Corner showers with prefabricated bases require tile to be installed on two walls. Below you will find the instructions for the tiling process for the prefabricated base of a corner shower unit.
Waterproof the Corner Shower
Once you have installed the base of the corner shower, you must make sure that the walls and the spaces around the joints of the bases are waterproofed so they will resist mold and mildew. Apply asphalt cement to the flange of the prefabricated base, which is the point where the base connects to the wall. Please take note that there's a high potential for water seepage at this spot so do make sure you have waterproofed it thoroughly before continuing on with this installation process.
Cut a piece of felt or polyurethane large enough to fit around the corner of the shower walls and carefully staple this to the wall in order to effectively waterproof the stall.
Prepare the Substrate
Cut pieces of backer board to fit the walls of your shower stall and attach them to your wall studs with screws. Leave a .25-inch gap between the prefabricated shower base and the backer board, which you will then fill in with caulk. Also apply caulk along the joint at the corner of your shower stall where the backer boards intersect.
Apply Normal Tiles to Your Corner Shower
Mix and apply tile adhesive in small batches and begin affixing tiles to the wall. Start at the prefabricated base of the shower stall. Use a level to ensure that your tiles are properly aligned as you move upward. Avoid placing tiles around fixtures at this point. If necessary, tape the tiles together to help them adhere to the wall properly. Be sure to wipe away any excess adhesive from between tile joints. Then wait for the tile adhesive to cure.
Apply Special Tiles to Your Corner Shower
After waiting overnight for the bulk of the main tiles to dry, you will be ready to install the half-tiles and rounded tiles that will often be necessary in corners and around faucets and handles. Carefully mark and cut the tiles to shape with a drill and wet saw. Once you have cut the tiles to the proper dimensions, affix them to the walls. You'll use the same technique described above.
Remember to leave a .25-inch gap around each fixture to be filled in with caulk so that the caulk can expand and contract with different temperature and humidity conditions.
Apply Grout to Your Corner Shower
Once all of the tiles have cured, apply grout between the tiles. Use a grout float to force the grout between the tiles. Remove excess grout from the tile surfaces.