Building permits, zoning and land rules in Union County, Tennessee

Yes. Union County requires building permits, and the Assessor of Property says every county building permit must be purchased in that office¹. The office sells permits for new construction, assigns 911 addresses for new construction, and does not offer its building permits online¹.

The available information does not establish which locally adopted building code applies, what inspections follow, or whether a certificate of occupancy is required. Ask the Assessor of Property to identify the current code official, required inspections, permit fee and closeout documents for the exact project before work begins. Tennessee's Fire Marshal lists Union County as exempt from the State Residential Building Program, which means the state does not run residential permitting here; that listing does not establish whether Union County has a local building code or what it requires^5,9.

The Union County Assessor of Property is the practical first stop for a house or other new construction because the office sells the county's building permits and assigns new-construction 911 addresses¹. Visit the Assessor of Property at 901 Main Street, Suite 106, Maynardville, or call the published office number before making the trip¹. Permits are not offered online¹.

Ask the office what plans and site documents to bring, how the fee is calculated, which inspections apply, and who reviews zoning. Union County's published information confirms the permit-sales role, but we could not confirm a separate county building department, inspection schedule or current fee schedule. The distinction matters because Tennessee's state residential program does not replace local zoning, septic, floodplain, grading or electrical approvals⁹.

Union County has adopted zoning and subdivision regulations, so rural land should not be treated as unrestricted². Tennessee law allows counties to zone land outside municipal corporations, while incorporated places may administer their own rules¹⁰. Union County maintains a Planning & Zoning Coordinator, so that is the office to ask about the parcel². Dividing a tract into two or more lots where a septic system will be used also triggers a state subdivision evaluation by TDEC, unless every resulting parcel is 5 acres or larger¹¹. Before relying on a listing or a seller's description, ask Union County which jurisdiction and zoning district cover the parcel and whether the proposed dwelling, accessory building or business use is allowed.

We could not confirm a current official district schedule for setbacks, minimum dwelling size, minimum lot size, lot coverage or building height. Ask for a written zoning determination tied to the parcel, particularly for a tiny home, manufactured home, accessory dwelling or long-term RV use. A qualifying agricultural structure may receive protection from county zoning only when it is on land devoted to agricultural use and incidental to the agricultural enterprise, subject to stated location and floodplain exceptions¹².

TDEC administers septic permitting for Union County through the Knoxville Environmental Field Office⁴. Union County is not among the contract counties that may require an additional local septic permit, and a septic permit applies to a new system, a modification or a repair^6,13. Obtain that approval before dirt work or construction begins, including preparation of a building pad¹¹.

TDEC evaluates the site and may request a site plan, soil map or engineered design; processing can take up to 45 days after a complete application arrives⁶. The installer must arrange the final inspection before covering the system, and TDEC issues a Certificate of Completion after approval⁶. Only about 11.4% of Union County soils lack severe limits for a conventional drain field, so make septic feasibility an early purchase contingency rather than assuming a conventional layout will work⁸. Electrical-service processing also requires written notice of public sewer service, a septic application or use of an existing system¹¹.

We could not confirm a Union County rule that allows or prohibits living in an RV on private land, temporary camping, tiny-home occupancy, manufactured-home occupancy or accessory dwellings. Because Union County has zoning, a small structure or vehicle is not automatically approved as a residence merely because the land is rural². Ask the county for a parcel-specific answer covering the proposed use, duration, utility connections, setbacks and any required occupancy approval.

A tiny home used as a dwelling still needs a workable sanitation path: installation of a septic system or repair of a faulty system requires a TDEC construction permit⁶. For an owner-built residence, Tennessee allows a homeowner to build a home as their own residence, but it cannot be sold or leased, and the homeowner cannot have been issued a homeowner building permit in the prior 24 months⁷. That contractor-licensing exception does not itself settle zoning, building-code, septic or RV-occupancy questions.

1. Ask Union County to confirm the parcel's jurisdiction, zoning district, allowed dwelling type and dimensional standards; the county has zoning, but the current parcel-level standards were not confirmed².
2. Establish septic feasibility and apply through TDEC before grading or preparing the building pad; a septic construction permit is required for a new system or repair¹¹.
3. Obtain the 911 address and purchase the Union County building permit in person from the Assessor of Property¹.
4. Ask which locally required inspections and electrical approvals apply; electrical-service processing requires sewer or septic documentation¹¹.
5. If the driveway connects to a Tennessee state highway right-of-way, obtain the required TDOT highway entrance permit before constructing or changing it¹⁴.
6. Have the septic installer schedule TDEC's final inspection before covering the system and retain the Certificate of Completion after approval⁶.

Start with buildability, not the asking price. Only about 21.9% of Union County land is at a slope of 15% or less, and about 70.2% is wooded, so verify the actual homesite, access grade and clearing needs on the parcel⁸. Septic deserves equal attention because only about 11.4% of soils lack severe limitations for a conventional drain field⁸.

Confirm the zoning district, setbacks and permitted dwelling type with the county because Union County has zoning but the current district details were not confirmed². Check whether the site lies in a flood hazard area and ask the county who handles development approval there. A driveway on state highway right-of-way requires TDOT approval, while a county-road entrance should be discussed with the county before construction¹⁴. For budgeting context, the effective property-tax rate is about 0.4%, and the median annual property-tax bill is about $720⁸.