Air barrier for existing masonry party wall?
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Hi. I’m wondering if anyone has any experience with spray-applied air barriers for existing masonry party walls.
I’m in Philly designing Passivehouse infills and we need a way to continuously air seal the face of adjacent brick party walls to maintain our envelope. We usually use closed cell spray foam, but it is not accepted as a reliable air barrier. Any product or method suggestions will be greatly appreciated. Thanks.
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Jon,
For more information on using spray foam as an air barrier, see this article:"Air Leakage Through Spray Polyurethane Foam."
If closed-cell spray foam is installed at a thickness of 3/4 inch or more, it's an air barrier.
If for some reason you want to use a different product, a fluid-applied water-resistive barrier would work. For more information, see"Housewrap in a Can: Liquid-Applied WRBs."