Kingsport, TN Environmental Rules: Flood Elevation Requirements (2026)

Section 114-268 sets the elevation standards for the City of Kingsport, Tennessee, in Division 5 of Chapter 114, and the city building official administers them. In AE zones with published base flood elevation data, a new or substantially improved residential building or manufactured home needs its lowest floor, basement included, elevated to no lower than one foot above the base flood elevation. The division defines freeboard as a factor of safety expressed in feet above a flood level, and the AO rule in § 114-272 labels its one-foot margin a freeboard.

Where the FIRM shows an approximate A zone with no base flood elevation and no alternative data, the administrator requires the lowest floor at least three feet above the highest adjacent grade. Non-residential buildings follow the same two numbers, but the owner can floodproof rather than elevate. A floodproofed building must be watertight below the required level, with walls substantially impermeable to water and structural components able to resist hydrostatic and hydrodynamic loads and buoyancy. A Tennessee registered professional engineer or architect must certify the design and give the certification to the administrator.

Shallow flooding zones carry their own numbers. In an AO zone the lowest floor must reach at least the depth number printed on the FIRM plus a freeboard of one foot above the highest adjacent grade, or at least three feet above the highest adjacent grade when the map shows no depth number (§ 114-272). Manufactured homes in an existing park in AE zones sit on a permanent foundation no lower than one foot above base flood elevation. In approximate A zones the chassis rides on reinforced piers at least three feet high above the highest adjacent grade.

Enclosures below the lowest floor are limited to parking, storage and building access. They need a minimum of two openings with a total net area of not less than one square inch for every square foot of enclosed area, and the bottom of every opening sits no higher than one foot above finished grade. When a building sits in more than one flood zone, or in a zone with several base flood elevations, the whole structure meets the standards for the most hazardous zone and the highest base flood elevation (§ 114-267).