How to Seal Concrete Wall Cracks
- 1). Ensure the crack is dry before proceeding. Clean the area vigorously with a wire brush to remove any dirt, loose concrete or paint.
- 2). Drive 3-inch (10d) finishing nails into the entire length of the crack with a spacing of 12 inches on center. Drive them only partway into the crack.
- 3). Open up the two containers of epoxy crack sealer that came in your liquid concrete repair kit. Mix a small amount of the two parts together on a board until the mixture is uniform in color.
- 4). Coat the flange of the injection port with the mixed epoxy crack sealer, slide the flange over a nail and press it to the wall. The injection port also came as part of your liquid concrete repair kit. The injection port is a nozzle that will be used to fill the crack with the liquid concrete repair epoxy. The flange allows mounting to a wall; the other end will receive the injection from the liquid concrete repair tube. Repeat this step for each additional nail.
- 5). Mix another batch of epoxy crack sealer. Spread a 1/8-inch-thick, 2-inch-wide coating over the entire length of the crack with your putty knife. Also, spread it around each of the flanges of the injection ports. Allow the epoxy to cure for eight to 10 hours.
- 6). Mix the liquid concrete repair epoxy (another component in your kit) in the tubes with the plunger rod that came with the kit. Insert the tube into the caulk gun and place it on the lowest injection port. Pump the liquid concrete repair epoxy into the injection port until you begin to see it ooze out from the port above.
- 7). Insert the plug that came in your liquid concrete repair kit into the injection port you just filled with epoxy and move up to the next injection port. Fill this one with epoxy until it oozes from the port above. Repeat this process until you have filled all the injection ports.
- 8). Let the epoxy cure for five days. Cut off the injection port necks with a hacksaw and discard. If desired, mix more of the epoxy crack sealer together and fill these holes.
