Rockingham County, NH Shrink-Swell Risk

Shrink-swell potential in Rockingham County, NH

Low

Soil across 94.2% of Rockingham County, NH comes back "Low" in USDA's shrink-swell data, averaging 0.79% linear extensibility. Among the 3,144 counties on this site, that's the clean result: little shrink-swell movement, standard construction the likely outcome.

What this number does and doesn't tell you

This is a countywide, area-weighted figure across every soil survey map unit in Rockingham County, NH - 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 Rockingham County.

Rockingham County: the real numbers

Rockingham 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, Rockingham County, NH ranks 2,993 most-constrained nationally, and 9 of 10 within New Hampshire. The county spans 696 square miles, home to 322,433 people.

Before you act on this

Orleans Parish, LA carries this site's most-constrained reading. Lafayette County, MS and Louisa County, IA 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 New Hampshire

Every county in New Hampshire is on this site, including Strafford County, NH and Grafton County, NH. The full underlying dataset is downloadable directly, one row per county.