San Francisco County Municipal Code Ch. 4 Special Detailed Requirements Based

ON USE AND OCCUPANCY SECTION 406 – MOTOR-VEHICLE-RELATED OCCUPANCIES 406.3 Add the following section: 406.3.4 Ventilation. Ventilation shall be provided as follows: Natural ventilation shall be required, and such space shall be provided with ventilation outlets in the walls or exterior doors. The total net area of such ventilation outlets shall be 200 square inches (0.129 m2) for a space up to 1,000 square feet (92.903 m2) in area and shall be increased 30 square inches (0.0194 m2) for each additional 200 square feet (18.58 m2) of floor area up to maximum floor area of 3,000 square feet (278.709 m2). SECTION 435 – SPECIAL PROVISIONS FOR LICENSED 24-HOUR CARE FACILITIES IN A GROUP R-2.1, R-3.1, R-4 435.3 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] SECTION 456 – FENCES 456 Add the following section: 456.1 Fences. Fences on any property containing a Group R Occupancy shall not be higher than 10 feet (3048 mm). Fences located less than 10 feet (3048 mm) from any public sidewalk shall not be higher than 10 feet (3048 mm) unless they are of open-type materials such as chain link fabric. Fence height shall be measured from the level of general existing adjacent ground of the general area prior to the improvement of the properties. A fence or railing placed on top of the retaining wall shall be measured from the top of the wall. Fences constructed wholly or in part of barbed wire are prohibited, except when permitted with the express written permission of the Building Official, and the Fire Department in the following situations:

1. On top of a fence more than 7 feet (2.134 m) high, protecting a dangerous or hazardous area.
2. Within a private area, enclosed by a seven-foot-high (2.134 m) fence, such that entry to the area is limited by the outer, nonbarbed fence.
3. In special instances for localized protection, and in areas within or atop a building to isolate dangerous conditions.