by John Shaggy

Created on: April 08, 2010

If you own a home, chances are that you have a basement or foundation underneath it to support the weight of your home.  While having a basement and a foundation are definitely good things to have, cracks in the foundation are unsightly and present a structural hazard to the home itself if not repaired.

There are several different reasons that a foundation can begin to crack.  Homes settle and shift every year from changes in ground temperature and from excessive moisture in the ground next to the foundation.  Repeated shifting and moisture throughout the years can weaken and damage the foundation until the cement starts to crack under the strain and over time, the cracks will become larger and wider if the foundation is not repaired.  Before we talk about repairing the foundation, here is an example of what not to do if you do notice cracks forming.

Do not use a silicone sealant or caulk to fill the crack!  Silicone may stop water leakage but will also trap moisture in the cement surrounding it and over time, the cement will weaken and eventually disintegrate.  When this occurs, your silicone quick fix will backfire on you and you now have a major structural repair job instead of a simple crack to worry about.  To seal foundation cracks the best material to use is good quality hydraulic cement with superior tensile strength.

Patching and repair of your foundation involves a series of steps to follow.  The following method is a personal favorite and one found through a series of trial and error.

1.  Start by grinding away all paint from the crack.  Use a ½-inch drill with a coarse wire wheel attachment for removal of old paint and silicone.

2.  After grinding off away all paint and silicone, wash down the area around the crack with a bleach/water mixture to remove all grinding   dust left by the wire wheel.

3.  After the wall dries, use Lime Away bathroom cleaner to remove remaining residue.  After applying the cleaner, use a small wire bristle brush to remove any remaining loose residue and let dry overnight.

In the interest of saving your skin and your eyes, always wear gloves and eye protection for any of the procedures described here and take any other safety precautions necessary as well.  A dust mask is a necessity for grinding.  Always, always work in a well-ventilated area and keep a fan on to improve ventilation in the work area as well.

After surface preparation is complete, proceed to get the cement ready to patch the foundation crack.

 When mixing cement to patch your foundation, the cement manufacturer will have mixing instructions for you to follow, but remember that these instructions are only guidelines and not necessarily correct.  When mixing your cement, mix only what you can use and as a general rule of thumb, the cement should be the consistency of putty for application.  Once the proper consistency is reached, use a mason's trowel or a putty knife to seal the crack.  If you have a deep crack, its not a bad idea to use a shim or other narrow tool to force the cement into the crack as far as possible, insuring a good, watertight seal against moisture.  Repeat the process until you have a level surface that matches the rest of the wall and your crack is now sealed and ready for painting.

Keep in mind that an ounce of prevention may be worth a pound of cure when patching a foundation crack and well worth your time and effort to prevent future problems.

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