While the granting of variances generally is limited to a lot size
less than 1/2 acre, deviations from that limitation may occur. However,
as the lot size increases beyond 1/2 acre, the technical justification
required for issuing a variance increases. Variances may be issued
by the Board of Zoning Appeals for new construction and substantial
improvements to be erected on a lot of 1/2 acre or less in size contiguous
to and surrounded by lots with existing structures constructed below
the base flood level, in conformance with the provisions of this section.