How to Fix an Exterior Crack

Foundation Crack Repair

• 1

  Locate the exact spot of the crack. If your basement is flooded, there is almost always a crack in your foundation.

• 2

  Place the nozzle of the polyurethane foam canister into the opening of the crack. If the foam canister came with a straw, use it to get down further into the crack.

• 3

  Squirt the polyurethane foam into the crack. The polyurethane liquid will react with any moisture inside the crack and begin expanding and foaming until it seals the crack. Chip off any excess foam from the surface of the foundation with a screwdriver or a chisel.

Concrete Surface Crack Repair

• 4

  Install a diamond-tipped blade into a circular saw. Put on safety glasses, a dust mask and work gloves.

• 5

  Cut a groove that is 1/2 inch deep along each side of the crack. The grooves should run parallel to the crack.

• 6

  Chip out all of the concrete material out of the crack and grooves with a mallet and a cold chisel. You should be left with an even channel that is free of any jagged edges. Vacuum out any dust or small particles.

• 7

  Clean out the groove with a pressure washer. Allow to dry completely before proceeding.

• 8

  Mix up a bag of concrete in a wheelbarrow or tub, according to the product instructions. Use a trowel to fill the groove with the concrete. Fill the groove until it is about 1/2 inch from the surface. Allow the concrete to cure for two to three days.

• 9

  Pour concrete resurfacing powder into the top of the groove. Smooth and even out the powder with a floor squeegee.

• 10

  Slowly add water to the resurfacing powder until it becomes thick in consistency, much like pancake batter. Scrape the resurfacing material over the entire top of the groove. Smooth it out again with the squeegee, then allow to cure.