Shower installations can be a difficult task for even the most experienced tile setters. All tile installation jobs require a strict attention to design, layout, placement, and bonding. With shower installations, though, you need to address some additional and unique challenges. Waterproofing, incorporating plumbing fixtures, achieving proper drainage and meeting code requirements. Changes in waterproofing, drain and tile-setting technologies will allow you to more easily meet these demands. Here are some things you need to know before tackling a tile shower installation:
1. Understand the installation requirements of the drain assembly waterproofing system.
Not so long ago, shower installers only really had one option for waterproofing showers: hot-mopping. That process involved installers applying a thick layer of hot tar to the floor of a shower pan, creating a waterproof seal that prevents leaks from damaging the subfloor. Hot-mopping is still done, however, today’s installer has a variety of other waterproofing options. These include roll-on, trowel-on, and sheet products. Installers typically place the waterproofing materials just below the surface of the tile, bonding the tile directly to the waterproofing membrane. This allows water to run off the surface and down to the drain before saturating the walls, avoiding any potential fouling spaces.
Regardless of what waterproofing system you decide to go with, you must completely familiarize yourself with all of its elements – to include the drain assembly. Failing to follow the specifications or the manufacturer’s directions can end up causing the need for expensive repairs. The entire system is critical: from the waterproofing product itself to the drain.
2. Test the waterproofing after it is installed, but before the tile is installed.
All too often Tile setters ignore testing. This is a final and critical step of the waterproofing process. Once the system is in place, but before installation of the tile, you must ensure waterproofing is completely effective. This confirms that you have a functioning system, which is absolutely essential to a long lasting installation. If a leak is found, it can be repaired before it causes any damage.
3. Be sure of the compatibility of the materials involved.
After the waterproofing system is in place, you can go back to the basic aspects of installing tile. Using the proper setting materials, ensuring 95% coverage and achieving straight and plumb lines. When you are choosing setting products, be sure that they will work with both the type of tile being used and the waterproofing system. For example, mastics are not acceptable for bonding tile to membranes. Normally, in a shower installation, you will need to use a modified bond mortar; though some uncoupling membrane manufacturers require the use of unmodified mortars. Whenever possible, try to use the same manufacturer’s materials for all steps of your installation. Having one point of contact for all installation materials simplifies things should any issues come up.
Linear drains have allowed for the use of large format tile in shower environments. Not so long ago, tile 6 inches or smaller could form the proper slope to the small drains. With linear drains, however, it is possible to place larger tile on the shower floors, giving both the owner and designer additional options.
4. Ensure sure you achieve 95% mortar coverage.
When working with large format tile, setters commonly make the mistake of using the “dot method” of installation. Using this method, the installer puts blobs, or dots, of mortar on the back of the tile, instead of carefully troweling it. The dot method might seem like a time-saver, but it will not provide a successful installation in the long run. It does not create full substrate contact or proper embedding and may cause voids behind the tile that collect moisture and potentially house bacteria. When using natural stone, there are even instances when the dots of mortar are visible through the tile. This can leave unsightly circular stains, efflorescence and color variation.
Remember that tile installations in wet areas, such as showers, requires 95% mortar coverage. When using natural stone, that requirement increases to 100%.
5. Using 100% silicone caulk can prevent mildew and cracking in the grout joints.
Improvements in grout and sealant have expanded the variety of products available to setters and their customers. For wet areas, many owners request grouts that are low in absorption, do not require any sealing, and are stain resistant. These types of grout are now available and recommended for such use. 100% silicone caulking has become the product of choice for the flexible sealant required in showers. These caulks prevent mildew and cracking in the grout.
6. Know the cure time requirements of the of the setting materials before putting the wet area into use.
Once installation is complete, be sure to abide by the cure time requirements of the setting materials before the shower is put to use. This can prevent potential problems or mishaps for the customer. It also shows the owner that you know and understand your craft and want to give them the best work, from beginning to end.
Advances in products and installation techniques have expanded the performance and aesthetic possibilities for tile and stone shower installations. In the tile industry, one trend remains constant: the perpetual introduction of new and exciting tile and stone goods along with the materials to set them.