30

35

40

45

50

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site F13

(Note: horizontal axis tick marks correspond to midnight)

Page 57: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-21 Mar-25 Mar-29 Apr-2

400

600

800

1000

1200

1400

Mar-21 Mar-25 Mar-29 Apr-2

400

600

800

1000

1200

1400

Mar-21 Mar-25 Mar-29 Apr-2

60

65

70

75

Mar-21 Mar-25 Mar-29 Apr-2

60

65

70

75

Mar-21 Mar-25 Mar-29 Apr-2

25

30

35

40

45

Mar-21 Mar-25 Mar-29 Apr-2

25

30

35

40

45

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site F14

(Note: horizontal axis tick marks correspond to midnight)

Page 58: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-3 Mar-7 Mar-11 Mar-15

400

600

800

1000

1200

1400

1600

Mar-3 Mar-7 Mar-11 Mar-15

400

600

800

1000

1200

1400

1600

Mar-3 Mar-7 Mar-11 Mar-15

60

65

70

Mar-3 Mar-7 Mar-11 Mar-15

60

65

70

Mar-3 Mar-7 Mar-11 Mar-15

25

30

35

40

45

50

55

60

Mar-3 Mar-7 Mar-11 Mar-15

25

30

35

40

45

50

55

60

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site G11

(Note: horizontal axis tick marks correspond to midnight)

Page 59: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-3 Mar-7 Mar-11 Mar-15

400

600

800

1000

1200

1400

1600

Mar-3 Mar-7 Mar-11 Mar-15

400

600

800

1000

1200

1400

1600

Mar-3 Mar-7 Mar-11 Mar-15

65

70

75

80

Mar-3 Mar-7 Mar-11 Mar-15

65

70

75

80

Mar-3 Mar-7 Mar-11 Mar-15

25

30

35

40

45

50

Mar-3 Mar-7 Mar-11 Mar-15

25

30

35

40

45

50

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site G12

(Note: horizontal axis tick marks correspond to midnight)

Page 60: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-2 Mar-6 Mar-10 Mar-14

400

600

800

1000

1200

1400

1600

1800

Mar-2 Mar-6 Mar-10 Mar-14

400

600

800

1000

1200

1400

1600

1800

Mar-2 Mar-6 Mar-10 Mar-14

65

70

75

Mar-2 Mar-6 Mar-10 Mar-14

65

70

75

Mar-2 Mar-6 Mar-10 Mar-14

25

30

35

40

45

Mar-2 Mar-6 Mar-10 Mar-14

25

30

35

40

45

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site G13

(Note: horizontal axis tick marks correspond to midnight)

Page 61: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-3Mar-7Mar-11Mar-15

0

200

400

600

800

1000

1200

Mar-3 Mar-7 Mar-11 Mar-15

0

200

400

600

800

1000

1200

Mar-3 Mar-7 Mar-11 Mar-15

60

65

70

75

Mar-3 Mar-7 Mar-11 Mar-15

60

65

70

75

Mar-3 Mar-7 Mar-11 Mar-15

25

30

35

40

45

Mar-3 Mar-7 Mar-11 Mar-15

25

30

35

40

45

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site G14

(Note: horizontal axis tick marks correspond to midnight)

Page 62: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-29 Apr-2 Apr-6 Apr-10

400600800

100012001400160018002000220024002600

Mar-29 Apr-2 Apr-6 Apr-10

400600800

100012001400160018002000220024002600

Mar-29 Apr-2 Apr-6 Apr-10

55

60

65

70

75

Mar-29 Apr-2 Apr-6 Apr-10

55

60

65

70

75

Mar-29 Apr-2 Apr-6 Apr-10

35

40

45

50

55

60

Mar-29 Apr-2 Apr-6 Apr-10

35

40

45

50

55

60

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site G21

(Note: horizontal axis tick marks correspond to midnight)

Page 63: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-29 Apr-2 Apr-6 Apr-10

600800

1000120014001600180020002200

Mar-29 Apr-2 Apr-6 Apr-10

600800

1000120014001600180020002200

Mar-29 Apr-2 Apr-6 Apr-10

60

65

70

75

Mar-29 Apr-2 Apr-6 Apr-10

60

65

70

75

Mar-29 Apr-2 Apr-6 Apr-10

35

40

45

50

55

Mar-29 Apr-2 Apr-6 Apr-10

35

40

45

50

55

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site G22

(Note: horizontal axis tick marks correspond to midnight)

Page 64: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-30 Apr-3 Apr-7 Apr-11

