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Polyiso designed for roofing OK in crawlspace?

David Martin | Posted in Green Products and Materials on

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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  1. GBA Editor
    Martin Holladay | | #1

    Q. "What is the purpose of the black paper facing?"

    A. The facing protects the friable foam.

    Q. "Is it OK to use in spaces other than roof applications?"

    A. Yes.

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