We have a tile shower stall that was built several years ago. The pan is composed of a membrane liner and concrete pad, with tile over that. The caulking around the perimeter of the floor would get moldy every 6 months or so, and I have to replace it. I think there is moisture behind the caulk that was causing the mold growth. When I remove the caulk, it was soft and wet. There is no leak that I can see. I’ve had a fan blowing in the shower for a week on/off, and there was still moisture in the gaps. I don’t want to fill the gaps again w/o knowing if there is a bigger moisture problem, and how to correct it. If you look at the pictures, the gap between the wall/floor varies from almost none to 3/16” Should I use grout to fill the void, or caulk? Any suggestions appreciated! Images are here -
http://imgur.com/a/fLo1V
http://imgur.com/a/fLo1V