A. Uses Allowed by Grandfather Clauses. The lawful use of any structure or land existing at the time of the enactment or subsequent amendment of this section may be continued although such structure or use does not conform with provisions of the chapter.
B. Extension. Preexisting nonconforming structures or uses may be extended or altered; provided, that no such extension or alteration shall be permitted unless there is a finding by the permit granting authority that such change, extension or alteration shall not be substantially more detrimental than the existing nonconforming use to the neighborhood.
C. Abandonment. A nonconforming use which has been abandoned for a period of more than two years shall not be reestablished unless there is a finding by the zoning board of appeals.
D. Changes. Once changed to a conforming use, no structure or land shall be permitted to revert to a nonconforming use.
E. The building commissioner may issue a building permit for any nonconforming structure to be reconstructed, extended, altered, or structurally changed upon a determination by the building commissioner that such proposed reconstruction, extension, alteration, or change does not increase the nonconforming nature of said structure, and the proposed changes otherwise conform with all other zoning requirements.
If the building commissioner determines that the proposed reconstruction, extension, alteration or change increases the nonconforming nature of the structure and/or does not otherwise conform with all zoning requirements, and the building commissioner does not issue a building permit, then the zoning board of appeals may authorize the proposed reconstruction, extension, alteration or change upon a determination that it is not substantially more detrimental than the existing nonconforming use to the neighborhood. [5-17-10 ATM; Art. XXV, 10-24-05 STM; Art. III, 4-4-88 STM, § IX(A).]