Window Opening Is No Longer an Option; Garage Air Barrier Requirements Tightened.

ATLANTA, GA — The American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) has published four amendments to its standard for residential ventilation, Standard 62.2. The latest version of the standard, “2008 Supplement to Standard 62.2-2007,” includes addenda with the following changes:

* Standard 62.2 no longer allows homes in mild climates to omit mechanical ventilation. A former provision omitted requirements for mechanical ventilation for homes in mild climates, based on an assumption that homeowners in mild climates usually open windows when necessary. However, recent California research suggests that few homeowners actually open windows, so the exception for mild climates has been eliminated.

* Homes with attached garages must comply with new air-sealing requirements to prevent infiltration of contaminants from the garage to the home. The addendum directs builders to “Air seal walls, ceilings, and floors that separate garages from occupiable space. To be considered air sealed, all joints, seams, penetrations, openings between door assemblies and their respective jambs and framing, and other sources of air leakage through wall and ceiling assemblies separating the garage from the residence and its attic area shall be caulked, gasketed, weatherstripped, wrapped, or otherwise sealed to limit air movement.”

For more information, visit www.ashrae.org/technology/page/132.