Residential Ventilation & IAQ Requirements for Existing Homes

1. Residential Ventilation & IAQ Requirements for Existing Homes History, ASHRAE 62.2, and the RTF’s Role Regional Technical Forum October 13th, 2009

2. History - BPA • 1984 • “Expanded Residential Weatherization Program” RECORD OF DECISION allows house tightening measures (storm windows, wall insulation, weatherstripping, door treatments, etc.) if: • Homeowner receives information on IAQ and how to reduce pollutants • Radon monitoring is provided to homeowners • Homes with tested high radon levels receive subsidy for mitigation • Concerns: Primarily Radon 1981 • Residential Weatherization Program allows air tightening measures if home: • is site built • has ventilated crawlspace • Does not have wood stove, foam insulation (formaldehyde), nor unvented combustion appliances • IAQ brochures given to homeowners • Concerns: Radon, combustion byproducts, formaldehyde • 1989 • “New Energy-Efficient Homes Program” RECORD OF DECISION requires: • Exhaust fans in kitchens and baths • Whole House mechanical ventilation • Designated air supplies for combustion appliances • IAQ information given to homeowner • Building materials that meet HUD standards for formaldehyde emissions • Attention to radon and mitigation as necessary • Concerns: Radon and other indoor pollutants • 1993 • “Resource Programs” RECORD OF DECISION says: • Radon no longer an issue for either new home efficiency programs nor existing home weatherization programs • Otherwise, 1984 and 1989 ROD’s should be followed • Also, manufactured homes may be allowed, if they follow the new homes ROD (1989). • They’re subject to more stringent requirements because insulating manufactured homes is believed to decrease natural infiltration more than insulating site built homes • Today • Site Built • Some air sealing measures require whole house ventilation • Other Wx measures don’t • Manufactured Homes • All measures require whole house ventilation • New Homes all require whole house ventilation

3. Current RTF IAQ Requirements Summary

4. What Is 62.2? (From ASHRAE’s Website) ANSI/ASHRAE 62.2-2007 – Published standard. (Supersedes ANSI/ASHRAE 62.2-2004.) Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings 1. PURPOSE: This standard defines the roles of and minimum requirements for mechanical and natural ventilation systems and the building envelope intended to provide acceptable indoor air quality in low-rise residential buildings. 2. SCOPE: This standard applies to spaces intended for human occupancy within single-family houses and multifamily structures of three stories or fewer above grade, including manufactured and modular houses. This standard does not apply to transient housing such as hotels, motels, nursing homes, dormitories, or jails. 2.1 This standard considers chemical, physical, and biological contaminants that can affect air quality. Thermal comfort requirements are not included in this standard (see ANSI/ASHRAE Standard 55-2004, Thermal Environmental Conditions for Human Occupancy). 2.2 While acceptable indoor air quality is the goal of this standard, it will not necessarily be achieved even if all requirements are met: a) because of the diversity of sources and contaminants in indoor air and the range of susceptibility in the population; b) because of the many other factors that may affect occupant perception and acceptance of indoor air quality, such as air temperature, humidity, noise, lighting, and psychological stress; c) if the ambient air is unacceptable and this air is brought into the building without first being cleaned (cleaning of ambient outdoor air is not required by this standard.); d) if the system(s) are not operated and maintained as designed, or e) when high-polluting events occur.  2.3 This standard does not address unvented combustion space heaters.

5. ASHRAE 62.2 – Basic Components • Whole Building Mechanical Ventilation System • Required CFM = 0.01 x Floor Area + 7.5 x [(Number of Bedrooms)+1] Note: adjustments are made for high occupant density and intermittent operation • Local Mechanical Exhaust • Kitchens = 100 cfm • Bathrooms = 50 cfm (Note: Continuous operation also allowed at different rates) • Other Requirements • Prescriptively seal house between attic, crawl, garage • Provide ventilation system instructions to homeowner • Combustion appliances • receive adequate combustion air • where atmospherically vented appliances are inside occupiable space, additional requirements if two largest exhaust fans have flow rate > 15cfm/100 square feet of floor area. • Total duct leakage must be < 6% of total fan flow at 25 Pa if ducts are located in the garage. • PROPOSED SPEC: Required anywhere ducts are located outside the pressure boundary. • Rooms must have ventilation openings (i.e. openable window area) of 4% of floor area or greater. (exceptions) • Filtration requirements for systems that use ducts • PROPOSED SPEC: CO alarm required (Out for public comment until Oct 26th) • Equipment Requirements • Tested and rated for flow and sound according to HVI • Sound ratings: Continuous fans < 1 sone; Intermitent Fans < 3 sones • Use tested airflow; or use airflow rating at 0.25 in H20 with proper duct design

6. ASHRAE 62.2 – Existing Home Exceptions • Inadequate Existing Bath/Kitchen Fans • An increase in whole-house ventilation rates can be used to overcome a deficiency in existing bath/kitchen fan flow rates. • Infiltration Credit • Existing homes with an effective infiltration rate greater than 2cfm/100ft2 may use a portion of this “excess” infiltration to reduce the required whole house ventilation rate. Effective Infiltration is estimated based on: • House tightness (blower door test) • Climate • Building height

8. ASHRAE 62.2 – Example Home #1 Note: Current RTF standard for manufactured homes is always required and independent of ACHn.

9. ASHRAE 62.2 – Example Home #2 Note: Current RTF standard for manufactured homes is always required and independent of ACHn.

10. ASHRAE 62.2 – Example Home #3 Note: Current RTF standard for manufactured homes is always required and independent of ACHn.

11. ASHRAE 62.2 – Example Home #4 Note: Current RTF standard for manufactured homes is always required and independent of ACHn.

12. Which Efficiency Measures Should Apply? The subcommittee tentatively has agreed that everything except heat pumps should receive some kind of IAQ attention.

13. What do Others Require? • ASHRAE 62.2 • Wisconsin • California • Others? • Older Versions of ASHRAE (62-2001) • At least 0.35 ACH and 15 CFM per person • Low Income Weatherization Programs • Others?

14. What might it look like to implement ASHRAE 62.2 for Wx Programs? • Ventilation Rate Calculator • Increased Costs • Blower Door Test • Exhaust Fan Flow Tests • Whole House Fan & Controller Installation • CO Alarm (?) • Training (LOTS of training) • Oversight/Verification • Incorporate ASHRAE 62.2 updates ????

15. Discussion: RTF’s Role and Issues • Does the RTF have adequate expertise in IAQ? If not, then who? • If we attempt to follow 62.2: • Can we get “close enough” on some requirements and are there some we can ignore? • For which measures should 62.2 be required? • Should there be differences for single family, multifamily, or manufactured homes? • It’s one thing to have a spec, but how should IAQ requirements be verified? IAQ doesn’t save energy; will it receive attention? • Will the added cost/burden put a stop to Wx programs? • What about new construction? Potential Options: • Have subcommittee incorporate 62.2 into measure specifications, also set up quality assurance plan & requirements; • Keep specs as they are; • Pass this IAQ job on to someone else (BPA?, codes?); • Suggest, but don’t require: Rely on letting the (informed) homeowner make the decision about what IAQ strategies to employ.