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Residential Ventilation & IAQ Requirements for Existing Homes: Second Discussion Proposed Specification Outline Regional Technical Forum November 9 th,

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Presentation on theme: "Residential Ventilation & IAQ Requirements for Existing Homes: Second Discussion Proposed Specification Outline Regional Technical Forum November 9 th,"— Presentation transcript:

1 Residential Ventilation & IAQ Requirements for Existing Homes: Second Discussion Proposed Specification Outline Regional Technical Forum November 9 th, 2009

2 Proposed IAQ Specification Summary; actual spec language to be developed after adoption of basic idea (Items in red to be added to the specs in 3 years, items in blue need an RTF decision) 1.The RTF IAQ standard must be met where any of the following measures take place: a)Air-sealing b)Duct sealing c)Window replacement d)Wall insulation e)Attic Insulation f)Floor Insulation 2.Homeowner shall be given information on indoor air quality and their ventilation system. 3.House is not eligible to receive the measures identified in Section 1 if either of the following are true: a)An unvented combustion appliance is located inside the house; or b)There are obvious signs of moisture problems (mold). 4.A CO alarm that is listed with the Canadian Standards Association is required in homes where a combustion appliance is present. 5.Where duct systems are located outside heated space, ducts shall be PTCS certified. 6.Blower door shall be used to determine both pre- and post- whole house leakage levels. 7.A whole-house mechanical ventilation system that meets the calculator shall be installed. Options on the calculator’s underlying ventilation rate: a)Follow 62.2; or b)Whole-house ventilation not required, unless blower door test results in 0.40 ACHn or less, then 62.2. 8.Ten percent (10%) of all homes that receive the measures in Section 1 must receive an on-site 3 rd -party inspection to verify all IAQ requirements are met. 2

3 We are not Crazy Design Goals: – To achieve more energy savings per home and minimize negative IAQ impacts. – Eliminate the “stick a fan in it” as the lowest cost solution Acknowledgements: – This is not the perfect solution. The perfect solution is a ERV or HRV with a distributed supply and return system. Its perfect, but too expensive $3,000 to $4,000 – This will require time and money to implement. 3

4 Discussion of Each Proposed Spec Discussion Air-sealing and duct sealing directly reduce natural air-infiltration – Contractors are already familiar with following an IAQ standard and using testing equipment – Contractors would need training on the revised specification All weatherization measures can (and should) reduce natural air-infiltration. – It will take time (3 years?) to set up the training (blower door testing, etc.) and quality assurance processes for the measures in red. – Without testing, there’s no way to tell how how much the measure changed the natural infiltration rates of these homes. It could be a lot, or not. 4 Proposed Spec 1.The RTF IAQ standard must be met where any of the following measures take place: a)Air-sealing b)Duct sealing c)Window replacement d)Wall insulation e)Attic Insulation f)Floor Insulation

5 Discussion of Each Proposed Spec Discussion This complies with: – ASHRAE 62.2, – BPA Record of Decisions, and – common sense. 5 Proposed Spec 2.Homeowner shall be given information on indoor air quality and their ventilation system.

6 Discussion of Each Proposed Spec Discussion ASHRAE 62.2 does not fix these issues; they need to be dealt with separately. 6 Proposed Spec 3.House is not eligible to receive the measures identified in Section 1 if either of the following are true: a)An unvented combustion appliance is located inside the house; or b)There are obvious signs of moisture problems (mold).

7 Discussion of Each Proposed Spec Discussion Carbon monoxide poisoning is one of the most likely causes of (quick) death related to IAQ. ASHRAE 62.2 may soon require a CO alarm on all houses. 7 Proposed Spec 4.A CO alarm that is listed with the Canadian Standards Association is required in homes where a combustion appliance is present.

8 Discussion of Each Proposed Spec Discussion Leaky duct systems can cause “dirty” air from the garage, attic, or crawlspace to be brought into the house. ASHRAE 62.2 currently requires tight ducts when ducts are located in the garage. – A proposed spec may change this to be required anytime ducts are outside. 8 Proposed Spec 5.Where duct systems are located outside heated space, ducts shall be PTCS certified.

9 Discussion of Each Proposed Spec Discussion More Energy Savings: – This spec allows and encourages energy savings credit to be taken for infiltration reductions for all measures. – Post-blower door test is required in order to take ASHRAE 62.2’s infiltration credit Without a blower door test, ASHRAE 62.2 ventilation rates can be quite high (for tight houses), wasting energy with unnecessary ventilation. 9 Proposed Spec 6.Blower door shall be used to determine both pre- and post- whole house leakage levels.

