How to Build a Shower Pan With a RedGard

Bind the shower head to prevent any water from dripping into the pan. Cover the head with a towel or a thick piece of cloth and secure it with a length of duct tape.

Scrub the shower basin with a sponge soaked in a mixture of one part bleach and three parts water. Use a scrub brush to remove stubborn soap stains or mildew. Wipe the surface with a clean sponge and leave it to dry.

Stir the RedGard mixture with a paint stirrer to achieve a smooth and creamy consistency and remove air bubbles. Pour a small amount into a paint tray.

Insert the tip of a paintbrush into the RedGard. Apply the membrane in smooth strokes over the edges, corners and other parts of the shower pan where it curves or meets the walls. Also apply the RedGard up the walls by 6 inches. Inspect the surface to ensure you haven’t missed any spots, and fill in with the membrane where required. Set the paintbrush aside.

Soak the nap of a 3/4-inch-thick roller in the RedGard and roll it over the floor of the shower pan to coat it with a thick, impenetrable layer of the waterproof membrane. If required, use a small paintbrush to reach parts of the shower pan inaccessible to the roller.

Allow the RedGard to dry for two to three hours, or until it turns into a solid red sheet. Avoid covering the shower pan with tile until the surface of the shower pan completely turns red and doesn't feature any pink spots.