Additions. A nonconforming building or use shall not be added to or enlarged in any way that will extend the nonconforming features unless such nonconforming building or use is made to conform to the regulations of the district in which it is located.

Alterations. A nonconforming building or use may not be reconstructed or structurally altered in any manner that will allow or encourage an expansion or increment in any nonconforming feature, unless such building or use is altered to conform to the regulations of the district.

Changes. A nonconforming use may not be changed to another nonconforming use under the provisions of this section.

Discontinuance. Whenever a nonconforming use has been discontinued for a period of one year, any future use shall be in conformity with the provisions of this chapter. A use shall be deemed to have been discontinued under any of the following conditions:

Restoration. A nonconforming structure or use which has been damaged by fire or other natural causes may be restored, reconstructed or used as before, provided that the height and area shall not exceed that which existed before said damage, and further is authorized by the Board of Appeals. Said restoration must be completed within two years of such occurrence and a certificate of occupancy has been issued therefor or the building or use shall not continue as a legal nonconforming situation.

Removal or replacement. A nonconforming structure or use, once removed, shall not be reintroduced or replaced other than by a conforming structure or use.

Buildings which are nonconforming as to yard, height or coverage regulations. Buildings occupied by a use permitted in the district in which they are located, but which do not conform to yard, height, or coverage regulations, may be permitted to be expanded by the Zoning Board without a finding of significant economic injury, provided the expansion does not involve any dimensional feature which makes worse the existing nonconforming dimensions.