Except as provided in § 170-89, the lawful use of any building or land existing at the time of the enactment of this article may be continued although such use does not conform with the provisions of this article.

When a nonconforming use has been discontinued for a period of 12 consecutive months, such use shall not thereafter be reestablished, and any future use shall be in conformity with the provisions of this article.

No nonconforming use shall be changed to other than a conforming use for the district in which it is situated. Once changed to a conforming use, no building or land shall be permitted to revert to a nonconforming use.

Any nonconforming structure or portion thereof declared unsafe by a proper authority may be restored to a safe condition.

No nonconforming building damaged by fire or other causes to the extent of more than 75% of its latest market value prior to damage, as determined by the Code Enforcement Officer, shall be repaired or rebuilt except in conformity with the regulations of this article.

A nonconforming use shall not be extended. The extension of a lawful use to any portion of a nonconforming building which existed prior to the enactment of this article shall not be deemed the extension of such nonconforming use.

When the boundaries of a district are changed so as to transfer an area from one district to another district of a different classification, the foregoing provisions shall also apply to any nonconforming uses existing therein.