How do you repair a flagstone patio?

Repair a flagstone patio by lifting the broken flagstone from the patio and scrubbing the surface underneath. Apply masonry adhesive and set the piece back into the patio. Fill in holes with adhesive and allow to dry.

Thanks to masonry adhesive, there is no need to use mortar on a piece of broken flagstone. The process to fix broken flagstone is easy and inexpensive. Follow the steps below to complete the project.

1. Remove the broken flagstone

Gently lift out the piece of broken flagstone from the patio.

2. Clean the area underneath

Clean the surface underneath the flagstone with a wire brush. Wipe it clean with a dry sponge. Use an air compressor to blow away any remaining dirt and debris.

3. Apply the adhesive

Apply the adhesive in a continuous bead across the entire surface of the broken flagstone. Space each bead no more than one inch apart to ensure even coverage.

4. Smooth the beads

Smooth the beads across the entire surface of the flagstone using a flat jointer.

5. Apply more adhesive

Apply adhesive around the perimeter of the flagstone.

6. Set the flagstone back down

Set the flagstone back into place, pressing it firmly into the adhesive.

7. Clean the surface

Clean the surface of the flagstone with a damp rag, removing any adhesive.

8. Fill in the spaces

Fill in any spaces around the perimeter of the flagstone with mortar-joint repair adhesive. Smooth with a flat jointer.

9. Conceal the repair

Conceal the repair by sprinkling stone dust and sand over the wet mortar repair adhesive. Let sit overnight.

10. Clean the area

Sweep the sand off the area after allowing to sit overnight.

Wait at least four days before walking on the repaired flagstone.