The provisions of this Section, inclusive, are optional, and are only applicable to zoning lots located wholly or partially within flood zones. The provisions of this Section, inclusive, may be applied to zoning lots with cottage envelope buildings. For such zoning lots, the underlying bulk regulations shall apply, except where permitted to be modified by this Section, inclusive.

No building that utilizes the provisions of this Section shall subsequently be enlarged pursuant to Section 73-622 (Enlargements of single- and two-family detached and semi-detached residences).