Modified Flash and Batt in Dallas, TX (zone 3)
I’m considering what I would call a “modified” flash and batt using 1″ or 1.5″ of polyiso cut to fit between the studs on my house rather than spray foam, and then sealing the edges of the polyiso with canned spray foam. On top of that I would then add the unfaced fiberglass batts. The sheetrock is already down due to other renovation work taking place, and I’d like to cut down on the electric bill, particularly in the summer. everything I’ve read an research on DIY sprayfoam makes it sound pretty aweful to deal with, plus it’s about $1/ board ft (if their projections are accurate) vs ~ $.50 board ft for polyiso.
Anyone see any problems with this beyond it being a lot of work? (moisture is obviously the main worry)
Thanks for your comments and assistance.
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