A. Residential structures.
(1) Within the Zone AE Without Floodway Subdistrict, any new construction or substantial improvement shall have the lowest floor (including basement) elevated to at least 1 1/2 feet above the Base Flood Elevation (BFE).
(2) Within the Zone A Subdistrict, where there are no Base Flood Elevations specified on the FIRM, any new construction or substantial improvement shall have the lowest floor (including basement) elevated to least 1 1/2 feet above the BFE, determined in accordance with § 600-1818C of this Part.
(3) Within Shallow Flooding Subdistrict (if applicable), any new construction or substantial improvement shall have the lowest floor (including basement) at or above the highest adjacent grade at least as high as the flood depth number specified on the FIRM.
(4) The design and construction standards and specifications contained in Chapter 180, Construction Codes, Chapter 295, Historic Districts, and Chapter 302, House Numbering, shall be utilized.
B. Nonresidential structures.
(1) Within the Zone AE Without Floodway Subdistrict, any new construction or substantial improvement of a nonresidential structure shall have the lowest floor (including basement) elevated to least 1 1/2 feet above the BFE.
(2) In the Zone A Subdistrict, where no Base Flood Elevations are specified on the FIRM, any new construction or substantial improvement shall have the lowest floor (including basement) elevated or completely floodproofed to least 1 1/2 feet above the BFE, determined in accordance with section § 600-1818C of this Part.
(3) In Zone AO (if applicable), any new construction or substantial improvement shall have their lowest floor elevated or completely floodproofed above the highest adjacent grade to at least as high as the flood depth number specified on the FIRM.
(4) Any nonresidential structure, or part thereof, made watertight below the BFE shall be floodproofed in accordance with the WI or W2 space classification standards contained in the publication entitled "Flood-Proofing Regulations" published by the U.S. Army Corps of Engineers (June 1972, as amended March 1992) or with some other equivalent standard. All plans and specifications for such floodproofing shall be accompanied by a statement certified by a registered professional engineer or architect which states that the proposed design and methods of construction are in conformance with the above referenced standards.
(5) The design and construction standards and specifications contained in Chapter 180, Construction Codes, Chapter 295, Historic Districts, and Chapter 302, House Numbering, shall be utilized.
C. Space below the lowest floor.
(1) Fully enclosed space below the lowest floor (excluding basements) which will be used solely for the parking of a vehicle, building access, or incidental storage in an area other than a basement, shall be designed and constructed to allow for the automatic entry and exit of floodwaters for the purpose of equalizing hydrostatic forces on exterior walls. The term "fully enclosed space" also includes crawl spaces.
(2) Designs for meeting this requirement must either be certified by a registered professional engineer or architect, or meet or exceed the following minimum criteria:
(a) A minimum of two openings having a net total area of not less than one square inch for every square foot of enclosed space;
(b) The bottom of all openings shall be no higher than one foot above grade;
(c) Openings may be equipped with screens, louvers, etc. or other coverings or devices, provided that they permit the automatic entry and exit of floodwaters.
D. Historic structures. See Part 22, Definitions, for requirements for the substantial improvement of any historic structures.
E. Accessory structures shall meet the requirements of these regulations.