How to Lay Tile Flooring
Time Required: Over 1 day
The key successful tiling is to carefully follow a measured guide or set of layout lines. They show you where to start laying the tile and are arranged so the tile is evenly centered in the room.
Layout lines must be square, otherwise you will end up with odd-shaped tiles at the walls. The best way to ensure square lines is to make a floor plan by drawing the walls of the room as accurately as possible on a sheet of grid paper. Be sure to include doorways and floor obstructions such as cabinets and fixtures.
Tip: Make a floor plan for greatest accuracy and draw your plan as large as possible on the page. Mark the dimensions of your scale, for example, 1-inch gridline = 1 foot of floor space.
Safety: Make sure your subfloor can support the tile, mortar, grout and furniture when the project is completed. Read our guide to ensure your subfloor is prepared.
Tools & Materials
- Find the center point of the room by measuring the four walls for their midpoints. Next, snap two chalk lines, one from the midpoints of two opposite walls, and another from the midpoints of the other two walls. Where they intersect will be the room’s center point.
- Check that the chalk lines are square by marking points 3-feet on one chalk line and 4-feet on a perpendicular chalk line starting at the intersection. Measure the diagonal space between each of these two points. If the distance between the two is exactly 5 feet, the lines are square. If the lines are not square, the tiles will not be centered and the room might look unbalanced.
- If the room is not square — which is common — you will need to make adjustments to the position of one line, and then square the other line using the 3-4-5 procedure.
- Lay a single half row of tiles in both directions without mortar, starting at the center point and working outward.
- Insert spacers between the tiles. Stop when there is not enough room for a full tile. If the space at the end of either row is smaller than one-third of a tile, adjust your chalk lines so half tiles appear on both sides of the room. Since you started in the center, one-third of a tile on one end means you’d have two-thirds of a tile on the other end and your room will look off-center.
Tip: Pull tiles from different boxes and mix them. Don’t just use tiles in order from one box at a time. Sometimes, slight tonal differences can occur between different boxes of tile. By mixing the tiles as you go, you’ll spread and mix these differences throughout your floor and they won’t be noticeable. Also, be aware that some tiles have directional arrows on the back. You must keep these arrows pointing in the same direction as you lay out the tiles to ensure pattern alignment.
- Be sure to wear safety glasses and rubber gloves when mixing and applying mortar. Also consider wearing knee pads to evenly distribute your body weight and protect your knees.
- Read the mixing instructions on the back of the package to make sure the mortar is properly mixed.
- When tiling an area that will adjoin with a different kind of flooring, like carpet or hardwood, a threshold transition is needed. Check with one of our associates prior to your project to find out which type is right for your project and when it should be installed. Some go in before tiling begins and some are installed at the end of your project.
- Thin-set mortar is the bonding agent used to attach the tile to the backer board or concrete subfloor.
- Use a large bucket and a drill with a mixing paddle. Clean the mixing paddle promptly so the mortar does not harden on it. Some mortars are labeled as “non-modified” and require a latex polymer admixture that will improve the performance of the mortar and increase bond strength.
- Porcelain floor tile must always be installed using a polymer modified thin-set to achieve the appropriate bond between the tile and the substrate receiving the tile. This also applies to exterior installations.
- Mortars must be allowed to stand for five to 10 minutes after mixing and cannot be used immediately. This is known as “slake time” and allows the chemicals in the mortar to fully activate.
- For wood subfloors where a backer board was installed, be sure to moisten the backer board by misting with a spray bottle filled with water before spreading the thin-set. Spray the backer board as you work, otherwise the backer board will soak up water from the mortar, causing it to dry too rapidly. This will impact how well your tiles adhere to the subfloor.
- Take care not to mix too large a batch of thin-set. It has a limited working life, and if you’ve mixed too much it will start to harden before you’ve had a chance to use all of it. If this happens, you’ll need to discard it and mix more. Do not add water after the thin-set begins to harden. It weakens the cement and severely affects the bonding between the tile and the backer board.
- Trowels have both a smooth edge and a notched edge. The notches are called teeth. The type and size of tile you’re installing will determine the depth and width of the teeth your trowel should have. Check installation materials packaging for guidance.
- The size of the notch determines how much thin-set is left on the floor receiving the tile. Typically, the larger the tile, the larger the notch needed.
- Use your trowel to scoop out a generous amount of mortar from your mix bucket. Starting in one quadrant at the center point of the room where your chalk lines intersect, begin spreading the thin-set with the flat side of the trowel and press it into the backer board at roughly a 45-degree angle. This will ensure the mortar fully adheres to the backer board.
