Martin County, NC Shrink-Swell Risk

What Martin County, NC's soil means for a foundation

Low

USDA's SSURGO data puts Martin County, NC's soil at "Low" shrink-swell potential, an area-weighted linear extensibility of 2.07% across 74% of the county's surveyed land. That's as favorable a county-level reading as this dataset produces - standard foundation practice, pending one lot's own geotechnical report.

This is a county figure, not a lot figure

USDA's survey covers the whole of Martin County, NC at once, not any single address. The real answer for one lot is still a site-specific geotechnical report, running about $1,000-$5,000 (typically near $2,700).

Report cost vs. repair cost

With Martin County, NC 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, Martin County, NC is the 1,914-most-constrained of 3,085 rated counties for shrink-swell soil. Within North Carolina alone it ranks 34 of 100. Martin County covers 456 square miles and counts 21,523 residents.

See how another county compares

Orleans Parish, LA carries this site's most-constrained reading. Webster County, KY and Santa Rosa County, FL 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 North Carolina

Every county in North Carolina is on this site, including Caldwell County, NC and Wayne County, NC. The full underlying dataset is downloadable directly, one row per county.