QUESTIONI had my kitchen remodeled with the floor tiled first on a wooden subfloor and cabinets installed the following day. This was in 2011.The grout has come off in different places and I can hear a crunchy noise when I step on a tile at one location. At another location I can hear a popping sound. What is causing this problem and how should I get it fixed. Two years ago, the grout came off at another location in the kitchen and two tiles were replaced by the same contractor. This problem seems to be continuing.
ANSWERANSWER - I am assuming that the ceramic tile was bonded directly to the wood subfloor. There are acceptable methods for installing ceramic tile over wood substrates in interior dry applications. It is always considered better to install over a mortar bed or over one of the approved tile backer boards.
To install over a wood substrate the floor needs to be structurally sound and not have any deflection greater than L/360. That configuration can be done with joists placed 24" on center although 16" on center is better. The subfloor must be a plywood exterior-glue tongue and grooved with a minimum thickness of 23/32" and with 1/8" gap between sheets. Then on top of that you have to install a plywood underlayment with a minimum thickness of 19/32" and with 1/8" gap between sheets. Then you can bond the tile to the plywood underlayment with an ANSI A118.11 motified thin-set mortar adhesive.
I suspect that if your floor is making noises when you walk over it that the wood substrates were not properly fastened. The noises could be an indication that you have too much deflection in the floor and that the tile bond coat is not bonded as well as it should be.
The grout coming out is an indication that the floor is not structurally stable enough and has excessive deflection. Chances are the substrate configuration and installation wasn't done correctly.
The only way to verify what the problems are and to determine how to fix them is to remove various tiles with various conditions to determine what materials were used and how they were installed.