The following provisions shall apply whenever any improvement is made to an existing structure located within the Floodplain Overlay Zone:
A. No expansion or enlargement of an existing structure shall be allowed within the Floodway Subdistrict that would cause any increase in BFE.
B. No expansion or enlargement of an existing structure shall be allowed within the Zone AE Without Floodway Subdistrict or the Zone A Subdistrict that would, together with all other existing and anticipated development, increase the BFE more than one foot at any point.
C. Any modification, alteration, reconstruction, or improvement, of any kind to an existing structure, to an extent or amount of 50% or more of its market value, shall constitute a substantial improvement and shall be undertaken only in full compliance with § 600-1823 and all other applicable provisions of this Part.
D. The above activity shall also address the requirements of the 34 Pa. Code, as amended and the 2009 IBC and the 2009 IRC.