Any nonconforming structure or use damaged to less than 80% of its previous existing area may be restored, reconstructed or used as before, provided the area of such use, building or structure shall not exceed the area which existed prior to such damage nor increase the intensity of use. The Board of Adjustment shall determine the time period in which complete restoration shall take place.

Repairs. Normal maintenance and repair of a structure containing a nonconforming use is permitted, provided that it does not extend the area or volume of space occupied by the nonconforming use and does not increase the number of dwelling units or increase the intensity of use.

Nothing in this chapter shall prevent the strengthening or restoring to a safe or lawful condition any part of any building or structure declared unsafe or unlawful by the Construction Official or other authorized State or Town official.