Clay Risk Score by Location
About 60 seconds- Leave knowing your property's specific clay soil risk level and what it means for your foundation
Clay soil composition varies block by block across the Kansas City and Des Moines metro areas. The type of clay beneath your home determines how much the soil expands when wet and contracts when dry. That expansion-contraction cycle is the primary force that damages Midwest foundations. This tool uses USDA soil survey data for your specific location, combined with your home's age and foundation type, to calculate a composite risk score from 1 to 10.
Knowing your risk level changes how you interpret what you see. A hairline crack in a low-risk area is probably cosmetic. The same crack in a high-risk area may be the beginning of progressive settlement. Context matters, and this score provides that context.
Different regions have different clay soil compositions
Older foundations used different construction standards and have had more exposure to soil movement
Some foundation types resist clay soil movement better than others
Have you noticed any of these? (Check all that apply)
Current symptoms help calibrate your overall risk level
Your Clay Risk Score
Score Breakdown
What Your Score Means
Lower Risk
Your soil conditions and home profile suggest below-average foundation stress. Minor cosmetic cracks are common and usually not structural. Standard maintenance — keeping gutters clear and grading away from the foundation — is typically sufficient. Recheck if you notice new symptoms or after major weather events.
Moderate Risk
Your combination of soil type, home age, or foundation construction puts you in the middle range. Existing cracks deserve monitoring — measure and photograph them seasonally. Drainage improvements and moisture management around the perimeter can reduce the forces acting on your foundation. If cracks widen beyond 1/4 inch or doors begin sticking, consider professional evaluation.
Higher Risk
Your property sits in conditions where foundation movement is more likely and may already be underway. Active symptoms at this risk level — stair-step cracks, wall bowing, floor slope — warrant professional evaluation sooner rather than later. A structural engineer ($400–$800) provides an objective assessment independent of any repair company. Early intervention at this tier typically costs less than waiting.
How the Score Is Calculated
The Clay Risk Score combines four factors: local soil conditions (based on USDA soil survey data for your metro area and suburb), housing era (older homes have endured more cycles of soil movement), foundation construction type (block basements are more vulnerable than poured concrete), and current visible symptoms (which indicate whether soil forces have already produced structural effects).
Kansas City properties start with higher soil risk than Des Moines properties because the Wymore-Ladoga clay complex underlying most of the KC metro carries a USDA "very high" shrink-swell rating with 60–80% clay content. Des Moines' glacial till has moderate shrink-swell potential but persistent hydrostatic pressure. Both create foundation risk — through different mechanisms.
How This Connects
The clay risk score is one piece of a larger picture. To understand why clay content matters and how shrink-swell cycles actually move foundations, read the foundation science overview. For a step-by-step walkthrough from identifying symptoms to choosing a repair method, the complete homeowner guide puts the risk score in context alongside everything else you need to know.