By Shawn Kyles
When a concrete foundation is poured, small cracks can appear as the cement dries and shrinks. Shrinkage cracks are vertical and extremely small. They typically appear on foundation walls, but do not affect the structural integrity of the home. Settlement cracks are a more serious problem. Unlike shrinkage cracks, they will often extend into the structure, weakening the building.
Most houses experience some degree of settlement (downward movement) after they have been built. Additional and more severe sinking can occur if the home was constructed on poorly compacted soil, or when the building’s weight compresses the soil beneath it.
Foundation settlement can also be caused by frequent or dramatic changes in the soil’s moisture content. When soil becomes wet, it expands. As it dries, it contracts and loses its volume, creating more space for the foundation to drop further into the ground. These moisture issues often come about from plumbing leaks, excessive rain and poor drainage.
Settlement can also take place when the roots from trees and foliage planted near the home absorb too much water from the soil. A poorly designed house or foundation can result in too much settlement as well.
If the settlement is uneven or extensive, the foundation will become stressed and start to crack. Large cracks generally appear due to continuing motion that occurs over a long period of time. Foundation cracks will not only weaken the structure, they make it easier for water to enter the building. Water seepage can further damage the home, in addition to causing potentially serious health issues due to mold and mildew buildup.
There are several methods that can be used to repair foundation cracks, including filling the cracks with bonding agents that create a waterproof seal. When addressing the problem, it is also important to discover what is causing the cracking. Correcting the underlying issue will prevent the situation from reccurring.
An experienced foundation repair expert can inspect your home for cracks and determine if there are any foundation problems that need to be addressed. In earthquake zones, regular foundation inspections and maintenance are essential. During a quake, a structure that has been weakened by cracks and water seepage can cause building walls to crumble or even the entire home to collapse. Keeping your foundation in good condition will prevent further damage and the need for more costly repairs. It will also help maintain the value of your home.