Residential Ventilation

1
Residential Ventilation IAQ Requirements for
Existing HomesSecond Discussion

• Proposed Specification Outline
• Regional Technical Forum
• November 9th, 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)
•  
• The RTF IAQ standard must be met where any of the
  following measures take place
• Air-sealing
• Duct sealing
• Window replacement
• Wall insulation
• Attic Insulation
• Floor Insulation
• Homeowner shall be given information on indoor
  air quality and their ventilation system.
• House is not eligible to receive the measures
  identified in Section 1 if either of the
  following are true
• An unvented combustion appliance is located
  inside the house or
• There are obvious signs of moisture problems
  (mold).
• A CO alarm that is listed with the Canadian
  Standards Association is required in homes where
  a combustion appliance is present.
• Where duct systems are located outside heated
  space, ducts shall be PTCS certified.

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.

4
Discussion of Each Proposed Spec

• Proposed Spec
•  
• The RTF IAQ standard must be met where any of the
  following measures take place
• Air-sealing
• Duct sealing
• Window replacement
• Wall insulation
• Attic Insulation
• Floor Insulation

• 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, theres no way to tell how how
  much the measure changed the natural infiltration
  rates of these homes. It could be a lot, or not.

5
Discussion of Each Proposed Spec

• Proposed Spec
•  
• Homeowner shall be given information on indoor
  air quality and their ventilation system.

• Discussion
• This complies with
• ASHRAE 62.2,
• BPA Record of Decisions, and
• common sense.

6
Discussion of Each Proposed Spec

• Proposed Spec
• House is not eligible to receive the measures
  identified in Section 1 if either of the
  following are true
• An unvented combustion appliance is located
  inside the house or
• There are obvious signs of moisture problems
  (mold).

• Discussion
• ASHRAE 62.2 does not fix these issues they need
  to be dealt with separately.

7
Discussion of Each Proposed Spec

• Proposed Spec
• A CO alarm that is listed with the Canadian
  Standards Association is required in homes where
  a combustion appliance is present.

• 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.

8
Discussion of Each Proposed Spec

• Proposed Spec
• Where duct systems are located outside heated
  space, ducts shall be PTCS certified.

• 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.

9
Discussion of Each Proposed Spec

• Proposed Spec
• Blower door shall be used to determine both pre-
  and post- whole house leakage levels.

• 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 62.2s infiltration credit
• Without a blower door test, ASHRAE 62.2
  ventilation rates can be quite high (for tight
  houses), wasting energy with unnecessary
  ventilation.

10
Discussion of Each Proposed Spec

• Proposed Spec
• A whole-house mechanical ventilation system that
  meets the calculator shall be installed. Options
  on the calculators underlying ventilation rate
  
• Follow 62.2 or
• Whole-house ventilation not required, unless
  blower door test results in 0.40 ACHn or less,
  then 62.2.

• 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 ASHRAEs 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

11
Discussion of Each Proposed Spec

• Proposed Spec
• Ten percent (10) of all homes that receive the
  measures in Section 1 must receive an on-site
  3rd-party inspection to verify all IAQ
  requirements are met.

• Discussion
• New specifications are adhered to better with
  good follow-up/oversight.
• Especially specs that require the use of testing
  equipment.

12
A Look at Savings and Cost-Effectiveness

• Method Assumptions SEEM modeling, Portland,
  1800 ft2, 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.

Results Standalone Measures
13
A Look at Savings and Cost-Effectiveness
(continued)
Results Install Measure in Conjunction with Air
Sealing (0.60 ACHn to 0.40 ACHn)
Results Install Measure in Conjunction with Air
Sealing , but dont stop at 0.40 (0.60 to 0.30
ACHn)
Results Install Measure, Air Seal, with
Ventilation System Cost
14
A (graphical) Look at Savings and
Cost-Effectiveness (continued)
15
Estimated Start-up Costs
Assumptions Assumptions
of contractors 200
Cost for TestingEquipment 2,500
Required Trainings 50
Cost Per Training 2,500

Costs 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?

17
END
18
Slides from Oct 13th, 2009 RTF Meeting
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

• 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

• 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 dont
• Manufactured Homes
• All measures require whole house ventilation
• New Homes all require whole house ventilation

• 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 RODs should be followed
• Also, manufactured homes may be allowed, if they
  follow the new homes ROD (1989).
• Theyre subject to more stringent requirements
  because insulating manufactured homes is believed
  to decrease natural infiltration more than
  insulating site built homes

20
Current RTF IAQ Requirements Summary
21
What Is 62.2? (From ASHRAEs 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.

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 gt
  15cfm/100 square feet of floor area.
• Total duct leakage must be lt 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)

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/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

24
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25
ASHRAE 62.2 Example Home 1

• Note Current RTF standard for manufactured homes
  is always required and independent of ACHn.

26
ASHRAE 62.2 Example Home 2
Note Current RTF standard for manufactured homes
is always required and independent of ACHn.
27
ASHRAE 62.2 Example Home 3
Note Current RTF standard for manufactured homes
is always required and independent of ACHn.
28
ASHRAE 62.2 Example Home 4
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.

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?

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
• ????

32
Discussion RTFs 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?
• Its one thing to have a spec, but how should IAQ
  requirements be verified? IAQ doesnt 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 dont require Rely on letting the
  (informed) homeowner make the decision about what
  IAQ strategies to employ.