Smyth County, VA Shrink-Swell Risk

What Smyth County, VA's soil means for a foundation

Low

USDA's SSURGO data puts Smyth County, VA's soil at "Low" shrink-swell potential, an area-weighted linear extensibility of 2.79% across 63.5% 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 Smyth County, VA at once, not any single address. 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 Smyth County.

Report cost vs. repair cost

With Smyth County, VA 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, Smyth County, VA is the 1,349-most-constrained of 3,085 rated counties for shrink-swell soil. Within Virginia alone it ranks 24 of 114. Smyth County, VA is 451 square miles with a population of 29,137.

For contrast

Orleans Parish, LA carries this site's most-constrained reading. Lorain County, OH and Gloucester County, NJ 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 Virginia

Every county in Virginia is on this site, including Dickenson County, VA and Covington city, VA. The full underlying dataset is downloadable directly, one row per county.