How to Install Bathtub Molding

Molding goes around the perimeter of walls, separating the trim work from floors, ceilings and other surfaces. Wood typically comprises the makeup of molding, but around a bathtub, wood makes a poor choice because of its reaction to moisture. Molding can be pieced together with bullnose tiles, which are similar to regular tiles except that one edge is finished and rounded, so it can sit exposed along the wall. Lining up the bullnose tile on the wall, along the rim of the tub, creates the molding span.

  1. Run your sanding block along the wall around the perimeter of the tub. Get the wall clean and dull on the areas where you're going to place the tiles.

  2. Measure the length of the tub rim along one edge. Find and mark the middle of the span.

  3. Hold a bullnose tile in one hand. Spread tile mastic over the back of the tile, using your notched trowel. Cover the back completely.

  4. Press the tile onto the wall, above the tub rim, with the bullnose finished edge of the tile facing away from the tub. Set two spacers between the unfinished edge of the tile and the tub rim.

  5. Set the rest of the bullnose tiles along the length of the rim in the same manner, building out in both directions. Cut the tiles at the ends to fit, using your tile cutter. Repeat for each span of the edge of the tub. The finished edges of the tiles must form a line around the perimeter of the tub.

  6. Let the mastic set 12 hours. Remove the spacers.

  7. Spread grout onto the tiles with your grout float, scraping it across the tile face and pressing it into the spaces. Don't grout the space between the tiles and the tub rim. Use a damp sponge to wipe up the excess grout.

  8. Let the grout dry for 24 hours. Caulk the space between the tiles and the tub rim and allow 24 hours to dry.