10 Discussion of Each Proposed Spec Discussion RTF needs to make a decision on this. – Following 62.2 would mean: A fan is required in most cases – More Cost, More Training – More Air-Sealing (= more measures and more savings?) » Air-sealing crews can seal houses tighter; » Air-sealing crews may be brought in more often on other measures RTF can stand behind ASHRAE’s national standard – Having a 0.40 ACHn threshold would mean: A fan can be avoided – Less Cost (= more measures?) – Less Ventilation (= more savings?) Less Air-Sealing RTF would need to justify its own standard 10 Proposed Spec 7.A whole-house mechanical ventilation system that meets the calculator shall be installed. Options on the calculator’s underlying ventilation rate: a)Follow 62.2; or b)Whole-house ventilation not required, unless blower door test results in 0.40 ACHn or less, then 62.2.

11 Discussion of Each Proposed Spec Discussion New specifications are adhered to better with good follow- up/oversight. – Especially specs that require the use of testing equipment. 11 Proposed Spec 8.Ten percent (10%) of all homes that receive the measures in Section 1 must receive an on- site 3 rd -party inspection to verify all IAQ requirements are met.

12 A Look at Savings and Cost-Effectiveness Method & Assumptions: SEEM modeling, Portland, 1800 ft 2, 1-story, crawlspace, last- measure-in Caveats: – Ventilation fan energy not taken into account – Analysis assumes a linear relationship between infiltration energy use and outdoor temperature Increased stack effect (i.e. increased infiltration and energy) at low outdoor temps not taken into account – This analysis is a simplified version of RTF savings calculations and is intended to compare costs and cost-effectiveness of various measures, it is NOT INTENDED TO REPRESENT SAVINGS NOR B/C RATIOS FOR THE DESCRIBED MEASURES. 12 Results – Standalone Measures

13 A Look at Savings and Cost-Effectiveness (continued) 13 Results – Install Measure in Conjunction with Air Sealing (0.60 ACHn to 0.40 ACHn) Results – Install Measure in Conjunction with Air Sealing, but don’t stop at 0.40 (0.60 to 0.30 ACHn) Results – Install Measure, Air Seal, with Ventilation System Cost

14 14 A (graphical) Look at Savings and Cost-Effectiveness (continued)

15 Estimated Start-up Costs 15 Assumptions # of contractors200 Cost for TestingEquipment$2,500 Required Trainings50 Cost Per Training$2,500 Costs Training Costs$125,000 Utility Meetings$50,000 Training Materials$50,000 Equipment Costs$500,000 QA /Year$680,000 TOTAL$1,405,000

16 What We Need from the RTF Ultimately – An RTF decision on an IAQ standard Today – Discussion – Guidance for the Subcommittee Proposed Specification: – Overall is it on the right track? – Leanings regarding specification #7? A vote? What else could the subcommittee do to help with a decision? 16

17 END 17

18 Slides from Oct 13 th, 2009 RTF Meeting 18

19 History - BPA 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 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 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 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 19

20 Current RTF IAQ Requirements Summary 20

21 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. 21

22 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 26 th ) 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 22

23 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/100ft 2 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 23

24 24

25 ASHRAE 62.2 – Example Home #125 Note: Current RTF standard for manufactured homes is always required and independent of ACHn.

26 ASHRAE 62.2 – Example Home #226 Note: Current RTF standard for manufactured homes is always required and independent of ACHn.

27 ASHRAE 62.2 – Example Home #3 27 Note: Current RTF standard for manufactured homes is always required and independent of ACHn.

28 ASHRAE 62.2 – Example Home #4 28 Note: Current RTF standard for manufactured homes is always required and independent of ACHn.

29 Which Efficiency Measures Should Apply? The subcommittee tentatively has agreed that everything except heat pumps should receive some kind of IAQ attention. 29

30 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? 30

31 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 ???? 31

32 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: 1.Have subcommittee incorporate 62.2 into measure specifications, also set up quality assurance plan & requirements; 2.Keep specs as they are; 3.Pass this IAQ job on to someone else (BPA?, codes?); 4.Suggest, but don’t require: Rely on letting the (informed) homeowner make the decision about what IAQ strategies to employ. 32


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