(A) Residential construction. New construction or substantial improvement of any residential structure (including manufactured homes) shall have the reference level, including basement, elevated no lower than the regulatory flood protection elevation.
(B) Non-residential construction. New construction or substantial improvement of any commercial, industrial, or other non-residential structure shall have the reference level, including basement, elevated no lower than the regulatory flood protection elevation. Structures located in A, AO, AE and A1-30 zones may be flood-proofed to the regulatory flood protection elevation in lieu of elevation provided that all areas of the structure below the required flood protection elevation are water-tight with walls substantially impermeable to the passage of water, using structural components having the capability of resisting hydrostatic and hydrodynamic loads and the effect of buoyancy. A registered professional engineer or architect shall certify that the standards of this section are satisfied. Such certification shall be provided to the official as set forth in § 153.26(C).
(C) Manufactured homes.
(1) New or replacement manufactured homes shall be elevated so that the reference level of the manufactured home is no lower than the regulatory flood protection elevation.
(2) Manufactured homes shall be securely anchored to an adequately anchored foundation to resist flotation, collapse, and lateral movement in accordance with the State of North Carolina Regulations for Manufactured/Mobile Homes, 1995 Edition, and any revision thereto adopted by the Commissioner of Insurance pursuant to G.S. § 143-143.15 or a certified engineered foundation. Additionally, when the elevation would be met by an elevation of the chassis 36 inches or less above the grade at the site, the chassis shall be supported by reinforced piers or other foundation elements of at least equivalent strength. When the elevation of the chassis is above 36 inches in height, an engineering certification is required.
(3) All foundation enclosures or skirting shall be in accordance with division (D) below.
(4) An evacuation plan must be developed for evacuation of all residents of all new, substantially improved, or substantially damaged manufactured home parks or subdivisions located within flood-prone areas. This plan shall be filed with and approved by the Floodplain Administrator and the local Emergency Management Coordinator.
(D) Elevated buildings. New construction or substantial improvements of elevated buildings that include fully enclosed areas that are below the regulatory flood protection elevation shall not be designed to be used for human habitation, but shall be designed to be used only for parking of vehicles, building access, or limited storage of maintenance equipment used in connection with the premises, be constructed entirely of flood resistant materials below the regulatory flood protection level in A, AO, AE, and A1-30 Zones and meet the following design criteria:
(1) Measures for complying with this requirement shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of flood waters. To meet this requirement, the foundation must either be certified by a professional engineer or architect or meet the following minimum design criteria:
(a) Provide a minimum of two openings on different sides of each enclosed area subject to flooding;
(b) The total net area of all openings must be at least one square inch for each square foot of each enclosed area subject to flooding;
(c) If a building has more than one enclosed area, each area must have openings on exterior walls to allow flood water to directly enter;
(d) The bottom of all required openings shall be no higher than one foot above the adjacent grade;
(e) Openings may be equipped with screens, louvers, or other opening coverings or devices provided they permit the automatic flow of flood waters in both directions; and
(f) Foundation enclosures:
1. Vinyl or sheet metal skirting is not considered an enclosure for regulatory and flood insurance rating purposes. Therefore such skirting does not require hydrostatic openings as outlined above; and
2. Masonry or wood underpinning, regardless of structural status, is considered an enclosure and requires hydrostatic openings as outlined above to comply with this chapter.
(2) Access to the enclosed area shall be the minimum necessary to allow for parking of vehicles (garage door) or limited storage of maintenance equipment used in connection with the premises (standard exterior door) or entry to the living area (stairway or elevator). The interior portion of such enclosed area shall not be partitioned or finished into separate rooms, except to enclose storage areas.
(E) Additions/improvements.
(1) Additions and/or improvements to pre-FIRM structures whereas the addition and/or improvements in combination with any interior modifications to the existing structure:
(a) Are not a substantial improvement, the addition and/or improvements must be designed to minimize flood damages and must not be any more non-conforming than the existing structure; and
(b) Are a substantial improvement, both the existing structure and the addition and/or improvements must comply with the standards for new construction.
(2) Additions to post-FIRM structures with no modifications to the existing structure shall require only the addition to comply with the standards for new construction.
(3) Additions and/or improvements to post-FIRM structures whereas the addition and/or improvements in combination with any interior modifications to the existing structure:
(a) Are not a substantial improvement, the addition and/or improvements only must comply with the standards for new construction; and
(b) Are a substantial improvement, both the existing structure and the addition and/or improvements must comply with the standards for new construction.
(4) Where a fire wall or independent perimeter load-bearing wall is provided between the addition and the existing building, the addition(s) shall be considered a separate building and only the addition must comply with the standards for new construction.
(F) Recreational vehicles. Recreation vehicles placed on sites within a special flood hazard area shall either:
(1) Be on-site for fewer than 180 consecutive days and be fully licensed and ready for highway use (a recreational vehicle is ready for highway use if it is on its wheels or jacking system, is attached to the site only by quick disconnect type utilities and has no permanently attached additions); or
(G) Temporary structures. Prior to the issuance of a Floodplain Development Permit for a temporary structure, the following requirements must be met:
(1) Applicants must submit to the Floodplain Administrator a plan for the removal of such structure(s) in the event of a hurricane or flash flood warning notification. The plan must include the following information:
(a) A specified time period for which the temporary use will be permitted;
(b) The name, address, and phone number of the individual responsible for the removal of the temporary structure;
(c) The time frame prior to the event at which a structure will be removed (i.e. minimum of 72 hours before landfall of a hurricane or immediately upon flood warning notification);
(d) A copy of the contract or other suitable instrument with a trucking company to insure the availability of removal equipment when needed; and
(e) Designation, accompanied by documentation, of a location outside the special flood hazard area to which the temporary structure will be moved.
(2) The above information shall be submitted in writing to the Floodplain Administrator for review and written approval.
(H) Accessory structures. When accessory structures (sheds, detached garages, and the like) are to be placed within a special flood hazard area, the following criteria shall be met:
(1) Accessory structures shall not be used for human habitation (including work, sleeping, living, cooking, or restroom areas);
(2) Accessory structures shall be designed to have low flood damage potential;
(3) Accessory structures shall be constructed and placed on the building site so as to offer the minimum resistance to the flow of floodwaters;
(4) Accessory structures shall be firmly anchored in accordance with § 153.45(A);
(5) All service facilities such as electrical and heating equipment shall be installed in accordance with § 153.45(D);
(6) Openings to relieve hydrostatic pressure during a flood shall be provided below regulatory flood protection elevation in conformance with division (D)(1) above; and
(7) An accessory structure with a footprint less than 150 square feet does not require an elevation or flood-proofing certificate. Elevation or flood-proofing certifications are required for all other accessory structures in accordance with § 153.26(C).
(Ord. passed 12-1-03)