When a slate floor tile gets cracked or damaged, it is wise to replace the damaged slab rather than just repair the cracked part with an epoxy sealer or grout. Aside from looking unsightly, patched-up tile will eventually fall into pieces. Here's how to remove and replace a damaged slate floor tile by yourself.
Measure the damaged tile and purchase a replacement. It is very hard to find the exact cut and size. Since slate is a natural stone, no single stone can be cut in the same way. What you can do to lessen the effort of trimming down a replacement tile is to find a slate tile within this size range: the exact size of the damaged tile, or a centimeter smaller (maximum) on all sides, or an inch thicker (maximum). But if you can't find any tile within the mentioned size range, you can opt for a slate tile twice as large as the damaged tile and cut it with a diamond blade wet saw. It is easier to cut a larger slab, as it gives enough room for cutting. If you don’t have experience in cutting slate, you can have a professional do the job.
Purchase grout mix in a color that matches the color of your old grout. Get a sample by chipping a small portion of the old grout and presenting it to the hardware store clerk to help you find an exact match.
Remove the Damaged Tile
Using a light hammer and a thin chisel, remove the grout around the damaged tile. When the four sides are free from grout, chisel away the stone from its back. If the stone won’t budge, chisel the stone from the center until it chips away.
If the old stone was installed with a mortar, chip away the remaining mortar on the space, but if with adhesive, sand the remains to even it out.
Install the Replacement
Hammer out small holes in the space using a chisel or a nail. This is to roughen up the floor to create surface friction between the floor and the slate tile.
Apply tile adhesive on the stone. Let it dry for two minutes before installing it in place. Tape the installed tile with masking tape to help hold the tile. Let it dry overnight.
Grout the Tile
Mix the grout in proportions indicated by the manufacturer. Remove the masking tape on the tile. With a rubber float, apply the grout at a 45-degree angle to fill in the voids with grout completely. Use a wet sponge to remove excess grout. Wipe the floor dry with a clean cloth.
Seal the Tile
Smooth out the edges with sandpaper. Apply several coats of stone tile sealer to protect the slate from moisture and abrasion. You may use a spray-on or a brush-on sealer. Some stone sealers can also be used to seal the grout.