The provisions of Chapter 34 of the Ohio Building Code shall control the alteration, repair, addition, and change of occupancy of any existing structure.
   The occupancy of any structure currently existing on the date of adoption of this Code shall be permitted to continue without change provided the alleged occupancy can be shown to have existed for more than two years and there are no orders of the Building Official pending, no evidence of fraud, or no serious safety or sanitation hazard.
   Buildings constructed in accordance with plans which have been approved prior to the effective date of this Code are existing buildings.
(OBC 102.6)