Why Foundation Settling Often Gets Worse in Cooler Months

  The Freeze-Thaw Cycle

The most significant cause of foundation damage in cooler months is the freeze-thaw cycle. This is a repeated process where temperatures fluctuate above and below freezing.

• Freezing and Expansion: When water from fall rain or melted snow seeps into small cracks and gaps in the soil around your foundation, it freezes and expands. As water turns to ice, it expands by about 9%, creating an immense amount of pressure against your foundation walls. This force can cause existing cracks to widen and new ones to form.

   
   

• Thawing and Contraction: When the temperature rises, the ice melts, and the soil contracts. This leaves behind a void where the foundation was once supported. The sudden loss of support can cause the foundation to shift or settle into the newly created gap.

   
   
   

This cycle of swelling and shrinking soil puts continuous stress on the foundation, gradually undermining its stability.

Hydrostatic Pressure from Rain and Snowmelt

While dry weather can cause soil to shrink, periods of heavy autumn rain and winter snowmelt can saturate the soil. This creates hydrostatic pressure, which is the force of water pressing against your foundation walls.

After a long, dry summer, the soil around your home may be parched and cracked. When a heavy fall rain or a sudden snowmelt occurs, the soil absorbs a large volume of water quickly. This sudden absorption causes the soil to swell rapidly, putting an immense amount of pressure on your basement walls and leading to horizontal or stair-step cracks.

The Role of Expansive Clay Soil

The specific type of soil found in the Midwest contributes significantly to these seasonal problems. Expansive clay soil absorbs a large amount of moisture when wet and shrinks dramatically when dry.

During a dry summer, the soil shrinks and pulls away from the foundation. When fall and winter precipitation comes, the soil quickly expands. This repeated process of swelling and shrinking—or "shrink-swell" behavior—is a primary cause of foundation damage and can make existing issues much worse in the cooler months.