The lawful use of a building existing at the time of the adoption of this Article may be continued, even though such use does not conform with the provisions hereof.

If no structural alterations are made, a non-conforming use of a building may be changed to another non-conforming use of the same or more restricted classifications. Whenever a non-conforming use of a building has been changed to a more restricted use or to a conforming use, such use shall not thereafter be changed to a less restricted use.

Whenever the use of a building becomes non-conforming through a change in the Zoning Code or district boundaries, such use may be continued and, if no structural alterations are made, it may be changed to another non-conforming use of the same or a more restricted classification.

When a building, the use of which does not conform to the provisions of this Chapter, is damaged by fire, explosion, act of God or the public enemy to the extent of more than seventy-five percent (75%) of its fair market value, it may be restored only by action of the Board of Adjustment as set forth in Article XII "Board Of Adjustment" of this Chapter.

In the event that a non-conforming use of any building or premises is discontinued or its normal operation stopped for a period of six (6) months, the use of the same shall thereafter conform to the use regulations in the district in which it is located.

A non-conforming use occupying only a portion of a building may be extended throughout the building if the same has been lawfully acquired and actually devoted to such use previous to the adoption of this Chapter or to any affecting amendments thereof.

No existing building devoted to a use not permitted by this Chapter in the district in which such building is located, except when required to do so by law or order, shall be enlarged, extended, reconstructed or structurally altered, unless such use is changed to a use permitted in the district in which such building is located. Non-conforming use buildings may be extended or enlarged or structurally altered or reconstructed by not to exceed a fifty percent (50%) increase in the cubical contents of the building as of the effective date of this Chapter, if a special use permit therefor be granted under Article VI "Special Use Regulations" of this Chapter, provided that all height and area regulations be observed in any such extension or enlargement or alteration.

Any mobile home located in a district other than a mobile home park district from and after the effective date of this Chapter shall be considered as a non-conforming use of the land under the provisions of this Chapter; provided however, that the replacement of a mobile home with a new mobile home, permanently affixed to a continuous permanent perimeter foundation, meeting all setback requirements of "R-1" single-family requirements, by an owner occupying an existing mobile home under the provisions of the special use regulations of this Chapter shall not be considered such a change so as to alter the pre-existing non-conforming use.