Technical > Home Improvement > Pop from tile floor

Pop from tile floor

Do you also feel the floor move or is it just a sound? Have you gotten down with a straight edge to check for a dip?
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"While you can teach an old dog new tricks, you simply can't teach him to be a cat."

reply to jjoshua
Sounds as if the cement board was under stress and has broken.

reply to Sweet Witch

That part of the floor needs to be torn out. The crunching you hear indicates movement and that part of the floor will slowly disintegrate. Every time it moves a little more will break.

Question -- did they "bond" the cement board to the subfloor with adhesive or did they just nail it?

First problem I see -- as far as I know 5/8" subfloor is the minimum suitable subfloor for installation of cement backerboards. Personally I wouldn't use anything less than 3/4". I also don't like using mastic to bond cement board but if they used the proper mastic it probably meets spec.

The 3/8" subfloor could be causing problems as it is too thin and flexible. Cement board provides a good bond surface but in itself adds no strength. There is going to be movement inherent in this installation due to the thin subfloor.

Correct -- it should have been 3/4" over the diagonal subfloor. Basically tile installation specs don't allow for 3/8" as a subfloor material no matter what it is over.

reply to jjoshua
The show Holmes on Homes covers this particular problem alot. In a recent episode, he said your sub floor should be a minimum of 5/8" thick and screwed downed (not nailed) to the joists. Also, he said to use construction grade plywood with the rough side up. My guess, is that the subfloor was too thin, shifted, cracking the cement board (as stated before).

I really get a lot of great info from HoH.

reply to jjoshua
We had the exact same thing happen in our kitchen our house is 6 years old and out tile was put directly on the concrete. We have a post tension foundation and not cracks anywhere. What could this be?

reply to bryank
We watched that same episode too, I love Holmes on Homes we always learn something new. And I just love to hear him say "tear it all down"

In our previous house the tile that had been down when we bought the house had an area that the grout had cracked and it looked like it had been taken out and replaced yet it did the same again, when we ripped all the tile out we found that area was right over the top of one of the central heat and air ducts, so apparently the slab above it was being affected by the temps in the duct, the slab also had a little crack in it there too.

reply to jjoshua
Maybe the thin set wasnt put on thick enough and is crushing under the weight when you step on it? When you tap on the tile with your knuckle does it sound hollow? Just a thought. I think we use a 1/4" inch trowel when we lay tile and i usually keep the thin set pretty thick. Also you said your cement board was nailed down? They have special coated screws that we use on our floors and we use liquid nail/sub floor glue as well.

reply to jjoshua
Look for the simplest things first. Take solid (not metal), a screwdriver handle works well, and tap the tile surfaces in various locations around the suspected tiles and compare the sound to known good locations. You will recognize the difference between loose and tight tiles. The most likely problem would be a tile may have been moved slightly by the installer after it had been set too long. Or it may be that traffic was allowed too soon, and sometimes the thin-set just didn't cure as fast in some areas. This is a common issue and the tile setter would usually return to fix these type of issues without complaint.
In the meantime try not to imagine the worst until you have reason.
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My grandkids REALLY ARE cuter than yours!

reply to jjoshua

said by jjoshua
we also had a crack (grout and tile) all the way across where the kitchen meets the slab at the front door

said by jjoshua
The floor doesn't move any more or less in the one area. I don't see a dip in the floor.

reply to PeeWee

Re: Pop from tile floor

reply to robbin

I take it that you are a Tilesetter. Please provide reference and proper specifications allowing this practice. Specifically where does ANSI (American National Standards Institute), TCNA (Tile Council North America), or any other standards institute allow this practice and under what conditions and installation methods?