The lawful use of a building or lot existing at the time of the adoption of this Chapter or, as applicable, of the adoption of any amendments to this Chapter may be continued as lawful even though such use does not conform with the provisions of this Chapter or applicable amendments thereto and provided that lawful non-conforming industrial or commercial uses may be enlarged up to fifty percent (50%) of their building area existing on the effective date of this Chapter or, as applicable, of the adoption of any amendments to this Chapter. 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 restrictive use classification. Whenever a non-conforming use of a building has been changed to a more restrictive use or to a conforming use, such changed use shall not thereafter be changed to a less restrictive use.

No building which has been damaged by fire, explosion, act of God or the public enemy to the extent of more than one hundred percent (100%) of the insured value shall be restored except in conformity with the regulations of this Chapter.

In the event that a non-conforming use of any building or lot is discontinued or its customary operation stopped for a period of one (1) year, regardless of any reservation of intent not to abandon or to resume such non-conforming use, the use of same shall thereafter conform to the regulations of the zoning district in which the building or lot is located. Any one (1) of the following circumstances shall be deemed discontinuance of a non-conforming use under this Subsection:

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.