Hollow Tile Repair

Locate loose or hollow tiles and mark them accordingly. Tap the tiles with a broomstick to identify loose or hollow tiles. Loose tiles resonate when tapped with a broomstick.

Drill holes evenly space holes in the grout joints surrounding the loose tile about every 4 inches. A power drill equipped with a masonry bit works nicely. Use a drill bit with a diameter smaller than the width of the grout joint to avoid damage to the surrounding tiles. Drill only deep enough to penetrate the grout joint. Do not drill into the slab or substrate. Remove dust and debris after drilling the holes using a vacuum.

Load a caulk gun with a tube of tile bonding compound and cut the tip of the tube with a utility knife to a size that allows it to penetrate the drilled holes.

Fill each hole with the bonding compound. Insert the tip into the hole and squeeze the trigger while applying steady downward pressure. A slight amount of resistance is to be expected when injecting the compound. Lightly tapping on the tile surface with a rubber mallet helps to reduce the resistance and allow the material to flow underneath the tile.

Wipe away excess bonding compound with a damp sponge.

Position a 30-pound weight on top of each repaired tile for a minimum of 10 hours to allow the compound to set.

Dig out a small amount of bonding compound from the drilled holes using a utility knife to provide room for new grout.

Repair the holes by filling with the appropriate type and color of grout.