vetteshack
New Member
Hello... a few years ago as a novice shower builder I remodeled a bathroom in our basement meticulously building a custom base with the appropriate multitiered drain assembly, rubber liner, and respective layers of poured concrete. I then installed a backer-board (recommended by an employee at Menard's) which was not true cement board but advertised as being excellent for tile showers and much lighter weight than traditional cement board. I had the tile professionally installed and it turned out great! After the grout was completely dry I applied two layers of tile/grout sealer. My son moved home about 18 months ago and since has been using that shower daily. Now I am turning my attention to remodeling the rest of the basement. In doing so I pulled off the sheetrock on the back side of that shower and was surprised to see that water had penetrated the backer board and left stains and some mold in the lower quarter of the shower. Ironically where my rubber membrane runs uo part of the wall at the bottom of the shower there is no mold behind it(?). At any rate, the mold cleaned up fine and the backer board has not lost any integrity (still very solid). My first reaction was that I needed to replace the entire shower. Now after cleaning up the mold and validating the integrity of the backer board I'm wondering if it is just my neglect in not routinely sealing the tile that caused this. There is no sign of mold at all inside the shower and all of the tile seems secure and looks as good as new. Do you think I'll be fine closing this wall back up and ensuring I routinely seal the inside of the shower? I thought about using some sort of sealer on the back as well since I have the wall opened up (like an oil-based water penetration paint of possibly even spray on pruning sealer). Does that make any sense at all or should this be left bare in hopes of getting some air circulation in there to keep it dried out? Sorry this got long but I wanted to explain the situation as best I can.