Water is the main enemy in reactive soils causing them to either shrink or swell

If all the soils beneath a foundation shrink or swell uniformly, it is unlikely to cause a problem. But when only part of the foundation heaves or settles, differential movement causes cracks and other damage.

Most differential movement is caused by differences in the moisture content of the soil. After construction, soil beneath part of the foundation becomes wetter or drier than the rest of the soil.

Here is why this happens:

Soil Composition

Glacial Till soils prevalent throughout New England tend to consolidate or erode with the presence of water causing settlement which may produce cracks throughout the structure.

Transpiration

Tree roots may desiccate the soil beneath a home causing the soil to shrink and the home to settle.

Plumbing Leaks

Water from plumbing leaks is often a cause of foundation problems.

Drainage

Improper drainage is a leading cause of foundation failure. Excess moisture will erode or consolidate soils and cause settlement.

Inferior Foundation Construction

Insufficient steel and inferior concrete will contribute to movement in the slab.

Inferior Ground Preparation

Soft, low density soils and/or improperly compacted soils beneath a home is the leading cause of foundation failure. Cut and fill situations should be properly prepared before the soil is ready to support a structure.