FLOR Carpet Tiles Destroyed My Floor & Subfloor (Don’t Use Them Under These Conditions!!)

As I shared last Friday, the floor and subfloor in our home gym are destroyed. I’ve been noticing a hump going through the center of the floor in the room since last summer, about four months after I installed the FLOR carpet tiles in our home gym in February 2023.

I won’t rehash all of the details. You can read about it here. Long story short, I thought it was due to the drought last year causing our perimeter foundation to sink as the ground dried up, which in turn, was leaving the piers in the center of the floor to push the floor up. But even after the drought was over and the rains came, it didn’t get better. Then this year, as the warm and humid weather came with spring and summer, the hump in the floor started getting even worse.

When I finally took the carpet tiles up, I saw moisture underneath them, and the middle hump in the floor looked like this. I placed that board across the hump so you could really see just how bad it is.

Since I originally thought the problem was with the foundation, I kept the appointment with the foundation guy on Friday, even though I was fairly certain it wasn’t a foundation issue after finding all of the moisture under the carpet tiles.

And sure enough, I was right. He came, he did his inspection, and he rereported that our foundation was perfectly fine and needed no adjustments or repairs. He suspected, as I did, that the problem was the FLOR carpet tiles not allowing the floor to “breathe”, thus trapping condensation underneath as the cool air from inside the house met the hot, humid air under the house. After looking under the house, he did think that we might possibly have a plumbing leak in a pipe running under the home gym floor. He based this on his observation that the dirt under a joint in the PVC pipe looked darker than the rest of the dirt, and he thought that could be because of moisture due to a leak. But he wasn’t sure, so he suggested I call a plumber to check it out.

I was thankful to learn that our foundation was in good shape. After all, a faulty foundation can potentially cause issues like cracking drywall, or even actual structural issues. So at least that news was positive. And as he suggested, immediately after he left, I called the plumber to make an appointment. So yesterday (Monday), two guys came to do a pressure test on our plumbing and they found that we did, in fact, have a leak. So the skinniest guy suited up and crawled under our house, into our very cramped crawl space, to search out the leak.

Side note: If I were to build a brand new pier and beam house, I’d make certain that the crawl space was at least two feet high, if not more. I love having a pier and beam house, but at the same time, I feel so guilty every time someone has to crawl into our cramped crawl space. The other guy couldn’t fit. Most men can’t fit under our house. So if you’re building a new pier and beam house, keep that in mind! Anyway…

After about ten minutes of crawling around in our tiny crawl space, he found the leak. He showed me a video of it. There was a very tiny, very slow drip in a joint under the kitchen sink. And to be clear, the kitchen is several rooms away from the home gym.

After he repaired the tiny drip under the kitchen sink, they did another pressure test, and everything was fine. So that’s the only leak we had. And both of them said there’s no way that a tiny, slow drip under the kitchen sink could cause that kind of damage in a floor several rooms away. In fact, the guy who had to crawl under there said that our crawl space, even though it’s very cramped, is also very “clean”. That was his word. So it’s not wet and muddy under there.

So back to the home gym, there’s no other damage in the room. There are no window problems, no ceiling/roof problems, no leaks anywhere else. So that just leaves one culprit — the FLOR carpet tiles.

As several of you suggested in my post on Friday, the problem is that our house is old, it’s built on a pier and beam foundation, and the crawl space is vented to the outside. I know for a fact that the subfloor in this room (and in all parts of our house that still have the original hardwood flooring) is just 1″ lumber, like if I went and bought a bunch of 1″ x 10″ and 1″ x 8″ boards and used those as a subfloor. That’s exactly what they did back when this house is built. And it’s very that there is no vapor barrier under the subfloor or between the subfloor and the hardwood flooring, although the areas in which I’ve taken up the original hardwood flooring (i.e., the hallway) did have tar paper between the subfloor and hardwood flooring. I would imagine that would be considered a subpar vapor barrier by today’s standards, and I would also imagine that 75-year-old tar paper isn’t as effective today as it was the day it was put down brand new.

So while these aren’t standard building practices today, it was standard back then. And it all held up perfectly find for seventy-five years until I came along and put FLOR carpet tiles down on the floor in that room. And because we live in such a humid climate, and our crawl space is vented to the outdoors, and we keep our house very cool (due to Matt’s health), putting those rubber-backed, non-breathable carpet tiles down on that floor created the perfect environment for condensation to get trapped and have nowhere to go. So as the subfloor and flooring soaked up that moisture over the last 17 months, it started bowing and bending around the floor joists.

Sadly, there’s only one fix. The flooring and the subfloor will have to be replaced. There’s no fixing that floor. It’s too badly damaged to salvage. Since I removed the carpet tiles on Friday, the floor has dried out completely. There’s no longer any moisture at all trapped in the floor. Now that the floor can “breathe”, all of that moisture has evaporated. But it’s not like the subfloor or floor boards straightened out as they dried. They dried in that same exact shape they were when the floor was full of trapped moisture, and we still have a hill going down the middle of our floor.

I’m not going to lie. This makes me want to cry. I haven’t cried yet, and I’m really trying to keep a good attitude about it, but I have my moments where I come pretty close. It’s just so disappointing to spend so much time on a room, only to have such a catastrophic failure in just a little over a year after finishing the room. But I’ll put on my big girl pants and face the challenge. I may allow myself to have at least one little cry over it, though.

This isn’t something that I’m going to jump into right away. The good news is that there’s no danger of structural failure. Even when the floor was full of moisture, it was still structurally sound. There were no spongy areas where we were concerned we might fall through. And now that it has fully dried out, it seems as structurally sound as the floor in the rest of the house. But the hill is a serious tripping hazard, and I’ve stumbled over it several times already.

So for now, I’ll have a good cry over it, wipe my tears, and then focus on finishing my studio and studio bathroom. Those are still my priorities. After those are done, I’ll come up with a plan for replacing the subfloor and floor in the home gym. I’m not sure what part I’ll do myself, if any, so I’ll just have to assess that when I’m ready. I may do all of it myself (with help, of course), or I may just do the demo of the current floor and let the pros put in the new subfloor and flooring. Or I may just let them do all of it. We’ll see. This is a disappointment, for sure. But I won’t let it derail me completely.

So that’s the story of our home gym floor, and my experience with FLOR carpet tiles. Our little home gym looked great for about four months before things started going bad. I just wish I had realized what was causing it last summer. Perhaps I could have taken the tiles up in time. Goodbye, my pretty little home gym. It’ll probably be quite a while before you look pretty again.

FYI, when I started researching if my FLOR carpet tiles could possibly be the cause of my floor issues, I came across this video. While it’s a different situation, it confirmed that the tiles were the problem, especially after foundation and plumbing issues were timed out. So I want to pass this along to any of you considering vinyl flooring. https://www.facebook.com/share/r/aT7QSVzViytNnag9/?mibextid=W40cHY

Addicted 2 Decorating is where I share my DIY and decorating journey as I remodel and decorate the 1948 fixer upper that my husband, Matt, and I bought in 2013. Matt has M.S. and is unable to do physical work, so I do the majority of the work on the house by myself. You can learn more about me here.