Union County, TN Shrink-Swell Risk
Union County's SSURGO shrink-swell reading
Low
In Union County, TN, 64.7% of the surveyed soil carries a "Low" shrink-swell rating, 2.17% linear extensibility on average. 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.
Before you rely on this for one address
Union County's reading is an average across the whole county, not a promise about any one lot inside it. The real answer for one lot is still a site-specific geotechnical report, running about $1,000-$5,000 (typically near $2,700).
Budgeting for Union County, TN
Union 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 Union County, TN compares
Among the 3,085 rated counties on this site, Union County, TN ranks 1,828 most-constrained nationally, and 42 of 95 within Tennessee. Union County, TN is 224 square miles with a population of 21,064.
For contrast
Orleans Parish, LA carries this site's most-constrained reading. Kennebec County, ME and Adams County, IN 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 Tennessee
Every county in Tennessee is on this site, including Giles County, TN and Cocke County, TN. The full underlying dataset is downloadable directly, one row per county.