How to Cut & Install
a New Tile Floor
WHAT YOU NEED FOR THE PROJECT:
- Tile and grout sealer
- Tile underlayment
- Grout release agent
Step 1: Prepare the Substrate
- Before you begin tiling, wash the floor with a commercial detergent such as TSP (tri-sodium phosphate) to remove dirt, soap film and other contaminants that could prevent adhesion
- If you tile on plywood, a double layer of plywood with overlapped seams is recommended. The bottom layer should be a minimum of 3/4-inch thick. Use screws to attach this layer to the floor structure
- Tile mastic, or thinset, is a premixed adhesive that is easy to use right out of the can, and it bonds well to almost any surface. It is commonly used directly on plywood or on cement board.
- Cement board is a highly stable, cement-based, sheet material typically reinforced with fiberglass. It is installed with special screws recommended by the manufacturer.
- The top layer can be 1/4-inch plywood, or a commercial substrate made specifically for flooring underlayment. This layer also must be adequately attached with screws, or according to the product directions.
Make sure to use the best substrate for your type of floor tile. If you are laying new tile over old, make sure the old tile is secure. Fill in any gaps in the old tile and sand before proceeding.
Step 2: Lay Out the Pattern
If the rows end with full tiles close to the walls, you may be able to avoid making any cuts by adjusting the spacing slightly. If the end tiles have to be cut to fit, do not use pieces that are too short — they may have a poor appearance or will not adequately bond to the subfloor, especially in doorways where there is more foot traffic. This often can be resolved by cutting the tiles at each end of the row by an equal amount. Adjust the tiles on your centerline so that you end with at least a half-tile at entryways and other high-traffic areas. Or, start with a full tile at the main entry and let the short tiles fall at an end wall where they will be less noticeable and not subject to foot traffic.
- Start by measuring the floor
- Snap a chalk line down the middle of the floor’s longest dimension
- Mark a second line across the middle of the floor’s shortest dimension
- By dividing the room into quadrants, you can begin tiling from the center point using your lines as a guide
- Before you apply mastic and install the tiles, do a dry run to check your layout and make any necessary adjustments
- Lay out enough tiles along your lines to reach the walls in each direction
- Use plastic spacers between the tiles. Your tile supplier can recommend the correct size spacers for your tiles
Before putting down the mastic, do a dry run of your layout and make any needed adjustments.
Step 3: Make the Cuts
- A wet saw (which may be rented) uses a water-cooled diamond blade to make perfectly smooth cuts in all types and sizes of tiles, including thick paving tiles, hard ceramic tiles, delicate glass or porcelain tiles, and natural stone tiles
- If you have calculated your layout correctly, you can often cut all of the required tiles for row ends and corners before you begin setting the tiles in the mastic
- Compound cuts and tiles that must be cut to fit while you're working can be measured and shaped as they are required
If you don't have access to a wet tile saw, a manual snap cutter works with small jobs and thin tiles. If using a snap cutter, make sure to smooth the jagged edges with a file.
Snap Cutter 1:
Snap Cutter 2:
Wet Tile Saw:
Step 4: Apply the Mastic
- Spread adhesive around floor with notched trowel
- Starting at your layout lines, bond the mastic well by pressing it against the floor
- Using trowel edges, create ridges the size of the notch depth by raking mastic
- At the end of this process, your layout lines must remain visible
- Work in a small, square area so the mastic doesn't dry out before placing the tiles
- Make sure no pilot lights / flames are within the vicinity of the mastic and provide proper ventilation due to fumes
For small tiles / mosaics, use a 1/4" notched trowel. For large tiles, use between 3/8" - 1/2" depending on size / thickness.
Step 5: Lay the Tiles
- Begin at intersection of layout lines
- Carefully place tiles into adhesive
- Work from center outwards to walls
- Gently tap tiles into mastic using hammer and wood block
- Avoid having masitc come up between grout lines by not pressing or shifting tiles around
- If tapping causes cracks in tile, remove pieces and spread a small bit of masitc on a fresh replacement tile before setting into place
- Put plastic spacers between each tile as you work
- Spacers are removed easily and the mastic will not stick to them
- Use level to make sure edges are aligned and tile is level throughout
Plan ahead to make sure you won't have to step on tiles already placed as you work.
Step 6: Grout the Joints
- Allow the tile mastic to set for at least a day before removing the spacers and grouting the joints
- Use a rubber float to squeeze the grout into the joints
- Ensure that the grout completely fills the spaces between the tiles
- As you work, clean excess grout off the tile faces with a coarse cloth or damp sponge, but be careful not to wet the grout, which will weaken it
- Wipe diagonally across the joints to avoid pulling the still-fresh grout out of the grooves
- After the grout has dried thoroughly, use a release agent to clean any grout haze from the face of the tiles
- Apply a grout sealer according to the product directions.
Mix the grout in batches that can be applied within a half-hour or so to prevent it from drying as you work.