# foam mats buckling on basement floor **URL:** \ **Category:** Factual Questions\ **Created:** [November 29, 2017, 9:07pm UTC](https://boards.straightdope.com/t/foam-mats-buckling-on-basement-floor/803098 "2017-11-29T21:07:53Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![shinnen](https://avatars.discourse-cdn.com/v4/letter/s/c77e96/32.png) [@shinnen](https://boards.straightdope.com/u/shinnen)\ **Post date:** [November 29, 2017, 9:07pm UTC](https://boards.straightdope.com/t/foam-mats-buckling-on-basement-floor/803098/1 "2017-11-29T21:07:53Z")
Hi, This may not be the place to ask this, but let’s give it a try. A few years ago, we put interlocking (jigsaw style) foam mats over the concrete on the basement floor. For a couple of years they were fine, but then they started to buckle in some places and not in others. (There didn’t seem to be any rhyme nor reason as to where.) Does any know why this is happening, and perhaps … what can be done to prevent it? Thanks, … john ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [November 29, 2017, 10:29pm UTC](https://boards.straightdope.com/t/foam-mats-buckling-on-basement-floor/803098/2 "2017-11-29T22:29:00Z")
Perhaps they are buckling because they are absorbing water from the humidity permeating through your floor pad, which might vary from place to place. To test this you could pull some of the buckling ones up and put aluminum foil under them, and then put them back down. If they stop buckling there, it’s strong evidence that’s your problem. If so you could put foil or some other water barrier under them all. We are talking tiny amounts of water here, more humidity than puddles; foil would be completely waterproof but some kinds of plastic wouldn’t be. I’d also expect them to buckle in high traffic areas if they keep getting squished under foot, which would force them to get bigger sideways. But you say there’s no rhyme nor reason, so I suppose that’s not it. ---
**Author:** ![shinnen](https://avatars.discourse-cdn.com/v4/letter/s/c77e96/32.png) [@shinnen](https://boards.straightdope.com/u/shinnen)\ **Post date:** [November 30, 2017, 4:31pm UTC](https://boards.straightdope.com/t/foam-mats-buckling-on-basement-floor/803098/3 "2017-11-30T16:31:19Z")
Hi Napier, Yes, I too was thinking that moisture may be the problem. I’ve scanned the net for confirmation, of that or some other reason, but no one is really mentioning this problem. I was hoping to get a good handle on what it is before I decide what to do, i.e. put down a moisture barrier and re-lay them or go with something else. Right now I have a couple of the deformed ones out and will let them ‘dry’, to see if they fit afterwards. I’m inclined to think that you’re right though, and may go ahead with a moisture barrier and re-lay them. Yes, high traffic is also a consideration; and I do shift the equipment (treadmill, weight bench, etc.) from time to time, which may also create problems. Thanks for your help. … john ---
**Author:** ![Gus\_Gusterson](https://avatars.discourse-cdn.com/v4/letter/g/85f322/32.png) [@Gus\_Gusterson](https://boards.straightdope.com/u/Gus_Gusterson)\ **Post date:** [November 30, 2017, 5:52pm UTC](https://boards.straightdope.com/t/foam-mats-buckling-on-basement-floor/803098/4 "2017-11-30T17:52:54Z")
I laid down a subfloor of Dricore panels before installing the foam mats in our basement. Dricore is 2’x2’ interlocking panels with an OSB layer over a rigid plastic vapor barrier. I got them at Home Depot. We haven’t had any issues with the mats moving or buckling. The panels also provide some insulating value which makes the floor a bit more comfortable temperature-wise. ---
**Author:** ![shinnen](https://avatars.discourse-cdn.com/v4/letter/s/c77e96/32.png) [@shinnen](https://boards.straightdope.com/u/shinnen)\ **Post date:** [November 30, 2017, 7:34pm UTC](https://boards.straightdope.com/t/foam-mats-buckling-on-basement-floor/803098/5 "2017-11-30T19:34:37Z")
Hi Gus, So, you have the interlocking foam mats? How long have they been installed? Ours didn’t start buckling for about 2 years. … john ---
**Author:** ![Gus\_Gusterson](https://avatars.discourse-cdn.com/v4/letter/g/85f322/32.png) [@Gus\_Gusterson](https://boards.straightdope.com/u/Gus_Gusterson)\ **Post date:** [December 1, 2017, 12:43pm UTC](https://boards.straightdope.com/t/foam-mats-buckling-on-basement-floor/803098/6 "2017-12-01T12:43:57Z")
> [@shinnen](#): > > So, you have the interlocking foam mats? How long have they been installed? Ours didn’t start buckling for about 2 years. Yes, we have the interlocking foam mats. I think ours are 7/8" thick and we’ve had them for 6 or 7 years. They are as flat as the day I put them down. ---
**Author:** ![shinnen](https://avatars.discourse-cdn.com/v4/letter/s/c77e96/32.png) [@shinnen](https://boards.straightdope.com/u/shinnen)\ **Post date:** [December 1, 2017, 2:35pm UTC](https://boards.straightdope.com/t/foam-mats-buckling-on-basement-floor/803098/7 "2017-12-01T14:35:27Z")
Thanks Gus, Well, I’m inclined then, to put a vapour barrier over the concrete and relay new mats. … john ---
**Author:** ![Chefguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chefguy/32/138_2.png) [@Chefguy](https://boards.straightdope.com/u/Chefguy)\ **Post date:** [December 1, 2017, 3:37pm UTC](https://boards.straightdope.com/t/foam-mats-buckling-on-basement-floor/803098/8 "2017-12-01T15:37:06Z")
I keep hearing the thread title to the tune of “Blackbird”. Please tell me I’m not crazy. ---
**Author:** ![Stepcarver](https://avatars.discourse-cdn.com/v4/letter/s/ee59a6/32.png) [@Stepcarver](https://boards.straightdope.com/u/Stepcarver)\ **Post date:** [December 2, 2017, 5:32am UTC](https://boards.straightdope.com/t/foam-mats-buckling-on-basement-floor/803098/9 "2017-12-02T05:32:46Z")
…Jack Frost nipping at your nose…