HI, I have a shower that has travertine tiles. I noticed a crack at the bottm and went to our local tile store to find out what to do. The told me that the bottom joint shoul have had caulk instead of grout and to remove it back about an 1/8 th of an inch and caulk it. I have a fein multimaster so I started to remove it and as I got into it I noticed that moisture was coming out and making the dust into mud----ARG!! I have a heater in there trying to dry it out and I am worried that this could be major deal. I went into the crawl space and I can see where there are water stains but they could be old as it did not feel wet and has always been a shower location. The house is about 45-55 years old but the shower is new last 4-5 years prior to our purchess. Is the water trapped between the pan and the tile and will it be okay if I try to dry out and caulk and seal? Any advise would be much appreciated. Thanks in advance.

Too many times people forget that grout in not a true sealer. And when to re-seal the grout especially in tub and showers. Grout being wet to many times will breakdown/soften the grout. Even in Puerto Rico the walls floors and ceilings are all concrete;cement block we still use sealer on the grout in bathrooms and kitchens. Check the other grout lines before you seal the whole shower. Do it by lightly scraping it and see it its soft. If not get a grout cleaner and clean it dry all of the joints out and seal it. The water trapped does concerns me for wood rot or mold behind the shower/pan. I just hate caulk in bathrooms that yellow and get dirty but since you saw a actual crack showing movement caulk sadly is the way to go. Hopefully they used a cement backer board for the walls into the "pan" if so the upper section of studs should be all right. Try to dry as much as you can to prevent problems later.
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