148

SEC. 148. REDUCTION OF GROUND-LEVEL WIND CURRENTS FOR BUILDINGS TALLER THAN 85 FEET IN CERTAIN DISTRICTS. (a) Applicability. In the C-3 Districts, Van Ness Special Use District, Folsom and Main Residential/Commercial Special Use District, Downtown Residential (DTR) Districts, and Central SoMa Special Use District, this Section 148 shall apply to new buildings taller than 85 feet in Height, vertical additions of more than 30 feet resulting in a total building height greater than 85 feet, or vertical additions of more than 30 feet to an existing building that is taller than 85 feet. Building height for the purpose of applicability of this Section shall be calculated pursuant to the provisions of Sections 260 and 263.21. (b) Definitions. “Equivalent Wind Speed” means an hourly average wind speed adjusted to incorporate the effects of gustiness or turbulence on pedestrians, pursuant to the methodology adopted by the Planning Commission, as amended from time to time. “Nine-Hour Hazard Criterion” means a ground-level equivalent wind speed of 26 miles per hour for nine or more hours per year. (c) Controls for Hazardous Winds. Projects shall not result in any net new locations that exceed the Nine-Hour Hazard Criterion. (d) Wind-reducing Features. All wind-reducing features necessary to meet the requirements of this Section 148 shall be identified on the approved project plan set. (e) Maintenance of Wind-reducing Features. All wind-reducing features necessary to meet the requirements of this Section 148 must be maintained for the life of the project. The Zoning Administrator may approve, including after installation, substitution of alternate wind-reducing features that would have an equal or superior effect on reducing ground-level winds at the subject location, provided that such features do not conflict with or increase noncompliance with other provisions of the Planning Code or other adopted Citywide Design Standards. (Added by Ord. 414-85, App. 9/17/85; amended by Ord. 188-15 , File No. 150871, App. 11/4/2015, Eff. 12/4/2015; Ord. 245-25, File No. 250701, App. 12/12/2025, Eff. 1/12/2026, Oper. 1/12/2026) AMENDMENT HISTORY Nonsubstantive changes; Ord. 188-15 , Eff. 12/4/2015. Section header amended; divisions (a)- (c) deleted; new divisions (a)-(e) added; Ord. 245-25, Eff. 1/12/2026. SEC. 149. [REDESIGNATED.]