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Vapor barrier north jersey

Manny_Lourenco | Posted in General Questions on

Good day all. I have a question that I can’t seam to get a straight answer to. I am located in central NJ zone 4. Basement is partially under ground, bottom 3’.
I am preparing a basement slab in an existing construction for radiant heat. It has 3” of stone, 2” of xps foam board and a 15mil poly on top of the foam. My question is where would I terminate the poly, 6” above finished slab or at the edge of footing and block wall under the slab. I was told it doesn’t make a difference and I was also told that it is best to leave it above to collect any water that might make it in to the house. Eventually the basement walls will be spray foamed with close cell. Please help. Thanks Manny

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  1. Jon_R | | #1

    I'd bring the poly up such that any water that comes through the wall is directed below the slab (vs out into the floor).

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