Using XPS to raise floor height
PLIERS
| Posted in General Questions on
So I’m working on a small room that is connected to my kitchen. It is only 7×8. The floor from kitchen to small room drops about half inch. I want to install a floating floor that runs into this room from kitchen. Instead of installing a new subfloor can I simply lay down half inch of XPS foam in small room to even out floor height? Is there any specific way to do this? I was going to just glue it down while staggering joints.
Thanks for your help,
Joe
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Replies
I can't think of a good reason to do this, and a couple of big reasons not to. First, even though XPS feels quite rigid, directly under a floating floor it's definitely going to be a bit spongy. Second, the global warming impact of XPS is at least a thousand times higher than using 1/2" plywood or OSB. When it comes to green building, XPS is pretty much the worst.
You are right about XPS. Can I actually just glue down this plywood since it’s technically only an underlayment? I’m not over a bathroom but just nervous I might hit something screwing it down into floor, I can’t see what is underneath
What is the current substrate on the floor of this room? Most likely you can glue the plywood down with construction adhesive.
Right now it’s cheap stick tiles, I think vinyl or linoleum attached directly to a subfloor or underlayment
You’re probably ok gluing the plywood down, but I’d check to be sure the existing floor is solid first. This is similar to painting over a previously painted wall: if one of the existing paint layers starts to peel, your new paint is going to bubble up and come off too.
If you can determine how thick your existing flooring is, you can get screws just long enough to grab onto the existing floor without over penetration. You could use screws like that AND glue to help make sure your new floor stays solidly together over time.
Bill