Shower pan liner – The shower pan liners is a one-piece, waterproof liner in the bottom of your shower during installation. The sleeves prevent water damage from leaks that may be associated with poorly installed tile floors and cracked fiberglass shower surrounds. Lay shower liner over the bottom of the shower to find the center of drain hole in the floor. Cut a hole the size of drain lines in the middle of the liner. Remove the liner.
Apply a thin layer, 1/4-inch per foot slope, of Portland cement, starting from the edges of the shower base and inclined towards the discharge pipe. Make sure you do not cover the drain pipe with mortar. Allow the grout to cure according to manufacturer’s instructions. Lay pan liner over the bottom of the shower pan liner centering hole with drain pipe. Insert the drain flange over the top of the liner and sandwich liner between the flange and the top of the drainpipe. Using polyvinyl chloride solvent adhesives for bonding two pieces together.
Put a bead of silicone adhesive around the threads of the drain flange and install drain top of threading it into the flange. This will form a watertight seal around the edges of the drain, so water will just flow down the drain. Smooth pan liner out from the center, using your hands. There should be no wrinkles or bumps in the shower pan liner, which may cause the tile to give an uneven and water to flow in the wrong direction. When you get to the corners of the liner cut an overlapping V-groove with a knife, so the liner will sit square in the corner. You may need to apply a small glue lines to make sure it remains in place.