How do I Repair a Cement Block?

Repair cracks in your concrete block wall.

Concrete blocks are typically appear in basement foundation walls. They are sturdy and will last for a long time. Water can damage them and once you notice a crack in your concrete blocks it is important to fix it as soon as possible to avoid further deterioration. The method of fixing a crack depends partially on how large it is. Larger cracks require a more heavy duty repair, whereas you can easily repair smaller cracks with a caulk filler.

Things You'll Need

• Wire brush
• Garden hose
• Chisel
• Hammer
• Concrete patch kit
• Trowel
• Concrete caulk
• Caulk gun
• Paintbrush
• Concrete sealer

Instructions

1. Rub the surface of the concrete block with a wire brush. Rub in all directions to work off any loose concrete. If possible, spray the surface of the concrete block with a garden hose to remove any dirt.

2. Place a chisel inside the crack, if the crack is large. Angle the chisel towards the bottom corner of the crack. Tap the back of the chisel with a hammer. Chip away at the crack until the base of the crack is wider than the opening.

3. Mix a concrete patch. Read the manufacturer's directions to properly mix the patch. Use a small trowel to apply the path to the crack. Push the patching mix all the way into the crack.

4. Repair a small crack using concrete caulk. Place the caulk into a caulk gun and cut off the tip with a scissors. Insert the tip of the caulk into the crack as far as it will go and squeeze the trigger on the caulk gun.

5. Allow the patching concrete or the concrete caulk to dry according to the manufacturer's directions. Once dry, paint a concrete sealer over the repair.

References

• Ask the Builder: Concrete Wall Repairs & Concrete Epoxy; Tim Carter