We are having 20 by 20 tile laid on our concrete floor in the basement (new constructyion) It is done in the brick pattern. After it has been grouted I have noticed that there are many low or high areas where the corners meet against the middle of the tile in the next row. Is this normal? I am worrying that possibly not enough thinset was used under the tile. Thank you for your time,
Marjorie

That is a large tile and concrete floors are not as flat as you might think. This adds to the problem but your installer is the blame here. A good tile layer can get a flat floor using the correct amount of thinset and a level. You tamp the tiles down until they are all flat and flush with the tiles next to it, he skipped that step.

Hi ballengerb

That works if installing point to point, not when installing with 1/2 split.

Take a few of the left over tile and put them on a flat surface. Push down on corners. If tile rocks, they are warped.

U will find the warped one closer to bottom of box.

Chuck

If you have warped tiles all bets are off but when was the last time any of us had ceramic tiles warped right out of the box?

Next time u in home depot/lowes, take one of the 20'' tiles from bottom of pile and put on floor. I did. Had a teeter- totter.

It depends on quality of tile.

Chuck

OK I'll give it a try but the concrete floors at a home center are rarely flat either. I would trust a edge of a 16/24 square over the floor at my HD.

I have expensive porcelain tiles and many seem warped.

Just on a side note When the I buy flag stone at the brick yard its stored in the vertical position because it can warp.. Same goes for new slate roof tiles. All forms of tiles can warp. Big tile is the worst.

Also a few tiles seem to be slightly different in size.

Bonz1, you tied to an old post. You can start your own by clicking on ASK. What is your question and what brand tile did you buy and where?