Living With Expansive Soils

The effects can be dramatic if expansive soils supporting structures are allowed to become too wet or too dry.

Patios, driveways and walkways may crack and heave as the underlying expansive soils become wet and swell.

Sometimes the cracking and heaving appear temporary as the soils dry and shrink back to their original position.

However, footings can behave differently. The concentrated weight of the structure will inhibit the soil's upward expansion. Outward expansion on the other hand may continue. The footings will not be returned to their original position as the soils dry and shrink. Instead, they can "ooze" down to a slightly lower level. This process can accumulate if the wetting and drying is allowed to continue season after season, year after year
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