Section 317

ROOFTOP GARDENS AND LANDSCAPED ROOFS

be installed and maintained in accordance with Sections 317.2 through 317.5 and Sections 1505 and 1507.16 of the California Building Code.

garden or landscaped roof areas shall not exceed 15,625 square feet (1450 m ² ) in size for any single area with a maximum dimension of 125 feet (39 m) in length or width. A minimum 6-foot-wide (1.8 m) clearance consisting of a Class Arated roof system complying with ASTM E108 or UL 790 shall be provided between adjacent rooftop gardens or landscaped roof areas.

vegetated roofing systems abutting combustible vertical surfaces, a Class A-rated roof system complying with ASTM E108 or UL 790 shall be achieved for a minimum 6-footwide (1829 mm) continuous border placed around rooftop structures and all rooftop equipment including, but not limited to, mechanical and machine rooms, penthouses, skylights, roof vents, solar panels, antenna supports and building service equipment.

Vegetation shall be maintained in accordance with Sections 317.4.1 and 317.4.2.

317.4.1 Irrigation. Supplemental irrigation shall be provided to maintain levels of hydration necessary to keep green roof plants alive and to keep dry foliage to a minimum.

317.4.2 Dead foliage. Excess biomass, such as overgrown vegetation, leaves and other dead and decaying material, shall be removed at regular intervals not less than two times per year.

317.4.3 Maintenance plan. The fire code official is authorized to require a maintenance plan for vegetation placed on roofs due to the size of a roof garden, materials used or where a fire hazard exists to the building or exposures due to the lack of maintenance.

roofs and used for the care and maintenance of vegetation on roofs shall be stored in accordance with Section 313.

GENERAL REQUIREMENTS