McHenry County, IL Shrink-Swell Risk

Shrink-swell potential in McHenry County, IL

Moderate

Soil across 61.3% of McHenry County, IL comes back "Moderate" in USDA's shrink-swell data, averaging 3.16% linear extensibility. 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.

What this number does and doesn't tell you

This is a countywide, area-weighted figure across every soil survey map unit in McHenry County, IL - never a reading for one specific parcel. A local geotechnical report, typically $1,000-$5,000 (around $2,700 typical), is the only way to know what one lot in McHenry County will actually do.

McHenry County: the real numbers

McHenry 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.

How McHenry County, IL compares

Among the 3,085 rated counties on this site, McHenry County, IL ranks 1,074 most-constrained nationally, and 83 of 101 within Illinois. McHenry County, IL is 603 square miles with a population of 315,959.

For contrast

Orleans Parish, LA carries this site's most-constrained reading. Kent County, TX and Union County, OH 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 Macon County, IL and Tazewell County, IL. The full underlying dataset is downloadable directly, one row per county.