Concrete and Expansive Clay Soils on the Front Range

Much of the Front Range sits on clay that swells when wet and shrinks when dry. That movement can lift, tilt and crack slabs unless the project is planned for it.

Why Clay Moves

Clay soil absorbs water and swells, then shrinks as it dries. Slabs that rest on it can rise and fall with the seasons.

Water that collects next to a slab makes the effect worse.

What Helps

A good base of compacted gravel, careful grading and drainage that moves water away from the slab all reduce movement. Reinforcement and well-placed joints help control cracks.

Keeping downspouts and sprinklers from soaking the soil near a slab matters too.

When to Get Advice

If a slab has already moved, the cause matters before any repair. We look at drainage, base and soil and talk through options.

For new slabs, a short site visit can head off problems.