Why do foundations fail?

A failing foundation can lead to cracked walls, roofing problems, uneven floors and a variety of other issues, depending upon the severity of the foundation failure. This is why it is so important to address any foundation problems right away. Foundation problems are more common than you may think. What causes foundation problems can be attributed to many factors.

 

The following are some of the causes of foundation failure:

Common causes and effects of foundation movements in residences

 

Soil Related Conditions
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Figures 1 & 2  The impact of swelling soils on a residential structure can be quite dramatic. If subgrade soils swell beneath exterior footings or interior floor slabs, excessive structural distortion and cracking can occur.
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Figure 3  A discrete prism of soil provides the ultimate structural support for a footing system. If this soil is not acceptable, it must be removed and replaced with an engineered soil material that provides suitable load support with minimal vertical settlement. Figure 4  The development of frost lenses below foundations and floor slabs can cause an upward movement of support soils, leading to cracking and distortion.
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Figure 5  A layer of compressible, uncontrolled fill can lead to unacceptable settlement of a residential structure. Figure 6  Fills of varying thickness beneath a structure often result in a situation where differential movement of a foundation system occurs.
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Figure 7  Inadequate control of subsurface and surface water does not allow for the rapid trasmission of collected water (rainfall and groundwater) from downspouts and sump pump discharge pipes away from the residence. Figure 8  Significantly inadequate drainage along a foundation wall can lead to major heaving of clay foundation soils as the clay becomes saturated.