If any nonconforming use of land is abandoned for any reason for a period of more than 12 consecutive months, any subsequent use of the land shall conform to the regulations for the district in which such land is located.

Any existing structure devoted to a use not permitted by this chapter in the district in which it is located shall not be enlarged, extended, constructed, reconstructed or structurally altered in any way except as may be required for normal maintenance or to prevent damage or injury. Such an existing nonconforming use in a structure may be changed to a use permitted in the district in which it is located. It is the intent of this article to discourage the continuance of nonconforming uses and structures.

Any structure or structure and land in combination, in or on which a nonconforming use is superseded by a permitted use, shall thereafter conform to the regulations for the district in which said structure is located; and the nonconforming use shall not thereafter be resumed.

When a nonconforming use of a structure or of a structure and premises in combination is discontinued or abandoned for 12 consecutive months or for 18 months during a three-year period, the structure or structure and premises in combination shall not thereafter be used except in conformance with the regulations of the district in which it is located.

A structure which, by reason of restriction on area, lot coverage, height, yards or other characteristics, could not be built under the terms of this chapter: