Approximately 75% of the cost of tile can be attributed to the installation IF IT IS DONE PROPERLY. Of course, there are many contractors who will gladly cut corners in order to reduce the price, but the homeowner pays in the long run.
Sub-floor Preparation
When installing tile, the condition of the sub-floor is critical. Tile has NO ability to flex or adjust for irregularities, so the sub-floor must be flat, firm and structurally sound.
Over Concrete - Typically, tile is installed over a concrete slab. With older concrete surfaces, uneven surfaces and stress cracks are common problems. A leveling compound can be applied by the installer on the job site to repair minor cracks or uneven surfaces. More significant cracks in the concrete must be repaired prior to installing ceramic tile. “Vertical” cracks, where the floor is at different levels, can not be fixed. In such case, carpet would be a better option.
Over Wood - On upper floors or main floors over a basement, the most common sub-floor is wood. Ceramic tile should NEVER be installed directly over wood. Hardwood moves with changes in temperature, causing the tile and grout to break. Consequently, whenever installing ceramic tile over a wood sub-floor, the installer should first install a cement backerboard and then install the tile over the cement backerboard. This ensures a level and clean surface on which to install the tile.
Buyer’s Tip: Watch out for installers who cut corners by using backerboard made of plywood or particleboard, which will break down if exposed to moisture.
Cutting the Tile - Straight cuts are made either with a power wet saw or by scoring and snapping the tile. Curved or finished cuts can be made with tile nippers (like a big pair of nail clippers), a tile saw (cutting and snapping small sections at a time), or a carbide rod saw.
Setting the Tile in Mortar - The mortar is mixed and spread on a section of the backer board or concrete sub-floor. This process is sometimes called “combing” due to the criss cross pattern used to increase adhesion. Tiles are then pushed into the mortar and leveled.
Buyer’s Tip: Some installers cut costs by using mortar that is rigid, causing the tile and grout to break with the natural movement of the sub-floor. Problems also arise if mortar is not spread evenly, leaving gaps under the tile (which can then break when walked on) or if the installer uses a trowel that is smaller than specified, resulting in less mortar over a larger area, which reduces tile adhesion.
Adding Grout - For applications in which there is 1/8" or less between tiles, "un-sanded” grout should be used. For plans that call for wider grout line, a sanded grout with a little more bulk will better bridge the larger gaps.
If there is less than 3/8" of space between the tiles (which is usually the case), grout is basically mixed and wiped on. The semi-liquid grout finds the lowest point and automatically fills in the spaces between the tiles. Once hardened, the excess grout can be cleaned from the tiles.
Sealing Tile & Grout – Tile made from natural stone MUST be sealed with a stain sealant. Ceramic and porcelain tile does NOT need to be sealed. However, ALL GROUT lines must be sealed.
Grout can only be sealed after it has cured, which can take up to seven (7) days. That’s why many customers seal the grout themselves. It can be done using a sponge and bucket and does not take a great deal of time.
Quarter Round Molding
Quarter round should be applied around the perimeter of the baseboard to finish off a tile installation. Quarter round molding is available in both paint and stain grade so that the customer can match the baseboard.
