Portsmouth, VA Environmental Rules: Flood Elevation Requirements (2026)

1-11(d)(1). The lowest floor, including the basement and any HVAC or duct work, must sit at or above that DFE, and unlike commercial buildings, homes cannot substitute flood-proofing for elevation below the DFE; the section states flatly that no floodproofing below the design flood elevation of residential construction is allowed. 1-11(d)(2): they may be elevated to the same BFE-plus-three standard or flood-proofed watertight to that level instead, but a Virginia-registered professional engineer or architect must certify the design and the floodplain administrator keeps that certification on file.

Coastal properties face an even stricter version of the same three-foot buffer: buildings in the VE or V zones (coastal high hazard areas) and the Coastal A zone must have the lowest horizontal structural member elevated at least three feet above base flood level on pilings or columns, anchored to resist wind and water loads acting simultaneously. 1-11(f)(4)).