New Hanover County, NC Environmental Rules: Flood Elevation Requirements (2026)

Sec. 29-64 sets specific construction standards wherever base flood elevation data has been provided. Subsection (1) requires new construction or substantial improvement of a residential structure to have its lowest floor, including any basement, elevated to or above base flood elevation, with no floodproofing alternative allowed for homes. Subsection (2) gives commercial, industrial and other nonresidential structures a choice: elevate the lowest floor the same way, or floodproof the structure and its utility and sanitary facilities watertight below base flood level, with walls able to resist hydrostatic and hydrodynamic loads, certified by a registered professional engineer or architect under Sec.

29-67(3). In coastal high-hazard, or V-zone, areas, subsection (5) raises the bar further: buildings must sit landward of the mean high tide, with the lowest supporting member no lower than base flood elevation and all space below it open, except for breakaway walls, to avoid impeding floodwater; the pilings or columns must be anchored to withstand the base flood's forces, all certified by a professional engineer, architect, or, for the elevation figure alone, a registered land surveyor. Mobile and manufactured homes get their own rule in subsection (3): the stand or lot must be elevated on compacted fill or pilings so the home's lowest floor sits at or above base flood level, with anchoring components able to carry 4,800 pounds of force.

The building inspector records the actual elevation achieved for every new or substantially improved structure under Sec. 29-40(5), and where no elevation data exists yet, must reasonably use whatever federal, state or other data is available under Sec. 29-40(12).