In a shower with traditional waterproofing on the walls (6 mil plastic behind 1/2″ durock), I was planning to tile the walls with thinset for 12×12 tiles. Is this the right approach? I’ve tiled walls (not for a shower) with the glue before, but just wanted to double check that thinset was the right option for the shower.

Thanks,
Mike

Run the kerdi up to the hole then as you are installing tile run a bead of silicone around the perimeter of the hole. As you install your tile it will sandwich the silicone between the tile and kerdi. Water running down the wall will run around that bead of silicone rather than into the hole. The trim gasket will prevent water from getting into it from the face of the tile.

This is a great website with tons of useful information. We are going to be tiling our shower and using Kerdi for the walls and floor for waterproofing. We just had a new shower mixing valve installed and have not yet put the drywall up on the plumbing wall. I am not sure what to do for sealing the mixing valve because the Kerdi mixing valve seal is for a 4 1/2″ opening and our Kohler mixing valve requires a 5 9/16″ hole in the wall. I searched online and was unable to find a Kerdi valve seal in a larger size. What is the best way to waterproof in this situation? Should I just run the Kerdi up to the edge of the hole and rely on the valve trim gasket for waterproofing? It seems like I need to have some sort of waterproofing seal behind the tile that will seal the hole and prevent water from getting to the drywall. Any suggestions you have would be much appreciated.

Thanks,

Greg