Accessory structures including detached garages.

The following standards apply to new and substantially improved accessory structures, including detached garages, in the areas of special flood hazard shown on the Flood Insurance Rate Map designated in § 170-6.

A. The accessory structure must meet the definition of structure, for floodplain management purposes, provided in 44 CFR 59.1, where walled and roofed shall be interpreted as having two outside rigid walls and a fully secured roof.

B. The accessory structure should be small, as defined by the community and approved by FEMA, and represent a minimal investment. Accessory structures of any size may be considered for a variance; however, FEMA considers accessory structures that meet the following criteria to be small and therefore not necessarily in need of a variance, if the community chooses to allow it:

(1) Located in an A Zone (A, AE, A1-A30, AR, A99) and less than or equal to the size of a one-story, two-car garage.

(2) Located in a V Zone (V, VE, V1-V30) and less than or equal to 100 square feet.

C. Accessory structures must meet the standards of § 170-16A, Anchoring.

D. The portions of the accessory structure located below BFE plus two feet of freeboard must be constructed with flood-resistant materials.

E. Mechanical and utility equipment for the accessory structure must be elevated or dry floodproofed to or above BFE plus two feet of freeboard.

F. Within Zone AO and Zone A, if base flood elevation data are not available, areas below three feet above the highest adjacent grade shall be constructed using methods and practices that minimize flood damage.

G. The accessory structure must comply with the floodway encroachment provisions of the NFIP.

H. The accessory structure must be wet floodproofed to protect the structure from hydrostatic pressure. The design must meet the NFIP design and performance standards for openings per 44 CFR 60.3(c)(5) and must allow for the automatic entry and exit of floodwaters without manual operation or the presence of a person (or persons)

I. Within Zone V1-V30, VE, V, and Coastal A, unelevated accessory buildings must be unfinished inside, constructed with flood-resistant materials, and used only for storage. When an accessory building is placed in these zones, the design professional must determine the effect that debris from the accessory building will have on nearby buildings. If the accessory building is large enough that its failure could create damaging debris or divert flood flows, it must be elevated above the base flood elevation plus two feet.