No existing building or premises devoted to a nonconforming use shall be enlarged, extended, reconstructed, substituted or structurally altered except when changed to a conforming use, or when required to do so by law or order and as follows:
   (a)   Restoration.  Any nonconforming building or structure damaged less than fifty percent (50%) of its then-existing floor area or volume may be restored, reconstructed or used as before, provided that the volume of such use, building or structure shall not exceed the volume which existed prior to such damage, or as provided under Section 1157.04, and that it be completed within one year of such happening and provided that such restorations shall be in conformity with all other applicable requirements of the Zoning Ordinance.
   (b)   Displacement.  A nonconforming use shall not be extended to displace a conforming use.
   (c)   Change of Use.
      (1)   A nonconforming use or structure shall not be changed into a use which is first permitted in a less restrictive zoning district, except as follows.  In the case of existing buildings so designed and constructed to accommodate a use which becomes nonconforming upon the adoption of the Zoning Ordinance, such use may be continued.  If the present use is discontinued, the building may be reused for the same or similar type of operation or for a use permitted in the zoning district in which it is located.  In the case of vacant nonconforming buildings, such buildings or portions thereof may be reused or reoccupied for the same or similar type of occupancy for which it was built or for a use permitted in the zoning district in which it is located.
   In the event of abandonment or destruction of such buildings as described in this section, the provisions of Section 1157.03 shall apply.
      (2)   A nonconforming use may be changed into a conforming use.
      (3)   A nonconforming use which is not permitted in any district or which is permitted only as a special use may only be changed into a conforming one.
      (4)   When a nonconforming use is changed in accordance with the provisions hereof, the use of the building or other structure or tract of land shall not thereafter be changed again except in accordance with these regulations.
   (d)   Repairs.
      (1)   Normal maintenance and repairs and incidental alteration of a building or other structure containing a nonconforming use is permitted.
      (2)   A building or other structure containing residential nonconforming uses may be altered in any way to improve interior livability, provided that no structural alterations shall be made which would increase the number of dwelling units or the bulk of the building.
   (e)   Prior Approval.  Nothing herein contained shall require any change in the plans, construction or designated use of a building complying with existing laws, a permit for which had been duly granted and the construction of which has been started before the date of adoption of the Zoning Ordinance or any applicable amendment thereto, and the ground story framework of which, including the second tier of beams, has been completed within six months of the date of the permit, and which entire building has been completed according to such plans as have been filed, within one year of the date of adoption of the Zoning Ordinance or any applicable amendment thereto.
      (Ord. 58(72-73).  Passed 11-21-73.)