Foil faced ISO over 3" closed-cell spray foam?
Looking for an answer before I start this project. I live in northern MN. I had my attic spray foamed 4" behind knee walls, 3" in the living space. This is a 1 1/2 story with a non-vented roof. I want to know if its O.K. to use foil faced 1" rigid sheets to cover studs [Editor's note: I think David means "rafters"], with the foil facing down between the knee walls. I did plan on filling all voids and foil taping the joints. Then 1/2" sheetrock over the foam. Just want to make sure this isn't considered a double vapor barrier, and if this would be considered good construction.
Posted Jul 27, 2014 2:16 PM ET
Edited Jul 31, 2014 4:36 AM ET
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