The customer wondered why a floor that wasn’t very old was breaking up. The picture shows ceramic floor in a bathroom where the tiles were loose and the groutlines were broken in places. The toilet was wobbly and insecure on its floormount, and seemed unsafe to use.
As I removed the toilet and took up some of the tiles, I could see that a leak had developed under the toilet, and water was seeping under the tiles and lifting them. The problem was that the toilet was not plumbed in with the right fittings to attach to the copper piping below, so it leaked. The leaking was out of sight, as the water was seeping under the tiles. Also, the tile should have been laid on a cement board or other secure underlayment for a stronger floor. Probing deeper, I found a rotting joist beneath the floor under the toilet which was causing the bathroom floor to sag in that area, and making things worse.
The fix, in this case, was to pull out all the tiles, remove the boards they were mounted on, and reinforce the rotten joist below. I replaced some of the subfloor in the toilet area, installed a new cementboard base, then had a proper toilet mount plumbed in with the correct attachments. Then I installed a new ceramic floor. The toilet could then be replaced onto a solid floor with a leak-free plumbing installation. The customer was delighted.