Grayson County, VA Shrink-Swell Risk
Grayson County, VA's soil, for shrink-swell risk
Low
Grayson County, VA: USDA's soil survey rates 97.7% of the county "Low" for shrink-swell potential (1.53% linear extensibility). 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.
What Grayson County's reading doesn't cover
Two lots a mile apart in Grayson County can carry different soil, even though they share one countywide reading. The real answer for one lot is still a site-specific geotechnical report, running about $1,000-$5,000 (typically near $2,700).
What it costs to find out, versus to ignore it
With Grayson 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.
How Grayson County, VA compares
Nationally, Grayson County, VA is the 2,464-most-constrained of 3,085 rated counties for shrink-swell soil. Within Virginia alone it ranks 109 of 114. Grayson County covers 442 square miles and counts 15,265 residents.
For contrast
Orleans Parish, LA carries this site's most-constrained reading. Washington County, UT and Haskell 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 Virginia
Every county in Virginia is on this site, including Warren County, VA and Poquoson city, VA. The full underlying dataset is downloadable directly, one row per county.