435.3 Add the following section:
435.3.5 For detached one- and two-family dwellings, and townhouses not more than three stories above grade plane in height with a separate means of egress, buildings housing protective social-care homes or in occupancies housing inmates who are not restrained need not be of one-hour fire-resistive construction when not more than two stories in height. In no case shall individual floor areas exceed 3,000 square feet (279 m2). The fire-resistive protection of the exterior walls shall not be less than one hour where such walls are located within 5 feet (1524 mm) of the property line. Openings within such walls are not permitted. Openings within non-rated walls need not be protected. [California Residential Code Section R335.9]