The provisions of this division shall apply to all existing buildings of wood-frame construction, or wood-frame portions thereof, where:
1. A permit for construction of a new building was applied for before January 1, 1978, or, if no permit can be located, the structure is determined by the Department to have been built under building code standards enacted before January 1, 1978; and
2. The ground floor portion of the structure contains parking or other similar open floor space that causes soft, weak or open-front wall lines, and there exists one or more stories above.
EXCEPTIONS: This division shall not apply to any building containing three dwelling units or less if the building is used solely for residential purposes. Moreover, notwithstanding any provision of this Code, compliance with this division shall not require existing electrical, plumbing, mechanical or fire-safety systems to be altered to comply with existing code unless they constitute a hazard to life or property.