Preparation

  • A shower with ceramic tile flooring–especially in a home with an older bathroom–is susceptible to water damage. The cement mortar that lies beneath tiled floor can become saturated with water and can eventually cause the grout to crumble, allowing in more water. Although a shower pan liner installed beneath this cement mortar prevents the water from damaging the sub-floor beneath the shower, over time, the shower pan liner will experience deterioration. If the floor near your shower becomes damp, it is probably time to install a new shower pan liner.

    Begin by cutting through a grout joint that is at least 3 to 6 inches above the dam height of the shower (the curb of the shower). Do this all around the entire inside of the shower. Remove the tile and the mortar below it so that you can see the sub-floor beneath the shower pan. If the sub-floor has deteriorated, you will need to repair it before installing the new shower liner.

    Installation

  • Correctly installed shower pan liner
    Correctly installed shower pan liner

    Put in the drain base. You will now need to apply a layer of mortar (one common dry mortar mix calls for one part cement to three parts sand) to the sub-floor that is approximately 2 inches thick and slopes to the drain base. Allow the mortar to cure.

    Put the new shower liner over the layer of mortar and nail it to the wall studs all the way around the shower, making certain that the liner comes up at least 6 inches from the base and that the shower curb is completely covered.

    Completion

  • Add a second layer of mortar over the top of the liner. Use wire mesh to reinforce this layer. This will also achieve the correct slope for the shower floor. Allow this layer to dry.

    Apply a layer of latex-modified Thinset mortar and set in the new tile. After this has had a chance to dry for 24 hours, use latex-modified grout to grout the joints.