Polyiso designed for roofing OK in crawlspace?
I want to seal and insulate my crawlspace walls and rim joist area in an affordable manner, which for me is about as close to zero as possible. So I found a guy who has a bunch of used 4’x8’x1.5″, with black paper facing on both sides, for $5 per sheet. In looks like its pretty good shape from the photos I’ve seen and the price seems like 1/5 the retail price.
My question is: what is the purpose of the black paper facing and is it OK to use in spaces other than roof applications?
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