LVP over basement slab
user-7751921
| Posted in General Questions on
We have a customer who would like LVP installed over their basement slab. The slab is not insulated. There are no moisture issues. We will be insulating the walls with InSoFast panels and hanging drywall.
In The Stay-dry, No mold Finished Basement by Gary Engle, he said to not install vinyl over the EPS & plywood subfloor because it would it would block moisture.
https://www.finehomebuilding.com/2005/03/01/the-no-mold-finished-basement
What is the recommended approach for installing LVP in a basement with an un-insulated slab? The location is central Indiana.
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Replies
Jeremy,
Do you have headroom to install rigid foam on the floor followed by to staggered layers of plywood or OSB?
In any case, this thread might be helpful: https://www.greenbuildingadvisor.com/question/rigid-foam-on-basement-floor-and-support-posts.
That article is from 2005. The idea that concrete will dry to the interior has been pretty much discredited since then. You want to have interior assemblies that don't allow vapor to pass and are impervious to moisture. LVP fits that description. What it lacks is insulating capacity. If you choose to insulate below it the insulation should also be impervious.
The problem you'll run into is that LVP need a firm substrate, otherwise it will flex at the joints and crack. Foam alone won't do it. Plywood isn't really appropriate as a subfloor because it's not impervious. There really isn't a perfect solution.