Polyurethane Foam Injection


It is almost inevitable that overtime walls and foundations will develop cracks. These cracks are sometimes caused by wet conditions or simply leveling issues into the foundation. To fix these cracks, there are many methods, but the one we are going to talk about here is polyurethane foam injection. This type of repairing is cheap and it can guarantee a long-lasting effect. The injected foam goes through the crack in the soil behind the wall and makes sure to support the wall to not develop further cracks. This fixing method is done from inside of the wall only.


To begin you have to make sure that there is no loose debris in the area of the wall where you are going to repair. With that being said, you should clean the place where the crack is and make sure that the crack is neither wet nor leaking. To clean any loose debris you must use a wire brush and scrub the crack from the bottom to the top. Then you can clean the crack with a damp sponge.

Placing the Injection Ports

You should mark the crack every four inches because that is where you are going to place the injection ports. The tighter the crack, the closer must the injection ports be with each other. Separate the plugs from the injection ports to have them ready. Put some epoxy paste on a piece of cartoon and with a brush put some poxy paste on each side of an injection port. Make sure the hole of the injection port is open and then place it on the marked area. Apply this method for every port and make sure to cover every marked area on the crack. Leave the injection ports to cure for fifteen minutes

Covering the Crack

Now that you have placed the injection ports with the help of the poxy paste it is time that you cover the crack to avoid any leakage of the foam. Start by mixing some poxy paste on a piece of cartoon and then with the help of a brush start applying the paste on the crack. You want to make sure that you cover every area of the crack to avoid any leakage. Don’t be afraid to cover the necks of the injection ports also. This will make sure to keep them in place while you inject the foam.

Injecting the Foam

Take off the plug from the foam container and place the container on the caulking gun. Put the tip of the container on the first injection port and start applying pressure slowly. You don’t want to go too fast because you have to give time to the crack to absorb the foam. While you are applying the foam keep an eye on the second injection port. When the foam starts leaking from the second injection port, that’s a sign that you must stop with the first one and start injecting the foam with the second one. Make sure to put the plug on every injection port when you are done with each of them to avoid leakage.