Grundy County, IL Shrink-Swell Risk

What Grundy County, IL's soil means for a foundation

Moderate

USDA's SSURGO data puts Grundy County, IL's soil at "Moderate" shrink-swell potential, an area-weighted linear extensibility of 3.96% across 60.4% of the county's surveyed land. A real but modest amount of movement - standard foundations usually hold up, but drainage and moisture control around the foundation still matter more than on low-risk soil.

This is a county figure, not a lot figure

USDA's survey covers the whole of Grundy County, IL at once, not any single address. A local geotechnical report, typically $1,000-$5,000 (around $2,700 typical), is the only way to know what one lot in Grundy County will actually do.

Report cost vs. repair cost

With Grundy County, IL rating "Moderate", a geotechnical report is still worthwhile before a build, just less urgent than in a high-risk county. 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.

How Grundy County, IL compares

Nationally, Grundy County, IL is the 587-most-constrained of 3,085 rated counties for shrink-swell soil. Within Illinois alone it ranks 33 of 101. Grundy County covers 418 square miles and counts 53,835 residents.

For contrast

Orleans Parish, LA carries this site's most-constrained reading. Clinton County, IL and Jefferson County, MT 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

More of Illinois

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