200400600800

10001200140016001800200022002400

Mar-30 Apr-3 Apr-7 Apr-11

200400600800

10001200140016001800200022002400

Mar-30 Apr-3 Apr-7 Apr-11

65

70

75

80

Mar-30 Apr-3 Apr-7 Apr-11

65

70

75

80

Mar-30 Apr-3 Apr-7 Apr-11

30

35

40

45

50

Mar-30 Apr-3 Apr-7 Apr-11

30

35

40

45

50

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site G23

(Note: horizontal axis tick marks correspond to midnight)

Page 65: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Mar-30 Apr-3 Apr-7 Apr-11

200400600800

100012001400160018002000220024002600

Mar-30 Apr-3 Apr-7 Apr-11

200400600800

100012001400160018002000220024002600

Mar-30 Apr-3 Apr-7 Apr-11

60

65

70

75

Mar-30 Apr-3 Apr-7 Apr-11

60

65

70

75

Mar-30 Apr-3 Apr-7 Apr-11

30

35

40

45

50

55

Mar-30 Apr-3 Apr-7 Apr-11

30

35

40

45

50

55

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site G24

(Note: horizontal axis tick marks correspond to midnight)

Page 66: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Feb-16 Feb-20 Feb-24 Feb-28 Mar-4

400600800

10001200140016001800200022002400

Feb-16 Feb-20 Feb-24 Feb-28 Mar-4

400600800

10001200140016001800200022002400

Feb-16 Feb-20 Feb-24 Feb-28 Mar-4

60

65

70

75

80

Feb-16 Feb-20 Feb-24 Feb-28 Mar-4

60

65

70

75

80

Feb-16 Feb-20 Feb-24 Feb-28 Mar-4

25

30

35

40

45

50

55

60

Feb-16 Feb-20 Feb-24 Feb-28 Mar-4

25

30

35

40

45

50

55

60

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site W11

(Note: horizontal axis tick marks correspond to midnight)

Page 67: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Feb-18 Feb-22 Feb-26 Mar-2

200400600800

100012001400160018002000

Feb-18 Feb-22 Feb-26 Mar-2

200400600800

100012001400160018002000

Feb-18 Feb-22 Feb-26 Mar-2

65

70

75

80

Feb-18 Feb-22 Feb-26 Mar-2

65

70

75

80

Feb-18 Feb-22 Feb-26 Mar-2

20

25

30

35

40

Feb-18 Feb-22 Feb-26 Mar-2

20

25

30

35

40

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site W12

(Note: horizontal axis tick marks correspond to midnight)

Page 68: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Feb-18 Feb-22 Feb-26 Mar-2

400

600

800

1000

1200

1400

Feb-18 Feb-22 Feb-26 Mar-2

400

600

800

1000

1200

1400

Feb-18 Feb-22 Feb-26 Mar-2

60

65

70

75

Feb-18 Feb-22 Feb-26 Mar-2

60

65

70

75

Feb-18 Feb-22 Feb-26 Mar-2

20

25

30

35

40

45

50

55

Feb-18 Feb-22 Feb-26 Mar-2

20

25

30

35

40

45

50

55

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site W13

(Note: horizontal axis tick marks correspond to midnight)

Page 69: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

Feb-19 Feb-23 Feb-27 Mar-3

400

600

800

1000

1200

1400

1600

1800

Feb-19 Feb-23 Feb-27 Mar-3

400

600

800

1000

1200

1400

1600

1800

Feb-19 Feb-23 Feb-27 Mar-3

55

60

65

70

75

Feb-19 Feb-23 Feb-27 Mar-3

55

60

65

70

75

Feb-19 Feb-23 Feb-27 Mar-3

25

30

35

40

45

50

Feb-19 Feb-23 Feb-27 Mar-3

25

30

35

40

45

50

CO

2 C

once

ntra

tion

(ppm

) T

empe

ratu

re (F

) R

elat

ive

Hum

idity

(%)

Living Room Master Bedroom Site W14

(Note: horizontal axis tick marks correspond to midnight)

Page 70: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report
Andrea
Appendix C: Occupancy Log (sample)
Andrea
Andrea
Occupancy Log Instructions
Andrea
C-1
Page 71: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report
Andrea
C-2
Andrea
A p p e n d i x C
Page 72: Life-Cycle Energy Costs and Greenhouse Gas … Energy Costs and Greenhouse Gas Emissions for Gas Turbine Power April, 2002 report report report report report report report report report

ENERGY CENTEROF WISCONSIN

595 Science Drive

Madison, WI 53711

Phone: 608.238.4601

Fax: 608.238.8733

Email: [email protected]

www.ecw.org

Printed on Plainfield Plus,

a recycled chlorine-free stock

containing 20% post-consumer waste.