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Community and Q&A

Basement bathroom & floor transitions

Matt Draper | Posted in General Questions on

Greetings. I want to finish my basement using techniques outlined in FHB “The Stay-Dry No-Mold Finished Basement”. My basement has a full bath (drainage through slab). Is it OK to use foam & plywood floor, as called out in the article, under a toilet? If not, I guess I would use tile. But then I’d have a transition problem from the rest of the basement (1 inch foam + 2x 1/2 inch plywood = 2 inch floor, compared to tile in bathroom). Thoughts?


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  1. GBA Editor
    Martin Holladay | | #1

    I see no reason why you can't install a toilet on the plywood subfloor. People do that all the time. The closet flange would need to be fastened to the slab with TapCons or similar fasteners, but that shouldn't be too hard.

    If you decide that you prefer a tile floor without any plywood or foam, you can make a transition at the door by installing a beveled threshold. That's not ideal, though -- it would be a tripping hazard.

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