I'm working on prepping an old converted attic for Luxury Vinyl Plank (LVP) flooring, and I'm a bit confused about what to do with my subfloor. Under the previous carpet and vinyl, I discovered a lot of glue-covered, damaged MDF boards. The subfloor planks have quite a few gaps—over a quarter inch in some areas—and there are also knot holes that lead to the space beneath the floor. Given this condition, should I fill the knot holes with foam and perhaps use something like self-leveling concrete, or would it be better to reinstall something like MDF over the subfloor and put self-leveler on top of that? I've seen a million videos, but they all deal with different types of subfloors, so I'm not sure what the best approach is!
3 Answers
I wouldn't stress too much about the gaps. Just focus on making the floor smooth, as that’s more crucial for a good LVP installation.
I had a similar situation and decided to lay down a new plywood subfloor to fix the imperfections and to ensure a level surface before installing the LVP. It made a big difference and worked perfectly. It’s definitely a safer route!
For LVP, you'll need a clean, stable surface to work with. Some manufacturers recommend a plastic sheet underneath; make sure to pull out any staples or nails to avoid noise once it's installed. Nothing's worse than stepping on a floor that crackles underneath!
Thank you! That’s what I was thinking but lacked experience.