The lawful use of a “building” existing at the time of this ordinance may be continued, although such use not conform with the provisions hereof, and such use may be extended throughout the building provided no structural alterations, except those required by law or ordinance, are made therein. If no structural alterations are made, a nonconforming use of a building may be changed to another nonconforming use of the same or more restricted classification. If such nonconforming building is removed, every future use of such premises shall be in conformity with the provisions of this ordinance.

Repairs and alterations may be made to a legal nonconforming building, provided that no structural alterations shall be made except those required by law or ordinance, unless the building is changed to a conforming use and provided that no additional dwelling units shall be added where the nonconforming use results from there being more dwelling units on the lot than is permissible in the district in which the building is located. The Board of Adjustment shall have the authority after the hearing to grant extension of a building nonconforming as to uses not to exceed twenty-five percent (25%) of the ground area of the same in case of evident hardship, subject to the yard restrictions herein provided.

The lawful use of “land” existing at the time of the passage of this ordinance, although such does not conform to the provisions hereof, may be continued, but if such nonconforming use is discontinued, any future use of said premises shall be in conformity with the provisions of this ordinance.

A legal nonconforming use, if changed to conforming use, may not thereafter be changed back to a nonconforming use. A legal nonconforming use, if changed to a more restricted nonconforming use, may not thereafter be changed unless to an equal or to a more restricted use.

A legal nonconforming use, when discontinued or abandoned, shall not be resumed, except that the existing yards for all single-family residences existing at the time of the passage of this ordinance shall be deemed to be conforming. Discontinuance or abandonment shall be defined as follows:

Upon evidence of hardship, the Board [of] Adjustment shall have the power to extend the time limits in paragraph 5 above not to exceed six (6) months.

If a building occupied by nonconforming use is destroyed by fire or the elements, it may not be reconstructed or rebuilt except to conform with provisions of this ordinance. In the case of partial destruction by fire or other causes, not exceeding fifty (50) percent of its value, the Building Inspector may issue a permit for reconstruction. If greater than fifty (50) percent and less than total, the Board of Adjustment may grant permit for repair after public hearing, having due regard for the property rights of the persons affected when considered in the light of the public welfare and the character of the area surrounding the designated nonconforming use and the conservation and preservation of property.

A certificate of occupancy shall be issued for all legal nonconforming uses.

Nothing herein contained shall require any change in the plans, construction or designated use of a building for which a legal building permit has been heretofore issued, provided such construction shall have been started and shall be diligently prosecuted to completion.

The lawful location and maintenance of commercial signboards and billboards existing at the time of the passage of this ordinance may be continued, although such use does not conform with the provisions hereof, provided, however, that no structural alterations are made therein and provided, however, any sign installed and in use prior to the enactment of this ordinance will not be restricted by the ordinance so long as its location, height, basic construction, and other significant characteristics remain unchanged. Any sign in any zoning district which is rebuilt, relocated, modified, enlarged, extended, [or] altered other than by normal maintenance to the configuration existing at the time of enactment of this ordinance shall be regulated by this ordinance.

The foregoing provisions of Section 22 shall also apply to uses, yards, or buildings made nonconforming by subsequent amendments to zoning regulations.