Prevent mold under basement floor
smac355
| Posted in General Questions on
Hi All – we are about to finish our basement in Climate zone 4. When we built the house we installed 2″ rigid foam under the slab and ran that up the wall for a continuous thermal break. All foam has been taped and a additional vapor barrier was put on top of the foam before they poured the slab.
My flooring contractor stated they would put poly under the luxury vinyl floating floor. Is this necessary given the vapor barrier and under slab insulation? I don’t want to trap moisture and create mold problems given the luxury vinyl which already isn’t a breathable material.
THANKS!
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Replies
smac355,
The LVF is already a vapour-barrier, so you will not get any drying from under it whether you use poly or not.
I don't think the poly does any good or harm, but I would probably do along with it to keep the installer happy, and forestall any later suggestions that its absence caused any problems with the flooring that may occur down the road.