Tip: Plan your installation so that you have an exit without stepping on any tiles before the thin-set hardens, which takes approximately 24 hours. In other words, don’t tile yourself into a corner.
- To begin, do one test tile to ensure the consistency of your mortar is appropriate. Put the first test tile onto the thin-set bed. Lay the tile flat and then with mild pressure, slide the tile 1/4 inch back against the thin-set ridges, then slide it back into place. Pull the tile up and check the back of the tile. It should be completely covered with thin-set.
- If you have areas on the tile not covered with mortar, it means you did not mix the mortar properly, did not spread the mortar evenly, or waited too long to set your first tile and the mortar started to dry. It may also mean you didn’t evenly and firmly press the tile into the mortar. Correct as necessary and proceed.
- Once you’ve confirmed you have the right consistency in your mortar, re-lay your first tile, ensuring it lines up with the chalk lines at the center and that it is fully pressed back into the mortar.
- Place two spacers along the side where you will add a tile, one on each end. Spacers are used to easily and quickly ensure equal spacing between tiles. Always position your spacers so they stick up and out. A common mistake is to lay them on their side in the corners where four tiles meet. If you do this they become embedded in the mortar and can be hard to remove.
- Now, set your second tile by aligning the edges and corners, hinging it down and slightly twisting it back and forth.
- Comb the thin-set using the notched side of your trowel, holding it at a 45-degree angle to the floor and lightly pushing the trowel teeth to the floor. Make sure you comb the thin-set in one direction. Avoid circular or swirling patterns. The combed channels will flatten out and compress when the tile is placed, ensuring the proper amount of mortar is present beneath the tile.
- Use a small, thin trowel to remove a small amount around the edges of your tiles as you go.
- Do not allow the thin-set to skim over or start drying as you go. If it does, remove it and apply new thin-set.
- As you lay your tile, always check them for dirt or dust. Wipe them clean if needed. The dust can affect how effectively the tiles adhere to the mortar.
- If you’re new to tiling, you may only want to apply enough mortar for one or two tiles at time. When choosing where to place the next tiles, know that it really doesn’t matter as long as you keep two things in mind: 1) Follow your chalk lines to ensure your tiles are going down in a straight line, and 2) make sure you’re not tiling yourself into a corner.
- After installing three or four tiles, place a 2 x 4 on top and tap lightly with a rubber mallet. This will level the tiles and embed them firmly in the mortar. Then continue spreading mortar and setting additional tiles.
- Throughout the process, use a damp sponge to clean off any mortar that ends up on top of the tiles. Do not let it dry. Once dry, mortar on the finished floor is extremely hard to remove. Also, check your alignment by stepping back every so often and looking down the tile edges to be sure the lines are straight. This should be done often, before the mortar starts to dry and harden. If you find alignment issues while the mortar is still wet, you can straighten them before continuing.
- If you need to take a break, always scrape up any mortar overlapping into an area you are about to tile. If left to dry, it will affect how well those new tiles adhere when you return to work those areas.
- Finish laying full tiles in your first quadrant. You’ll then be left with the space between those tiles and the wall where cut tiles are required. Again, lay tiles so that you do not tile yourself into a corner, which would force you to walk on the newly installed tiles.
- Finish laying all full tiles in your other three quadrants and let the mortar harden. Different mortars have different curing times, but most require you to stay off the tile for 24 hours.
- Now, you’re ready to start cutting tiles. For this task, you have two options: a manual snap cutter or an electric wet saw.
- The manual cutter is generally used for smaller jobs. But for jobs that require cutting a large number of tiles, you will need to purchase or rent a wet saw. If you ever do a tiling project with natural stone, always use a wet saw with that type of tile to prevent it from breaking or chipping.
- You’ll also need a tile nipper. These are used to make specialty cuts around things like plumbing fixtures, pipes and round corners.
- To cut a curve, mark the cutting line, then cut away bits of tile with the tile nippers. Wear safety glasses when working with the nippers, and smooth the cut edge with an abrasive stone.
- To figure out where to cut a tile that will fit into the space left along the wall, place the tile that you’re going to cut directly on top of the next full tile near the wall.
- Place two tiles upright against the wall. This will leave an expansion gap between the tiles and the wall that will allow the floor to expand without causing cracks. It will also account for the space needed for the grout line.
- Place a fourth tile against those two tiles and on top of the tile to be cut.
