Nothing in this chapter shall prevent the restoration of a nonconforming building or use where less than 75% of the existing area of such building or structure destroyed by fire, explosion, act of God or act of public enemy or prevent the continuance of the use of such building or part thereof as such as existed at the time of such destruction of such building or part thereof or prevent a change of such existing use under the limitations provided in this chapter; but any building totally destroyed in the manner aforesaid may be reconstructed and thereafter used only in such a manner as to conform to all the provisions of this chapter. When 75% or more of the existing area of a nonconforming building or structure is destroyed by fire or other casualty or an act of God, the use of such nonconforming building or structure shall thereafter be terminated.

The owner of any nonconforming use that is partially destroyed as above mentioned must apply for a construction permit to rebuilding the nonconforming use within 12 months from the time of destruction. If the application to rebuilding the nonconforming use is filed after the above-mentioned twelve-month period, a construction permit shall only be issued for a conforming use.