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Poly under slab on grade…

peaceonearth | Posted in General Questions on

I’ve understood that poly sheet plastic of at least 6 mil should go directly under a cement slab on grade.  At times I have read that the poly sheet can/should go below the rigid foam. I will be having pex imbedded in the cement slab, for radiant heating, if this makes a difference. Is there a preference on where the poly sheet goes?

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  1. GBA Editor
    Martin Holladay | | #1

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