Is it OK to sandwich exterior wall sheathing between external foam board and interior flash coat closed cell spray foam?
I am building a new energy efficient home. The builder wants to have the exterior wall pre-fabricated and for structural stability wants to have the 2 x 6 walls sheathed with 1/2" OSB. The exterior wall would then get 1' XPS or polyiso, a Tyvek rain wrap, and then cement board vertical siding.
The interior will receive a 2" flash coat of closed-cell spray foam and the cavity finished with batt insulation.
I don't see a path for moisture to get to the OSB or plywood, but was interested in opinions on this procedure. Thanks for you input
Posted Apr 18, 2012 2:49 PM ET
Edited Apr 23, 2012 9:40 AM ET
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