Rigid Foam on Attic Floor?
I’ve been reading a lot about upgrading the attic insulation in my single floor zone 5 home. My first stop has been air sealing my attic, which has so far proved to be fairly miserable work with the number of penetrations we have.
As I’ve been up there working, I’ve wondered to myself: is there any reason I can’t lay a level of polyiso foam across the joists on the attic floor, close off this toping at the top plate of the exterior wall, and then put unfaced batts across this topping for additional insulation?
Am I missing something or would this be a reasonable way to air seal and insulate all in one? Sorry if this has been written about, but I haven’t seen anything on this specific topic!
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