§ 252-18. Specific standards.

In all areas of special flood hazards where base flood elevation data have been provided as set forth in § 252-3, Basis for establishing areas of special flood hazard, or in § 252-10, Use of other base flood and floodway data, the following standards are required:

A. 

Residential Construction. For Coastal A Zone construction, see § 252-19, Coastal high-hazard area and Coastal A Zone.

(1) 

New construction and substantial improvement of any residential structure located in an A or AE Zone shall have the lowest floor, including the basement together with the attendant utilities (including all electrical, heating, ventilating, air-conditioning and other service equipment) and sanitary facilities, elevated at or above the base flood elevation plus two feet or as required by ASCE/SEI 24-14, Table 2-1, whichever is more restrictive;

(2) 

Require within any AO or AH Zone on the municipality's DFIRM that all new construction and substantial improvement of any residential structure shall have the lowest floor, including the basement together with the attendant utilities and sanitary facilities, elevated above the depth number specified in feet plus two feet above the highest adjacent grade (at least three feet if no depth number is specified). And, require adequate drainage paths around structures on slopes to guide floodwaters around and away from proposed structures.

B. 

Nonresidential construction. In an area of special flood hazard, all new construction and substantial improvement of any commercial, industrial or other nonresidential structure located in an A or AE Zone (for Coastal A Zone construction see § 252-19, Coastal high-hazard area and Coastal A Zone) shall have the lowest floor, including the basement together with the attendant utilities and sanitary facilities as well as all electrical, heating, ventilating, air-conditioning and other service equipment either:

(1) 

Elevated to or above the base flood elevation plus two feet or as required by ASCE/SEI 24-14, Table 2-1, whichever is more restrictive; and

(2) 

Require within any AO or AH Zone on the municipality's DFIRM to elevate above the depth number specified in feet, plus two feet, above the highest adjacent grade (at least three feet if no depth number is specified). And, require adequate drainage paths around structures on slopes to guide floodwaters around and away from proposed structures; or

(3) 

Be floodproofed so that below the base flood level plus two feet or as required by ASCE/SEI 24-14, Table 6-1, whichever is more, the structure is watertight with walls substantially impermeable to the passage of water;

(4) 

Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy; and

(5) 

Be certified by a registered professional engineer or architect that the design and methods of construction are in accordance with accepted standards of practice for meeting the applicable provisions of this subsection. Such certification shall be provided to the official as set forth in § 252-11B(2).

C. 

Manufactured homes. Manufactured homes shall be anchored in accordance with § 252-17A.

(1) 

All manufactured homes to be placed or substantially improved within an area of special flood hazard shall:

(a) 

Be consistent with the need to minimize flood damage;

(b) 

Be constructed to minimize flood damage;

(c) 

Have adequate drainage provided to reduce exposure to flood damage;

(d) 

Be elevated on a permanent foundation such that the top of the lowest floor is at or above the base flood elevation plus two feet or as required by ASCE/SEI 24-14, Table 2-1, whichever is more restrictive; and

(e) 

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 be securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement.