QUESTIONRecently, there was a particular job where we applied waterproofing on top of existing tiles and new tiles were placed above. This didn't cause any issues initially but more and more tiles are now starting to make a squeaking sound every time someone steps on them. From the surface, there are no evident cracks in the tiles or the grouts and we are not sure what to check.
What do you think is the cause of this issue? Should we check the substrate or membrane?
Any opinions or advice would be greatly appreciated. Thank you.
ANSWERANSWER - Squeaky tile floors normally mean that either the wood sub-floor under the tiles is not stable in those spots or wasn't fastened down properly.
When you install tile over tile the new tile installation can only be as good as the original tile installed. So maybe it is the wood sub-floor below the wood tile that is the problem; if there is a wood sub-floor.
Sometimes we get tiles making a popping sound that is generally due to tiles that are not well bonded. Often the tile installation does not have any movement joints at the perimeter of the tile installation as well as within the filed of tile as the industry standard EJ171 requires. The lack of movement joints can put the tile under compression that can cause the tiles to loose their bond.
The only way to know for sure is to remove the squeaky tiles and look for evidence to indicate the cause of that sound.