Hi. I am new to the site, but was hoping for a little advice. I am retiling our master bathroom which was an addition to the existing house done by the previous owner. It is a greenhouse on slab, while the house is on pier and beam. The addition is a Four Season sun room on slab. My questions are as follows. This is really more of a wet room than a master shower. Measures 12 feet by 5 feet. I have suspected that the grout was old and that we were having some peripheral water damage to the tiles where the greenhouse structure met the tiled walls. That was pretty obvious but it was not a gapping hole - just a poor caulk job. When I removed the floor tiles in the shower pan, however, it was clear that the corners were very wet and the middle was pretty wet. It was wet enought that now two days later you can still see the darker cement in the corners and it smells like dirty socks. I have been taking this project very slow. The last time water was run in the shower was 4-5 weeks ago, but I just removed the shower floor two days ago. I am letting it dry out to see if the water comes back. I have caulked all outside around the base and anywhere the sun room touches an exterior wall. So, I guess I am trying to figure out whether or not a minor grout crack could result in a substantial glaze of water standing in a shower pan five week later or should I be concerned that there is something else going on? I have had foundation work done in the past to stabilize the slab of the sunroom but I don't believe there has been additional movement. I have good drainage away from the sunroom outside and a french drain for an extra measure. Don't believe there is a water line leak. There are some small cracks it the foundation, but they don't appear to be substantial. If it is being caused by the old crack (1/16th or smaller) I am surprised that 1) the drain weep holes did not take care of it and 2) that it could still be sittin around that long. Thanks so much.