DuPage County, IL Shrink-Swell Risk

Shrink-swell potential in DuPage County, IL

Moderate

Soil across 42.8% of DuPage County, IL comes back "Moderate" in USDA's shrink-swell data, averaging 4.29% linear extensibility. That's a middle reading: not the sharp swings that crack a foundation outright, but enough that grading and drainage are worth getting right.

What this number does and doesn't tell you

This is a countywide, area-weighted figure across every soil survey map unit in DuPage County, IL - never a reading for one specific parcel. A site-specific soil report, usually $1,000-$5,000, is what an engineer would actually pull before designing a foundation on a lot in DuPage County.

DuPage County: the real numbers

DuPage County's soil reading points toward standard foundation practice as the likely outcome, not the exception. A geotechnical report runs $1,000-$5,000, typically around $2,700. Foundation repair, if a specific lot turns out to differ from the county average, runs $5,000-$15,000.

Where this sits nationally

Among the 3,085 rated counties on this site, DuPage County, IL ranks 440 most-constrained nationally, and 14 of 101 within Illinois. DuPage County covers 328 square miles and counts 937,142 residents.

See how another county compares

Orleans Parish, LA carries this site's most-constrained reading. Schuylkill County, PA and San Miguel County, NM are worth a look for comparison.

How this reading is built, and its real limits · Moisture management: the cheap fix that works on any soil

Elsewhere in Illinois

Every county in Illinois is on this site, including Douglas County, IL and Fayette County, IL. The full underlying dataset is downloadable directly, one row per county.