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Concrete Backer Board
The first step in building your tile shower floor is to prepare the work area. Make sure that there is a slight decline towards the drain. Remove all dust and debris, and make sure to seal the seams or cracks at the wall bases with waterproof caulk. If you are building your shower base on a concrete surface you can skip the rest of this step. Otherwise, cover the floor in concrete backer, or a silicate equivalent. Cut out a hole just large enough for your drain and place it snugly on the floor. Screw the board into place so that it is tightly attached to the floor. - 2
Tile Snips
The next step is to prepare your tile. It is good to have all of your measurements and cuts completed before applying mortar as it will dry quickly and produce a weaker bond for tiles laid later. Lay the tile that you intend to use onto the floor surface. Space them slightly apart to make room for grout. Use a pencil or erasable marker to mark any cuts (around the drain or at the wall edge). For a better appearance, start placing the tiles at the back corner of the shower closest to the wall with the faucet. This way any partial tiles will be hidden from view unless you are in the shower. Cut each tile using tile snips for angled, or partial cuts, and a tile splitter for straight cuts. Make sure that your cut tile fit your enclosure and then remove all of the tile. - 3
Masons Trowel
The next step will be to prepare your mortar. If you buy a powdered mix follow the mixing instructions on the package. You will want your mortar to be so thick that it will not drip off of your trowel, and free of bubbles. When mixed, start with the corner you placed your first tile when measuring. Use your trowel to apply mortar to the concrete board. For smaller tile (less than 10'') start with a grapefruit sized lump of mortar. Use the trowel to spread it up to the edge of the wall, and spread it about .25'' thick over the rest of the corner until you run out. Use the edge of the trowel to create indentations in the mortar. Place your tile one at a time, making sure to press them down very hard to push out air bubbles and get a better contact. Remember to leave space for the grout and then repeat this until all tile have been placed on the floor. Use a damp towel to wipe up any excess mortar. Its much harder to clean up after it dries. Allow to dry for 12-24 hours depending upon the mortar used. - 4
Waterproof tile grout
When the mortar has dried it is time to place the grout. Grout can be mixed at home or bought premixed. For a more professional appearance it is often better to buy it premixed. For easy application, many hardware stores will sell a grout applicator that closely resembles a cake decorating icing bag. Fill the bag with grout and push it to the front of the bag. Place the nozzle or nose of the bag against the edge of the tile right above a seam. Squeeze evenly and move the bag slowly along the tile seam as you do so. Using a soft trowel put the corner into the seam that has just been filled with grout. Using light pressure slowly drag the trowel through the seam removing excess grout and removing air bubbles from the grout that stays. For a nice even finish you can gently run the pad of your pointer finger through the seam and creat a nice even grout line. Continue this process for every seam and crack along the shower basin. Be extra careful around the preimeter of the shower and around the drain. Make sure to use a damp towel to remove grout from the surface of the tile before it dries. - 5
Grout Sealer
Allow the grout to dry for around 24 hours (check packaging as this may change depending upon the type of grout and the thickness of application. Using a liquid or a spray grout sealer, cover every inch of grout in the shower basin. The easiest way to do this is with a spray grout sealer. Stand a few feet away from the shower basin, point the can about 2 feet from the grout and as you spray, slowly move the can along the path of the grout. Wipe up excess sealant and allow to dry for 6-12 hours. Repeat this step at least once, twice for a large shower. For a test, use a small glass and pour some water into the shower. If the grout changes color (looks damp) in any area, then it should be allowed to dry and then be resealed.
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