Franklin County, ID Shrink-Swell Risk

Franklin County, ID's soil, for shrink-swell risk

Moderate

Franklin County, ID: USDA's soil survey rates 46.4% of the county "Moderate" for shrink-swell potential (3.49% linear extensibility). A real but modest amount of movement - standard foundations usually hold up, but drainage and moisture control around the foundation still matter more than on low-risk soil.

What Franklin County's reading doesn't cover

Two lots a mile apart in Franklin 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 Franklin County, ID rating "Moderate", 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 Franklin County, ID compares

Nationally, Franklin County, ID is the 851-most-constrained of 3,085 rated counties for shrink-swell soil. Within Idaho alone it ranks 2 of 44. Franklin County, ID is 663 square miles with a population of 15,638.

For contrast

Orleans Parish, LA carries this site's most-constrained reading. Carlton County, MN and Marin County, CA 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 Idaho

Every county in Idaho is on this site, including Idaho County, ID and Custer County, ID. The full underlying dataset is downloadable directly, one row per county.