How to Repair Cracked Grout

Grout is the unsung hero of your tiled surfaces, acting as both a visual frame and a critical barrier against moisture. When you spot a crack, it isn't just an aesthetic nuisance; it is an open invitation for water to seep behind your tiles and wreak havoc on the substrate. A well-executed grout repair stops that moisture in its tracks and makes the joint look factory-new again. Successfully refreshing grout requires patience more than brute strength. The goal is to clear out the loose material without chipping the edges of your tiles. Once the channel is clean and dry, fresh grout bonds easily, creating a seamless line that blends perfectly with the existing work. Do this right, and you won't be able to tell where the old grout ends and the new begins.

1. Rake Out Cracked Grout. Use a carbide-tipped grout rake to scrape away the cracked or loose grout. Pull the tool firmly through the joint to clear out at least 1/8 inch of depth.
2. Vacuum and Wipe Clean. Vacuum the area thoroughly to remove all dust and loose particles. Wipe the joints clean with a damp, lint-free cloth to ensure the new grout can bond properly.
3. Mix Grout to Peanut Butter. Mix your matching grout powder with water according to the package instructions until it reaches the consistency of peanut butter. Let it slake for five minutes before giving it a final stir.
4. Pack Joints with Pressure. Use a rubber grout float held at a 45-degree angle to press the mixture firmly into the gaps. Move diagonally across the tiles to ensure the joints are filled completely without pulling the grout back out.
5. Sponge Off Excess Grout. Wait about 15 minutes, then wipe the excess grout off the tile faces with a slightly damp sponge. Rinse the sponge frequently and keep it as dry as possible.
6. Buff and Seal for Protection. Once the grout has dried to a haze, buff the tiles with a clean, dry microfiber cloth. After the grout cures fully—usually 24 to 48 hours—apply a liquid grout sealer to protect it from staining.