Why Does Concrete Sink?

Understanding the unique soil and weather conditions in Illinois that cause concrete settling and what you can do about it.

Understanding Concrete Settling in Illinois

Explore the different factors that cause concrete to sink and settle in Illinois.

Close-up view of cracked concrete showing soil erosion underneath

Concrete cracking and settling caused by soil erosion and instability

Prairie State Clay Soils

Illinois sits on some of the most expansive clay soils in the Midwest. These soils were formed by ancient glacial activity and contain high levels of montmorillonite clay, which can expand up to 10 times its dry volume when wet.

Wet Season Effects:

  • • Soil expands and pushes against foundations
  • • Hydrostatic pressure increases
  • • Surface water infiltration increases

Dry Season Effects:

  • • Soil shrinks and creates voids
  • • Concrete loses support and settles
  • • Cracks develop allowing more water infiltration

Regional Weather Patterns

Illinois experiences extreme weather variations that accelerate concrete settling:

Winter:

Temperatures below freezing cause soil to contract and water to freeze, creating pressure and voids.

Spring:

Rapid snowmelt and heavy rains saturate clay soils, causing significant expansion.

Summer:

Hot, dry conditions cause clay to shrink dramatically, creating the largest voids.

The Polyurethane Solution

Polyurethane concrete lifting addresses the root causes of settling by filling voids, stabilizing soil, and providing long-lasting support that won't wash away or compress like traditional materials.

Fills Voids

Expands to fill all voids and gaps under concrete slabs

Waterproof

Won't wash away or deteriorate from water infiltration

Long-Lasting

Provides durable support that won't compress over time

Stop Concrete Settling Before It Gets Worse

Don't let Illinois soil conditions damage your concrete. Contact Pete's Poly Concrete Lifting for a long-lasting solution.