Most do-it-yourselfers have no problem laying a tile floor if they use careful preparation and attention to detail. It can be done in six steps of progression:
Step One: Preparing the Substrate
Tile can be applied to a variety of surfaces to include existing tile, mortar base, cement board or plywood. If you lay over existing tile ensure that all the tiles are sound and all the mortar joints are properly filled. Scratching the original surface is also needed to ensure a proper bond of the new material. Tiling over thinset or mortar is the preferred method of professionals. These floors will be extremely durable. Tile mastic or thinset is also available in ready to use forms. It is commonly applied directly to plywood. When using plywood a minimum of ¾ inches is recommended. Cement board is very stable and requires special screws that are supplied by the manufacturer.
Step Two: Pattern Layout
To lie your patterns select the portion of the floor with the longest dimension. Measure to the center of that area and snap a chalk line to determine where to begin your pattern. Select the floors shortest dimension to snap a cross line to divide the floor into quadrants. When you begin laying the tile start at the center and use your lines as your guide.
Do a dry run before actually installing the tiles to ensure proper alignment. This will also expose the need for any adjustments. This is accomplished by laying enough tiles on your line to reach all the walls in each direction. Plastic spacers between the tiles will ensure proper and consistent alignment of all the tiles. Ideally you want the the tiles at either end to be close to the same size. Too small of a tile will not bond properly. In high traffic areas be sure to always use at least a half tile when possible.
Step Three: Cutting the Tile
Tiles are cut with manual snap cutters or with power saws. Snap cutters are used for small jobs and thin tile. They leave a jagged edge after scoring and snapping and a file or stone is needed to smooth the finished edges which show. A power saw or wet saw uses a diamond chip blade with water running over it while the tile is being cut. These make smooth cuts on all styles of tile whether thick or thin. With a proper layout design it is possible to cut all of your finish tiles prior to setting them into the mastic. Tiles that have compound cuts or special applications should be cut individually as they are required.
Step Four: Applying the Mastic
Using a notched trowel spread the adhesive on the floor. Trowels with smaller notches are used for tiles that are smaller. The larger tiles require the larger notched trowels. Start at your layout lines and work towards the edges. Press the mastic onto the floor and use the edge of the trowel to make ridges into it. Make sure to leave your lines visible. Confine your work area to three or four feet at a time. Be sure to have adequate ventilation. Mastic can have noxious fumes to it.
Step Five: Laying of the Tiles
Carefully press the tiles into the mastic beginning at the layout lines. Proceed so you won’t have to step onto the freshly laid tile as you are going. This is where a helper comes in handy. They can supply you with a constant feed of tile while you are laying them. The helper will make a good cut man in the process also. To set each tile properly, use a rubber mallet and a wood block to gently tap each one into the mastic. If you have to replace one that breaks, add some mastic to the back of the new tile before placing it in position.
Use plastic spacers to ensure even spacing for consistent joint. These are removed prior to grouting. A four foot level (or smaller) is used as you go to make sure the tiles are lined properly and set into the mastic at the same elevation (level).
Step Six: Grouting the Joints
After the tile is placed for one whole day it is time to remove the spacers and begin filling the joints with grouting. Grout can be bought in bulk but the premixed grout is easier and faster to apply. Both can be bought in a variety of colors. If you are using a tile that might be unsealed or porous a sealer is needed to keep the grout from sticking to the tiles.
Mix only what you can apply in a half hour. This will prevent the grout from drying before you apply it. Cleaning off the excess as you go is a good idea as well. Use a damp sponge or a rag but be sure not to wet the grout as you do. Wiping diagonally across the joints is the best method to avoid disturbing the fresh grout. Releasing agents are available for use after the grout is completely dry. These will enable you to remove the haze from the tile. A final wipe down with a damp sponge is all that is need after that.