1206.2.1 Rear yard access for multiple dwellings.
BC § 1206.2.1
For multiple dwellings, there shall be direct access from the street to every rear yard through a noncombustible 2-hour fire-resistance-rated passage either in a direct line or through a court, except that the passage may be 1-hour fire-resistance-rated for dwellings not exceeding three stories in height and occupied by not more than 2 families on any story. Such passage shall be at least 36 inches (914.4 mm) in clear width and 7 feet (2133.6 mm) in height. Exceptions. No such passage shall be required for: 1. Buildings of Type IA or IB construction.
2.Buildings not exceeding three stories in height, and occupied by not more than one family on any story nor more than three families in all.
3.Buildings not exceeding two stories in height, and occupied by not more than two families on any story nor more than four families in all.
