How to Repair a Concrete Swimming Pool

Repair small cracks to keep your pool in shape.

If you live in an area with freezing and thawing during the winter or an area with shifting ground, your in-ground concrete swimming pool may develop cracks over time. While small, hairline cracks occur in almost all types of concrete regardless of your location, larger cracks may indicate a structural problem that requires professional help. If you just have small cracks, perform the repair as a do-it-yourself project.

Things You'll Need

• Grinder or saw
• Hammer
• Chisel
• Brush
• Silicone caulking
• Caulk gun
• Pool patch material
• Trowel
• Sponge

Instructions

1. Drain your swimming pool so the water line is below where you need to repair. If the swimming pool repair is near the top of the pool rim or on the swimming pool coping, you may not need to drain it. If you don't drain the pool, keep concrete debris out of the water and the pool's drainage system.

2. Remove the concrete on either side of the crack, using a grinder or saw with a diamond blade. Create a cleared area at least ½ inch wider than the crack and 1 inch longer with straight edges for best results. If you are repairing concrete swimming pool coping, you may be able to remove the precast concrete bullnose coping and reuse it. Remove the old mortar or plaster from the coping as gently as possible with a hammer and chisel.

3. Remove all dust and debris from the area you are fixing, using a brush. Allow air to get into the opening to dry it thoroughly.

4. Lay a bead of silicone caulking ¼ inch inside the opening you created, using your caulk gun. This provides an additional waterproof barrier to the substrata of the swimming pool.

5. Mix enough pool patch material to fill the hole. The patch material is ready for spreading when it's the consistency of peanut butter. Add color additives as needed to match your pool's color.

6. Push the pool patch material into the opening with your trowel. Work it firmly into the opening. Remove any bubbles. Cover the caulking bead with pool patch. Make sure the pool patch is smooth with the existing pool surface. If you are reusing bullnose edging, use the pool patch material to set the cleaned pieces. It can act as the mortar to fill the spaces between them as well.

7. Tamp a wet sponge over the damp pool patch to give it the same consistency as the pool's surface. Allow the pool patch to dry.

8. Refill the pool as soon as the repair is complete.

Tips & Warnings

• Wear safety goggles and work gloves for this project.

• Be careful using electrical power tools around the water.

References

• Ask Alan a Question: Pool Crack Repair Information
• Pool Center: Surface Repairs