Madison County, AL Shrink-Swell Risk

What Madison County, AL's soil means for a foundation

Low

USDA's SSURGO data puts Madison County, AL's soil at "Low" shrink-swell potential, an area-weighted linear extensibility of 2.7% across 70.7% of the county's surveyed land. That's the easiest starting point on this site's scale - a standard foundation is the reasonable default here, though any one lot can still differ.

This is a county figure, not a lot figure

USDA's survey covers the whole of Madison County, AL 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 Madison County will actually do.

Report cost vs. repair cost

With Madison County, AL rating "Low", 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.

Where this sits nationally

Nationally, Madison County, AL is the 1,404-most-constrained of 3,085 rated counties for shrink-swell soil. Within Alabama alone it ranks 15 of 67. The county spans 802 square miles, home to 423,355 people.

Before you act on this

Orleans Parish, LA carries this site's most-constrained reading. Gasconade County, MO and Motley County, TX 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 Alabama

Every county in Alabama is on this site, including Calhoun County, AL and Chambers County, AL. The full underlying dataset is downloadable directly, one row per county.