Franklin County, IL Shrink-Swell Risk

Franklin County, IL's soil, for shrink-swell risk

Moderate

Franklin County, IL: USDA's soil survey rates 50.5% of the county "Moderate" for shrink-swell potential (3.31% linear extensibility). Conventional foundations are the reasonable expectation here, with routine moisture-control practice rather than special engineering.

What Franklin County's reading doesn't cover

Two lots a mile apart in Franklin County can carry different soil, even though they share one countywide reading. A local geotechnical report, typically $1,000-$5,000 (around $2,700 typical), is the only way to know what one lot in Franklin County will actually do.

What it costs to find out, versus to ignore it

With Franklin 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 Franklin County, IL compares

Nationally, Franklin County, IL is the 966-most-constrained of 3,085 rated counties for shrink-swell soil. Within Illinois alone it ranks 80 of 101. Franklin County, IL is 409 square miles with a population of 37,033.

Before you act on this

Orleans Parish, LA carries this site's most-constrained reading. Essex County, NJ and Decatur County, IN 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 Macon County, IL and Madison County, IL. The full underlying dataset is downloadable directly, one row per county.