- Trace along the edge of the fourth tile with a china marker to draw a line on the first tile. This is where you will make your cut. Once you cut the tile, it will fit perfectly in the space. To avoid confusion, lay out, mark and cut small groups of tile at a time. Then, leave those cut tiles in the space where they will be installed. Also, plan to install your cut tiles in small groups to avoid mixing too much mortar and risking it drying out before you can use it all. To be safe, measure twice before cutting.
- To use the manual snap cutter, align the cutting wheel with the cut line you made with your china marker. Raise the pressing bar, and push the cutting wheel away from you using moderate pressure. This will score the tile.
- Lift the cutting wheel, lower the pressing tee, and strike the handle to snap the tile.
- When using the wet saw, always wear safety glasses. Adjust the fence or guide so the cut mark lines up with the blade. Hold the tile with both hands and advance the tile into the blade, guided by the fence. Cut slowly to avoid chipping the tile. Change the tile saw blades when cuts are not clean. Be aware that wet saws splash water and tile residue during operation.
- Grout fills the spaces between the tiles. Use the grout coverage conversion charts on the back of the package to determine the amount of grout needed, and always wear rubber gloves and safety glasses.
- There are several types of grout available: PolyBlend, in both sanded and non-sanded; Fusion Pro, a single-component grout that never needs to be sealed; Simple pre-mixed, a no-mix alternative to traditional grout; and Epoxy. A Home Depot associate can help you determine which type is right for your project.
Tip: For joints 1/8 inch to ½ inch, use sanded grout. For joints up to 1/8 inch, use non-sanded grout.
- Before grouting, remove all of your tile spacers. Again, leaving the spacers in place and grouting over them will compromise the integrity of the grout. You’ll also want to protect baseboards, trim and neighboring floors with painter’s tape.
- We used a cement-based grout for this installation. To mix cement-based grout, use a drill and mortar paddle in a bucket. Almost all cement grouts have latex polymer in the powder mix; others require a latex polymer admixture. Follow your manufacturer’s instructions.
- Similar to thin-set, once the cement grout is mixed, let it stand for 10 minutes before applying, and avoid mixing too much grout at one time. Just mix enough for small sections until you become comfortable with the spreading process.
- Spread grout in sweeping arcs with the rubber grout float held at a shallow angle. Apply at a 45-degree angle to the spaces between tiles to prevent the float from pressing into the spaces and creating uneven grout surfaces. Press grout into the joints, filling them completely. Focus on small 4-by-4-foot sections.
- After the grout is spread, remove the excess with the grout float held at a 45-degree angle. Work diagonally across the joints to avoid dipping into the joints. The cement grout will set in about five to 15 minutes and have a putty-like consistency.
- As soon as you complete one section, take a damp sponge and make light passes across the tiles diagonally to clean off the excess grout. Wring the sponge until no water drips from it before cleaning. Excess water can affect the consistency of the grout. Use both edges of each side of the sponge. Be careful not to press the sponge into the gaps. The drier the grout is on the tile surface, the harder it is to remove. Do as many passes as needed. The tiles won’t be clean on the first pass so be patient.
- Rinse the sponge frequently in clean water and change the rinse water frequently. The cleaner the water, the more effectively it will remove the grout from the surface of your tiles.
- Remove any remaining haze by using an old T-shirt or cheesecloth. If you have trouble, try adding a grout haze remover solution. Try to remove all of the haze before it dries completely. Again, the drier it becomes, the harder it is to remove.
- Help to slowly cure the grout by misting it twice a day for three days. Do not walk over the surface for eight to 12 hours to avoid getting debris and dirt in the grout lines.
- Grout sealer provides unsurpassed, invisible protection for grout. Sealing your grout is critical to keeping grout lines clean and looking like new. Sealers help prevent stains and keep mildew and mold from growing into the grout.
- Choose a sealer with a built-in applicator or pick up a grout sealer application bottle. You can also use a grout additive such as StainBlocker that provides stain resistance during the curing process.
- Follow the manufacturer’s instructions on when to apply your sealer. In most cases, you’ll want to first allow the grout to cure for about three days.
- Expect your grout sealer to last an average of one to two years before needing to reapply it. To test, drop water on the grout. If it seems to soak in, it’s time to reseal.
- Wipe up any excess sealer within 10 minutes. If you’re using glazed tile, be extra careful to only seal the grout.
- To finish your project, remove the painter’s tape from any protected surfaces. Cover the ¼-inch expansion gap left along the walls. You can do this with either matching bullnose tile or wood quarter-round moulding.
- If you weren’t required to do so earlier in the process, add any desired thresholds between your tiled floor and neighboring floors. With that, your tile project is complete, and you have successfully learned how to install tile flooring.