When you are considering remodeling your bathroom, usually the first thing to go is that nasty shower, bathtub, or shower/bath combination. Many homeowners don't know whether to install a pre-fab shower stall or a tile shower. For those who want a combination of the two, it is also possible to tile the walls and put down a fiberglass pan. This gives you the beauty of the tiled walls and the easy installation of a prefab pan. The only problem with the combo approach is that you are stuck with a fiberglass shower pan that doesn't look so great.
Now you can get the best of both worlds. With the right type of shower pan, you can have an easy-to-install, virtually leakproof prefab pan and a tiled shower floor, because you can simply tile over the pan. For do-it-yourselfers, this is much easier and more foolproof than the traditional tilers' method of forming a shower base from scratch.
Acceptable Shower Pans
Normally, you can't tile over standard polymer or fiberglass shower pans because they flex too much and will eventually crack the tile grout and possibly even the tile itself. Shower pans that are designed to accept tile are heavier and sturdier than a normal pan so that they can withstand the weight of most users without cracking the grout or tile.
Tile-Redi, a leading manufacturer of tile-over pans offers a wide range of shower pans that are ready for tile, including curb and curbless models as well as special features, such as infinity drains, tile-over drains, and shower seats. In a typical installation, the shower pan is set into a bed of mortar to level it and secure it to the subfloor, and the tiles adhere to the base with an epoxy adhesive supplied by the pan manufacturer.
The standard installation of a Tile-Redi polyurethane shower pan starts with a framed-in shower alcove that is sized for the shower pan. If the subfloor is wood, it should receive a layer of cement board to protect the wood from the mortar bed under the pan.
If there is access to the drain connection below the shower, the subfloor simply needs a hole for the shower pan drain assembly to fit through, and the final drain hookup can be made after the shower is completed. If there is no access below, the drain must be stubbed out to the proper height below the subfloor surface, and the shower pan drain assembly must be glued to the stubout when the pan is installed.
Once the alcove is ready, the installer lays down a bed of thinset mortar and spreads it evenly over the subfloor. The shower pan is then set into the mortar and leveled, then it sits undisturbed for 24 hours. Next, the walls are covered with cement board so they rest on top of the shower pan and are sealed to the pan with silicone caulk or with a special flashing followed by caulk.
For the tile installation, it's best to dry-fit and pre-cut all of the base tiles before applying the tile adhesive, which has a 45-minute pot life. The adhesive is applied with a notched trowel, and the tiles are laid in the standard fashion. Then, the walls are tiled up from the base. After the adhesive cures on the shower base and wall, all of the tiles get grouted, as with standard tile installation.