There are two main approaches for major foundation crack repair. The first is to fill the crack (or cracks) with fresh concrete. The second is to lift the sagging foundation, when the sagging foundation is the reason for the development of the cracks. Here is how each is completed and how your concrete contractor decides which repair option is best for your particular needs.
Filling the Cracks
One of the first things your contractor will do is ask to see your basement (if you have one). He or she wants to see if the cracks in your foundation go all the way down the basement walls and see if the cracks are rather severe. If the cracks are minor or if the cracks do not extend beyond the surface level of the soil around your home, it is possible that filling the cracks is all the repair work your home needs right now. If you and your contractor come to this agreement, then he or she and his/her crew will mix the concrete and use masonry trowels to fill and patch the cracks. Any cracks that can be seen from inside the home along your basement wall are also filled/patched.
Lifting the Sagging Foundation
A sagging foundation can be the result of sandy or loamy soil, shifting earth, earthquakes, etc. The only way to diagnose a sagging foundation is to check the basement walls. The cracks caused by a sagging foundation will have fairly wide split spaces. Often, the cracks travel from the top of the foundation walls above ground to the base of the foundation walls below ground. Additionally, if the foundation is sagging, sinking and causing cracks and splits, it can also cause the walls in your home to crack and split if the sagging problem is quite severe.
To lift the foundation and re-align the walls, an area around your home has to be excavated and then steel girders help lift the sagging foundation back into place. These girders act as braces, bolstering the walls and preventing them from sliding back down again. You may still need some patch repair for aesthetic purposes after the process is complete, but it is considered a very permanent solution to what could otherwise be an ongoing problem.
Deciding Which Crack Repair Is Best
You and your contractor will have to examine the cracks, the types of soil surrounding your home, and any other damage co-occurring within your home to determine which type of repair is best. If you notice anything else out of the ordinary (e.g. doors that do not close and swing open awkwardly, cupboards with the same closing and swinging issues, etc.), it is very possible that minor cracks you currently see are the start of a more serious problem with your foundation. Examining all of these factors helps determine if you should lift the foundation or just patch it for the time being.