Ceramic tile can create a beautiful, long-wearing floor that cleans up easily and needs next to no maintenance. The huge variety of patterns, color and sizes makes tile more versatile than many other flooring choices.
It can also be a bargain. Ceramic tile states at less than $2 a square foot, and the materials used to set tile are readily available at big-box stores, as well as tile and flooring retailers. What few specialty tools are needed can be rented. For all those reasons, tiling is something many homeowners try themselves.
For difficult installations — wet locations, oddly shaped rooms or very complex tile patterns — hire a professional tile setter. But when the pattern is simple and the room is fairly small, laying tile is not an overwhelming job. A small rectangular hallway or entry might be a good place to start.
We can’t cover every installation contingency for how to tile a floor here. If you’ve never set tile before, don’t hesitate to seek more detailed information. The Tile Council of of North America, for instance, maintains an excellent website (tileusa.com) and publishes a thorough handbook on setting tile. And just remember that setting tile is something like painting: Preparation is everything.
Step 1: Check the bounce. Tile and grout will crack if laid over a floor with too much bounce. If there’s too much give in the floor, it must be stiffened before the tile goes down. An old rule of thumb limits sag to no more than 1/360 of a floor’s span. So, in a room 10 feet wide (120 inches), the floor should deflect no more than 1/3 inch at mid span (120/360). Some stone tile, however, is less forgiving, and very wide tiles won’t tolerate flex as readily as smaller ones. Ask your retailer for a recommendation for the specific tile you plan to use.
Step 2: Check the underlayment. Some materials — particleboard, for instance, or multiple layers of resilient flooring — are not recommended for tile. Tile can be set over plywood, but many installers prefer concrete backer board. The backer board is put down over wood subflooring in a layer of pre-mixed mastic or thinset adhesive, a powder mixed with water or a special liquid. After screwing or nailing the backer board down, reinforce the joints with fiberglass mesh tape and more thinset adhesive. The finished surface should be level and flat. Check with a straightedge or level.
Step 3: Plan the pattern. Start by drawing a plan view of the floor, noting dimensions carefully, and checking whether the floor is square. You’ll need these dimensions to order the right amount of tile. Knowing whether the floor is out of square will help you decide how to set the tile. You will almost certainly have to cut some of the tile, so the trick is to plan the cuts so they will be as inconspicuous as possible — i.e., not at the focal point of the room.
Step 4: Establish layout lines. Draw two lines on the floor at a 90-degree angle to mark the starting point for setting the tile. Exactly where you start is not as important as making sure you won’t have a lot of narrow cuts along one edge of the room and that full tiles are placed where they are most visible. Now start laying out tiles in a dry run, just to make sure you won’t end up with awkward cuts. Some tiles are made with small bumps along the edge that automatically set the spacing between them. Or buy plastic spacers where you get the tile. One trick to avoiding very narrow tiles at the perimeter is to widen these grout lines slightly.
Step 5: Mix the adhesive. Pre-mixed mastic is easy to use, but most tile setters prefer thinset adhesive. Follow mixing instructions provided by the manufacturer, as well as recommendations on the type of notched trowel that should be used to spread it. A slow-speed paddle turning in a heavy-duty drill at between 300 and 400 revolutions per minute (rpm) is a convenient way to mix thinset.
Step 6: Spread the adhesive. Using a notched trowel, spread a layer of thinset over the floor, beginning where the two layout lines converge. Spread only as much thinset as you can cover in 15 or 20 minutes, and work out from the starting point. Wiggle the tiles slightly as you set them to make sure they are bedded firmly and completely in the adhesive.
Step 7: Make the cuts. Tile can be cut in one of several ways. A snap cutter scores and breaks tile along a straight line much like a sheet of glass. A wet saw is more versatile, and you may be able to rent one where you buy your tile. Curves can be made with certain types of wet saws or with an abrasive blade in a hacksaw frame. Tile nippers are useful for creating odd shapes. You can cut the tile as you go, although cutting them when you do your dry run-through is another option.
Step 8: Clean out the joints. Before the thinset hardens completely, remove the plastic spacers (if you used them) and clean out any blobs of adhesive between tiles.
Step 9: Add the grout. Follow the manufacturer’s instructions exactly when you mix the grout. Too much water will make a weak mix, for example, and grout should “slake,” or rest, before it is applied. Apply the grout to the floor with a rubber grout trowel, holding it at a 45-degree angle and working the mixture between tiles. Remove the excess.
Step 10: Clean up. Let the grout sit until it starts to firm up and you can see a haze on the surface of the tile. Dunk a tile sponge into a bucket of clean water, wring it out, and start to work over the surface. Take care not to get too much water into the grout lines. Rinse the sponge often, and keep the rinse water clean. Once the floor dries, and the grout is set firmly, remove any remaining haze with a clean cloth.
Scott Gibson has been renovating houses and writing about them for more than 20 years. He is co-author of Green from the Ground Up: A Builder’s Guide and Toward a Zero Energy Home.