Bathroom sub floor damp

4 Replies

Hi All,

I just gutted a bathroom in my first duplex!  The floors were terrible, porcelain tile over cement board.  The cement board was the consistency of west sand, and after a layer of linoleum/tar paper, I got to the original hardwoods. The tub perimeter was quite damp at this level.. Do I need to remove that as well, or can I just let in dry and use self leveling cement on top? Plan is to use Schluter-Ditra as a strong barrier and basis for "normal" bath tile... Thoughts?

Thanks in advance


I would replace it all.  It's nice to have a clean slate to work from and it will give you a chance to examine the joists and address any issues with the framing. 

Do you know the source of the water damage? You need to make sure everything is corrected or you will be doing it again. We are having to replace the flooring in one of my parents' places because the drain in the shower wasn't sealed right and the water was leaking on the subfloor and sheeting under the linoleum.

I'm taking apart the wall with the plumbing in it today.  I should understand the source of the water better later.

Definitely need to tear it down and do it right.  Find your leak / moisture first and fix.  Then gut the floor and rebuild.  The schlueter ditra is only waterproofing and wouldnt provide any strength. That rot would flex even with a sub floor over it and your tile would pop in no time. 

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