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Any combination of structural and non-structural additions, changes, or adjustments to structures which reduce or eliminate flood damage to real estate or improved real property, water and sanitary facilities, structures and their contents.

The National Flood Insurance Program (NFIP) allows a new or substantially improved non-residential building in an A Zone (Zone A, AE, A1-30, AR, AO or AH) to have a lowest floor below the Base Flood Elevation (BFE), provided that the design and methods of construction have been certified by a registered professional engineer or architect as being dry floodproofed in accordance with established criteria.

Floodproofing of areas below the BFE in residential buildings is not permitted under the NFIP exception communities that have been granted an exception to permit floodproofed basements. Floodproofing is not permitted in Coastal High Hazard Areas (Zone V, VE, or V1-30). It is recommended that floodproofing be implemented up to one foot above BFE for a factor of safety and to receive full credit for flood insurance rating.

Limited enclosed areas below elevated within newly constructed and substantially improved residential and non-residential structures may be permitted provide that they are wet floodproofing. See Enclosure. Certain other categories of structures may be allowed to be wet floodproofed if a variance is issued and other requirements are met. See Agricultural Building and Accessory Building.

National Flood Insurance Program Requirements

  • 59.1 - Definition
  • 60.0 - Criteria for Land Management and Use
  • 60.3 (c)(3) - Requirements for Nonresidential Buildings
  • 60.3 (c)(4) - Floodproofing Certification
  • 60.3 (c)(8) - Zone AO Subdivision Requirements
Last updated July 8, 2020