Foundation Underpinning

The foundation of your home is supported on soil or rock. If this material changes volume for any reason, the foundation may settle and crack. The solution to the problem is to extend the affected foundation down into firm, less compressible material. This process is called "foundation underpinning." There are several techniques available for foundation underpinning. All have advantages and disadvantages. The most cost-effective approach for a particular situation depends on the geology of the site, the type of existing foundation construction and access for completion of the work.

In the Washington, D.C. Metropolitan area, foundation settlement is most frequently caused by the consolidation of poorly compacted fill or volume changes in clays that are affected by changes in their water content. These materials are frequently referred to locally as "marine clays." They are most prevalent in the Potomac River Valley, but may be found in isolated pockets throughout the area.

Some noticeable symptoms of settlement are "stair step" cracks in masonry walls, sloping floors and doors or windows that don’t function properly. The settling process can be arrested and frequently the settled foundation can be re-leveled by the process of foundation underpinning.