nancyramirez•21h agoProlific Poster

Had to rip out 400 sq ft of vinyl plank last week because of moisture.

My crew and I installed this LVP in a basement in Denver about 2 months ago, looked perfect. Last week the homeowner called saying the edges were curling and it smelled musty. Turns out we skipped the moisture test on the concrete slab because we were in a rush, and the subfloor had a reading of 8% moisture. Had to tear it all out, let the slab dry for a week, and reinstall with a proper vapor barrier. Has anyone else dealt with moisture issues on a slab that seemed dry at first?

3 comments

3 Comments

ruby_bell4720h ago

Man, did you check for any hydrostatic pressure issues too? I had a similar job in a Denver basement where we skipped the test on a slab that felt bone dry. We ended up pulling up the flooring twice before we realized the concrete was wicking moisture up from a high water table. What finally worked for me was using a self-leveling underlayment with a built-in vapor retarder, plus I always tape the seams on the vapor barrier now, even if it's just a 6 mil poly sheet. That extra step has saved my butt on at least three remodel since then. A moisture meter reading at 8% sounds low but it's enough to warp vinyl if the slab is still sweating underneath.

hannahj4920h ago

@ruby_bell47 makes a good point about taping the vapor barrier seams. I actually read a study from one of the flooring institutes that said moisture problems in basements often show up months later because the slab takes time to equalize with the air. That 8% reading might seem low, but if the concrete has a high pH from the curing process, it can still break down the vinyl over time. We started using a calcium chloride test on every basement slab now, even if it feels dry, because those meters can be misleading. That musty smell is usually the first sign of a slow moisture issue building up underneath.

the_cameron19h agoMost Upvoted

Yeah it's wild how much this stuff applies to all kinds of home projects, not just floors. @ruby_bell47 I think the same principle holds for drywall or paint too - you can fix a leak or check humidity meters and still end up with hidden mold months later because the materials just take forever to dry out from the inside.