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Opinions on this Basement Floor Assembly

thegiz | Posted in General Questions on

Just running this by as an option for basement floor.

1.2 coats moisture seal concrete floor (drylok floor sealer)
2. 6 mil vapor barrier (saw something called blue hawk)
3. Eva interlocking foam squares.

I will check underneath foam squares every few months since they are removable and clean or dispose of them if bottom is wet or has mildew. I’m hoping that 2 layers of vapor barrier will help prevent water from reaching bottom of foam squares.

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  1. GBA Editor
    Kiley Jacques | | #1

    Hi Joe,

    I’m giving your question a bump. Not too long ago, another reader inquired about EVA interlocking foam tiles. Check out what people had to say in this Q&A thread: Installing Foam on Concrete Slab.

  2. Jon_R | | #2

    I don't have perm values, but if the upward drying through layer 3 is greater than the wetting from below through layer 1, you should take Lstiburek's advice and skip layer 2. Less of a moisture trap and so less mold risk.

  3. thegiz | | #3

    Hi i was actually the one who asked this question before. What if I did this instead:

    1. 2 coats of moisture seal on concrete floor
    2 dry barrier floors, don’t know if anyone has talked about these they are completely made of inorganic material:
    3. Eva foam tiles on top

    The beauty of this is when I want to insulate and build walls all I have to do is lift up the Eva foams on the outside edges, build my walls, then put Eva foam tiles back against new walls. The moisture seal will help with floor, the dry barrier will create an 1/4 inch air space between floor and bottom of Eva tile. Plus the tiles will be a soft and insulated area for my kids to play. This is similar idea to putting down sleepers and raising the floor level for foam tiles without using wood.

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