In any case where the applicant alleges that floor area is an inappropriate measure of the extent of damage or destruction, and elects to substitute reconstruction costs for floor area, an application may be made to the Board of Standards and Appeals to determine the extent of such damage or destruction.

If the Board finds that the costs of reconstructing the damaged or destroyed portion of such building to its previous condition exceed 50 percent of the costs of reconstructing the entire building to the condition existing on the date of such damage or destruction, the provisions of Section 52-531 (Permitted reconstruction or continued use) shall apply. In determining reconstruction costs, the cost of land shall be excluded.