How to Repair a Loose Bathroom Floor Tile

Grout lines act as the first line of defense for your bathroom floor, but once they crack, water inevitably works its way underneath. A loose tile isn't just a noisy nuisance underfoot; it is an open invitation for subfloor rot and mold growth. Addressing the issue early prevents a minor localized repair from turning into a full floor demolition. Done well, this repair makes the tile indistinguishable from the rest of the floor. The secret isn't fancy equipment, but rather patience in clearing the old bonding agent and ensuring the substrate is clean and dry. Once finished, you will have a rock-solid floor that can handle the humidity of a bathroom for years to come.

1. Clear the Grout Lines. Use a carbide-tipped grout saw to carefully remove the grout surrounding the loose tile. Work slowly to avoid chipping the edges of the adjacent tiles.
2. Lift the Tile Free. Gently pry the loose tile upward using a stiff putty knife or a flat-head pry bar. If it feels stuck, use a oscillating multi-tool to cut through any remaining resistance.
3. Scrape Clean Down to Bare. Scrape all old mortar and adhesive from the floor and the back of the tile using a hammer and chisel. The surface must be flat and free of debris for the new bond to hold.
4. Spread Fresh Mortar Bed. Mix a small batch of polymer-modified thin-set mortar and apply it to the subfloor using a notched trowel. Use a notched trowel to create ridges that will collapse when the tile is pressed down.
5. Press Tile Level Firm. Press the tile firmly into the mortar, twisting it slightly to ensure full coverage. Use a level to ensure the tile is perfectly flush with its neighbors.
6. Seal with Fresh Grout. Wait 24 hours for the mortar to cure, then fill the joints with matching grout using a rubber float. Wipe away excess grout with a damp sponge after 15 minutes.