How to Make a Cultured Stone Walk-in Shower

Cover the entire installation area of for your walk-in shower with a layer of paint-on waterproofing. Use a paintbrush to cover the inside corners and out the width of the brush, or around 3 to 4 inches. Cover the rest of the installation surface with a paint roller. Apply as many coats as the manufacturer recommends and allow it to dry at least 24 hours.

Mix thinset mortar according to the directions on the container. Do not add more water than called for on the container. Stir the mortar with a drill and paddle until you have a thick, creamy mixture.

Install the cultured stone on the floor first. Set the stones like tile. Spread a layer of thinset onto the floor with a 3/8-inch notched trowel. Set the stones in the mortar. Cover the entire floor and use plastic spacers to simulate grout joints. Wait 24 hours before you install the walls.

Stir a new batch of thinset. Spread it onto the bottom part of the wall. Press the stones into the mortar and set the entire bottom row before you install a row on top of it. Stack the next row on top of the first, using spacers between the rows. Work up the wall. Allow 24 hours before grouting.

Remove the spacers from the installation. Mix grout in a bucket and pour the grout into a grout bag. Grout the walls first, as the excess will fall on the floor. Insert the tip of the bag into a joint and squeeze the bag. Fill the joint and work up the wall. Grout only what you can clean up within 20 to 30 minutes at a time.

Wait 20 minutes after filling a joint to wipe it down with a dampened sponge. Clean off any excess grout with a tile sponge. Finish the walls and repeat the entire process for the floor of the shower. Give the installation 72 hours to dry.

Seal the installation. Use a spray-on sealer. Spray a heavy coat on everything and let it soak in. Test with water to see whether you have enough. Drop water onto the floor or splash it on the wall. If it pools up or runs down the wall, you have enough. Otherwise, apply another coat.