Tile is very attractive when installed around a shower. Keeping your tile sealed against water leaks is an important part of the upkeep of your shower. Bad grout in between your tiles, or a bad caulk seal around the perimeter of your shower may cause leaks to pour down behind the shower unit, or into the subfloor. These hidden leaks can cause great damage before they are visible to the naked eye. Sealing will prevent the majority of leaks.
Place the end of a chisel between the tiles that have bad grout and hit the end of the chisel gently to break away the bad grout. Vacuum out the hole to remove the dust.
Mix together your grout compound with water, in a bucket, using a putty knife. The compound should be as thick as cake batter.
Place a large dollop of putty on the area needing grout.
Run your grout float over the area at a 30 degree angle to push the grout into the hole. Allow the grout to dry for 20 minutes.
Run your grout float over the area again, at a sharp angle, to remove the excess grout. Wipe away any stray grout from the tile using a wet sponge.
Apply a caulk remover compound to the caulk around the edge of the shower, where it meets the tile. Let the caulk sit for the recommended amount of time, or until the caulk is soft.
Scrape away the old caulk using a putty knife, making sure not to scratch the shower surface.
Tape off the area for the caulk by putting down masking tape along the joint line, 3/4 inch away.
Place the caulk tube into the caulking gun and cut off the end of the tube. Make the cut at a 45 degree angle. Push a nail into the tube end to open it. Press the trigger a few times to get the caulk flow going.
Run the end of the caulk tube along the line made by the masking tape. Run a wet finger into the caulk to push it into the hole and smooth it out. Let the caulk dry the recommended amount of time, then remove the masking tape.