Sevier County, TN Accessory Structures: ADU Rules (2026)

Sevier County's Zoning Resolution (last amended 12-15-2025) does not define 'accessory dwelling unit,' 'guest house,' or 'in-law suite,' but Section 406 grants property owners the right to build a second principal dwelling: 'Two (2) single family dwellings or one (2) duplex and its customary accessory buildings may be hereafter be erected on any lot of record, unless otherwise restricted by these regulations.' This applies in the A-1 Agricultural District (502.2.1), R-1 Rural Residential District (503.2.1), R-2M Medium Density Residential District (504.2.1, which inherits R-1 uses), and R-2 High Density Residential District (505.2.1, which inherits R-1 and R-2M uses). Each dwelling must independently satisfy the lot-size minimums in Section 602.1 (A-1: 30,000 sf; R-1: 30,000 sf, or 25,000 sf with public water; R-2M: 15,000 sf; R-2: 7,500 sf) and the setback rules in Section 601 (front 20 ft on residential/cul-de-sac roads, side and rear 10 ft in A-1/R-1/R-2M/R-2, or 25 ft on Critical Slope/Industrial). Each dwelling unit must provide complete, independent living facilities including permanent provisions for living, sleeping, eating, cooking, and sanitation per the Section 300 'Dwelling Unit' definition. The 'Accessory Building or Use' definition in Section 300 limits accessory structures to uses subordinate to the principal building, and the floodplain Article XI specifies accessory structures are for 'parking of vehicles and storage' only - not as dwellings. Sevier County operates under Tennessee Code Annotated Title 13 (Local Planning) authority; statewide, T.C.A. §13-7-101 grants counties zoning power but Tennessee has no statewide ADU mandate. The cities of Gatlinburg, Pigeon Forge, and Sevierville have their own zoning codes and are not covered by this county resolution. Building permits are issued by the Sevier County Planning & Zoning Department at 227 Cedar St, Sevierville (865-453-3882); a site plan and septic/health-department approval are required where public sewer is unavailable.