Griffolyn® roof vapor retarders are available in stock sizes and can be manufactured to custom sizes. Send us your product specs today!
A vapor barrier reduces the movement of water vapor by diffusion. Holes in the vapor barrier that allow humid air through may allow a lot more water vapor into an assembly than the vapor barrier is stopping. Because of this,air sealing is more important than vapor retarders. If you’re ...
Deciding to use a vapor barrier on a building's interior or exterior depends on theclimate zone. For example, the 2021 International Building Code (IBC)1404.3and the 2021 International Residential Code(IRC)R702.7instruct Class I or II vapor barriers and retarders inside frame walls inclimate zon...
Answer: A widely accepted rule of thumb holds that the building's exterior wall surface should be 5 to 10 times as moisture-permeable as the interior vapor retarder installed on the inside surface of the building's exterior walls. ("Retarder" not "barrier" is ASHRAE's preferred term). Howe...