How to Replace a Slate Floor Tile

cracked slate tile

PebbleArt Inc.

Project Overview
  • Working Time: 1 - 2 hrs
  • Total Time: 2 - 3 days
  • Skill Level: Intermediate

Although real slate tile is a durable flooring material, it is possible for individual tiles to become chipped, cracked, or otherwise damaged beyond repair. Fortunately, even with as strong and impervious to wear and water as a tile floor is, it's also one of the easiest types of flooring to repair. To replace a damaged tile, you simply scrape out the grout around the tile, break up and chip out the tile, then scrape off the old adhesive (which most likely is thinset, a grout-like mortar adhesive) so you can start over with a clean subfloor surface. 

What You'll Need

Equipment / Tools

  • Carbide-tipped grout saw
  • Hammer
  • Nail set
  • Cold chisel
  • Putty knife
  • Coarse sandpaper
  • 1/4-inch notched trowel
  • Goggles
  • Work gloves
  • Rubber mallet
  • Piece of 2x4 board
  • Small screwdriver
  • Tile spacers (optional)
  • Needle-nose pliers (optional)
  • Cloth
  • Sponge
  • Bucket
  • Shop vacuum
  • Level (optional)

Materials

  • Thinset mortar
  • Replacement tile
  • Tile grout
  • Tile sealant

Instructions

  1. Remove the Old Grout

    Scrape out the old grout around the broken tile, using a carbide-tipped grout saw. Be careful not to chip or scratch the surrounding tiles as you work. Use a gentle but firm motion to remove all of the grout until the side of the tile is completely exposed.

    removing slate grout
    PebbleArt Inc.
  2. Break Up the Tile

    Use a hammer to drive a nail set into the surface of the tile to puncture it in one or two places. This breaks the slate up so that you can remove it.

    Breaking Slate Flooring
    PebbleArt Inc.

    Warning

    No matter how careful you are, shards of stone can fly during this step. Be sure to wear safety goggles and heavy work gloves to protect your eyes and skin from debris.

  3. Remove the Tile Shards

    Place the point of a cold chisel into one of the cracks and lightly tap the chisel with a hammer to loosen and pry up the pieces of the tile. Chisel very carefully near the edges of the tile to prevent damage to adjacent tiles. Break up just the tile and old mortar layers, being careful not to damage the subflooring or tile backer material below. 

    remove slate tile
    PebbleArt Inc.
  4. Remove the Old Adhesive

    Scrape away the old adhesive with a putty knife or cold chisel. Remove as much of the adhesive as possible, then use coarse sandpaper to remove residual adhesive and smooth the area. Remove all grit and dust from the floor with a shop vacuum. 

    apply tile adhesive
    PebbleArt Inc.
  5. Place the New Tile

    Mix a small batch of thinset mortar as directed by the manufacturer. Apply mortar directly to the back of the tile, using a 1/4-inch notched trowel. Drag the notched edge of the trowel through the mortar to make even ridges. Make sure that the entire bottom surface of the tile is covered. 

    Set the tile in place on the floor and press it down until its surface is level with the surrounding pieces. You can twist it slightly back and forth to get it to sit down into the mortar. If desired, place a tile spacer at each of the four corners to ensure that your grout lines will be straight. Otherwise, simply align the tile by eye so the grout line is all the same width.

    apply the tile adhesive
    PebbleArt Inc.
  6. Tap Down the Tile

    Lay a straight piece of a 2x4 board across the newly placed piece so that the board touches at least two adjacent tiles. Tap the board lightly with a hammer or mallet to press the new tile down so that it rests even with its neighbors. You can also use a level to ensure that you have the tile flush.

    In the case of cleft slate, the surface of the tile may be irregular, making it impossible to get it perfectly even with the rest of the floor. Focus on getting the edges of tiles such as these even with adjacent pieces along the grout line.

    tap down the slate flooring tile
    PebbleArt Inc.
  7. Clean Up the Work Area

    Use a small screwdriver to remove excess adhesive from the spaces around the tile. Wipe any smeared mortar from the tile surfaces with a damp cloth. If you used spacers, use a pair of needle-nose pliers to carefully remove them. Let the tile set for at least 24 hours. 

    cleaning the tile installation
    PebbleArt Inc.
  8. Grout the Tile

    Mix a small batch of grout as directed by the manufacturer. Apply the grout to the space around the tile, using a putty knife. You can also use your fingers to force the grout down into the gaps. Wipe off any excess that gets on the surface of the tiles with a cloth.

    When the grout does not yield to light finger pressure, carefully wipe over the grout lines with a wet sponge to smooth the grout and clean the tile surface. Rinse the sponge frequently in a bucket of clean water. It's fine if the grout leaves a haze on the tile surface. Let the grout dry overnight and seal it in the morning following directions on a good-quality grout sealer. Wait about an hour for the grout sealer to dry before moving on to the next step.

    Grout the tile
    PebbleArt Inc.
  9. Clean and Seal the Floor

    Clean the entire surface of the floor with warm water, making sure that you remove all dirt and debris. Allow the floor to dry thoroughly.

    Apply a commercial-grade below-surface natural stone sealer to the entire floor as directed by the manufacturer. The sealer will soak into the stone, creating an invisible barrier and making the individual tiles shimmer with enhanced color. This will help to blend the new piece into the rest of the installation.

    Clean and sealed tile
     PebbleArt, Inc.