Structures in CAZs shall be designed and constructed to meet V Zone requirements, including requirements for breakaway walls. However, the NFIP regulations also require flood openings in walls surrounding enclosures below
in CAZs (see Technical Bulletin 1, Openings in Foundation Walls and Walls of Enclosures). Breakaway walls used in CAZs must have flood openings that allow for the automatic entry and exit of floodwaters to minimize damage caused by hydrostatic loads. Openings also function during smaller storms or if anticipated wave loading does not occur with the base flood.
(A) All new construction and substantial improvements shall be elevated so that the bottom of the lowest horizontal structural member of the lowest floor (excluding pilings or columns) is no lower than the regulatory flood protection elevation. Floodproofing shall not be utilized on any structures in
s to satisfy the regulatory flood protection elevation requirements.
(B) All new construction and substantial improvements shall have the space below the bottom of the lowest horizontal structural member of the lowest floor either be free of obstruction or constructed with breakaway walls, open wood latticework or insect screening, provided they are not part of the structural support of the building and are designed so as to breakaway, under abnormally high tides or wave action without causing damage to the elevated portion of the building or supporting foundation system or otherwise jeopardizing the structural integrity of the building. The following design specifications shall be met:
(1) Material shall consist of open wood or plastic lattice having at least 40% of its area open;
(2) Insect screening; or
(3) Breakaway walls shall meet the following design specifications:
(a) Breakaway walls shall have flood openings to automatically equalize hydrostatic flood forces on walls by allowing for the entry and exit of floodwaters. To meet this requirement, the openings must either be certified by a professional engineer or architect or meet or exceed the design criteria in § 152.441; and
(b) Design safe loading resistance shall be not less than ten nor more than 20 pounds per square foot; or
(c) Breakaway walls that exceed a design safe loading resistance of 20 pounds per square foot (either by design or when so required by state or local codes) shall be certified by a registered professional engineer or architect that the breakaway wall will collapse from a water load less than that which would occur during the base flood event, and the elevated portion of the building and supporting foundation system shall not be subject to collapse, displacement, or other structural damage due to the effects of wind and water loads acting simultaneously on all building components (structural and non-structural). The water loading values used shall be those associated with the base flood. The wind loading values used shall be those required by the North Carolina State Building Code.
(C) Concrete pads, including patios, decks, parking pads, walkways, driveways, etc. must meet the provisions of § 152.445(E).
(D) All new construction and substantial improvements shall meet the provisions of § 152.445(C).
(E) A registered professional engineer or architect shall certify that the design, specifications and plans for construction are in compliance with the provisions of § 152.426 and § 152.445, on the current version of the North Carolina V- Zone Certification form or a locally developed V-Zone Certification form.
(F) Recreational vehicles may be permitted in
s provided that they meet the recreational vehicle criteria of § 152.441.
(G) Fill/grading must meet the provisions of § 152.445(J).
(H) Decks and patios must meet the provisions of § 152.445(N) and (O).
(I) In
,
other than buildings and structures must meet the provisions of § 152.445(P).
(Ord. 2020-O3, passed 6-8-2020)