In all special flood hazard areas where base flood elevations have been provided in the Flood Insurance Study or generated according § 154.28(A), the following provisions shall apply:
(A) Residential construction. New construction or substantial improvement of any residential structure (including manufactured homes) shall have the lowest floor, including basement, elevated no lower than the base flood elevation.
(B) Non-residential construction. New construction or substantial improvement of any commercial, industrial, or non-residential building (or manufactured home) shall have the lowest floor, including basement, elevated to no lower than the base flood elevation. Buildings located in all A and AE zones may be flood-proofed in lieu of being elevated provided that all areas of the building components below the elevation corresponding to the BFE plus 1 foot are water tight with walls substantially impermeable to the passage of water, and use 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 division are satisfied.
(C) Elevated buildings. Enclosed areas, of new construction or substantially improved structures, which are below the regulatory flood protection elevation shall:
(1) Not be designed or used for human habitation, but shall only be used for parking of vehicles, building access, or limited storage of maintenance equipment used in connection with the premises. Access to the enclosed area shall be the minimum necessary to allow for parking of vehicles (garage door) or limited storage of maintenance equipment (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;
(2) Be constructed entirely of flood resistant materials below the regulatory flood protection elevation;
(3) In the Coastal High Hazard District, follow the standards for elevation outlined in this chapter.
(4) Include, in Zones A, AE, and A1-30, measures 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 the following minimum design criteria:
(a) Provide a minimum of 2 openings on different sides of each enclosed area subject to flooding.
(b) The total net area of all openings must be at least 1 square inch for each square foot of enclosed area subject to flooding.
(c) If a building has more than 1 enclosed area, each area must have openings to allow floodwaters to automatically enter and exit.
(d) The bottom of all required openings shall be no higher than 1 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 floodwaters in both directions.
(f) Foundation enclosures made of flexible skirting are not considered enclosures for regulatory purposes, and, therefore, do not require openings. Masonry or wood underpinning, regardless of structural status, is considered an enclosure and requires openings as outlined above.
(D) Standards for manufactured homes and recreational vehicles.
(1) All manufactured homes placed, or substantially improved, on individual lots or parcels, in expansions to existing manufactured home parks or subdivisions, in a new manufactured home park or subdivision or in an existing manufactured home park or subdivision on which a manufactured home has incurred substantial damage as the result of a flood, must meet all the requirements for new construction, including the elevation and anchoring requirements in § 154.26(A) and (B), and division (A) of this section.
(2) All manufactured homes placed or substantially improved in an existing manufactured home park or subdivision in which a manufactured home has not incurred substantial damage as the result of a flood shall be elevated so that either:
(a) The lowest floor of the manufactured home is elevated no lower than the base flood elevation; or
(b) The manufactured home chassis is supported by reinforced piers or other foundation elements of at least equivalent strength that are no less than 36 inches in height above grade; and
(c) Be securely anchored to the adequately anchored foundation system to resist flotation, collapse and lateral movement.
(3) All recreational vehicles placed on sites must either:
(a) Be on the site for fewer than 180 consecutive days;
(b) 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 security devices and has no permanently attached additions); or
(c) Meet all the requirements for manufactured homes in division (D) of this section.
(Ord. passed 8-12-2008)