1 out of 5EasyNo masonry skill required
About $10 to $20
10 to 20 minutes per flagstone
In this video, This Old House landscape contractor Roger Cook shows a no-mortar way to fix a mortared walkway.
Repairing a flagstone walkway
- Lift the loose flagstone from the walkway.
- Scrub the surface below the flagstone with a wire brush to remove all dirt and mortar.
- Wipe the surface clean with a dry sponge.
- Use an air compressor fitted with an air nozzle to blast away any remaining dirt or dust from all cracks and crevices.
- Apply a continuous bead of masonry adhesive back and forth across the entire surface. Space the beads no more than 1 inch apart.
- Smooth and flatten the adhesive beads with a flat jointer.
- Apply a bead of mortar-joint repair adhesive around the perimeter of the flagstone.
- Set the flagstone back into the walkway, pressing it down into the adhesive.
- Clean surface of the flagstone with a damp rag or sponge.
- Fill in any voids or holes around the perimeter of the flagstone with mortar-joint repair adhesive. Smooth the adhesive with the flat jointer.
- To help conceal the repair, sprinkle a mixture of stone dust and sand over the wet mortar-joint repair adhesive.
- The next day, sweep off the stone dust and sand.
- Wait four or five days before walking on the repaired flagstone.
- Use the remaining mortar joint repair adhesive to fill in any cracks or holes in the walkway.