Jonesborough has been here since 1779. The dirt under it still outgasses.

Jonesborough was founded in 1779. It is the oldest town in Tennessee, the Washington County seat, and a National Register historic district people drive to on weekends. It is also a Zone 1 county seat with dirt crawls, fieldstone, and brick that predates every radon standard written in this country.

Jonesborough's housing is the point. Historic stone, brick, and dirt crawls are not the same job as a Boones Creek slab.

Historic fabric versus a Boones Creek slab

Main Street and the historic grid are limestone foundations, brick, log, and later wood frame. A lot of those crawls are dirt, low, and interrupted by chimneys and stone piers. A polyethylene membrane still works. It takes more detailing than a 2005 ranch with a clean stem wall.

You cannot vent a historic crawl with "a little more airflow" and call it mitigation. You also cannot core a fieldstone wall the way you core a poured footer without looking first. We design on site. If a preservation rule or a town permit is in play, we talk about discharge path and fan placement before we drill a pretty hole in a street-facing brick pier.

Outside the historic core, Jonesborough has county-seat ranches, newer streets toward 11E, and houses that feel like rural Washington County. Those are closer to the Johnson City crawl story. Say which one you have.

Why 1779 matters and why it doesn't

Age tells you about pathways: more joints, more stone, more dirt, more "we never sealed the chase around the stack." Age does not tell you the pCi/L. A tight remodel inside an 1840 brick can hold radon. A leaky hall-and-parlor can dilute it. The test is still the test.

Tourism does not change soil gas. A short-term rental on the historic walking tour still needs a lowest-level measurement if someone sleeps there. If you're buying a B&B, treat it like a real-estate test with extra rooms.

County seat practicalities

Deeds, inspections, and well questions all run through this town even when the house is in Limestone or Telford. Those rural addresses are more likely to be on a well. Northern Washington County's spring-water radon hotspot is a research finding, not a Jonesborough tap score. Air first. Water if you want the lab.

We also cover Johnson City, Kingsport, and Bristol TN. Request a quote with "historic district" or "out toward 11E" so we bring the right expectations about the crawl.