Off-Grid Living in Sumner County, Tennessee

Sumner County is one of the exceptions to the "rural Tennessee has no zoning" rule I usually see. The unincorporated parts of the county (outside Gallatin, Hendersonville, Portland, White House, and Goodlettsville, which each run their own separate departments) are covered by the Sumner County Zoning Resolution, and the Planning and Engineering Department reviews all new construction for compliance before anything gets built. That's a real difference from counties where you can just build on raw land with no zoning check at all, so the first thing I'd do here is confirm your parcel's zoning district before assuming any use is by-right. The county is also actively amending its code, including a new Rural Preservation district, so what applied to a neighboring parcel a year or two ago may not apply to yours today.

Building permits are required and enforced by the Sumner County Building & Codes Department, not something you can skip. They charge more if work starts without a permit, and a permit becomes invalid if work doesn't start within a set window (the county's own page has that detail, so check current numbers with them rather than trust anything I say about the specifics). To get a permit, you need septic approval (a valid permit or an affidavit of disclosure) and either a water tap receipt or a well driller's report before you can get a Certificate of Occupancy. Tiny homes have a dedicated inspection track through the county, though it's not confirmed whether they've formally adopted the IRC's Appendix Q. Living full-time in an RV on raw land isn't confirmed as a permitted path since the county's permit process is built around conventional septic/water hookups.

Septic is handled entirely at the state level, not by the county. You apply through TDEC's online portal, a TDEC Environmental Scientist evaluates the site, and after a licensed installer finishes the work, TDEC issues a Certificate of Completion. I found no dry-cabin or composting-toilet exemption specific to Sumner County, so the state baseline applies, meaning composting toilets generally need NSF Standard 41 certification.

Wells are also a state matter under the Tennessee Water Well Act: your driller must be licensed, and a Notice of Intent goes to the state director before drilling starts. The county doesn't add its own separate well permit, it just wants proof (the driller's report) as part of your building permit file. Water testing isn't mandated by the state, just recommended.

Rainwater collection looks fine since no county restriction turned up in my research; greywater reuse is genuinely unclear at the county level, so that's a call to make directly to Building & Codes. Disconnecting from grid electricity is unregulated, but you can't skip septic/sewer and water solutions if you're going through the county's building permit process for a habitable structure.