Sonoma County, CA Noise Ordinances: Construction Hours (2026)

Sonoma County's Noise Element (Policy NE-1f and supporting policies, General Plan adopted 2008, amended 2012) exempts construction activity from the Table NE-2 numeric noise limits when it occurs during permitted hours, but conditions that exemption on the contractor using properly maintained equipment with manufacturer-supplied mufflers and intake silencers, staging equipment as far as feasible from sensitive receivers, and not exceeding the noise levels assumed in the project's environmental review. Permit Sonoma's standard use-permit and grading-permit conditions, and the County's construction-noise mitigation measures applied through CEQA review, typically limit hours to 7:00 a.m. to 7:00 p.m. (or to one hour before sunset, whichever is earlier) Monday through Saturday, with no construction on Sundays or holidays without a special variance. The General Plan Noise Element specifically lists Sunday and federal holidays - New Year's Day, MLK Day, Presidents Day, Memorial Day, Independence Day, Labor Day, Veterans Day, Thanksgiving, and Christmas - as days when normal construction is prohibited. Emergency repairs, public-utility emergency work, and owner-occupied minor interior projects that don't require a building permit may proceed outside these hours. Noise-sensitive land uses defined in the Noise Element include residences, hospitals, schools, churches, libraries, nursing homes, and outdoor public-assembly areas. After 7:00 p.m. and on Sundays/holidays, construction noise becomes subject to the full Noise Element limits - 50 dBA L50 in the evening hours before 10 p.m. and 45 dBA L50 from 10 p.m. to 7 a.m. - and to the general nuisance prohibition of Sonoma County Code Sec. 3-41. Special major-project conditions can also impose tighter hours, particularly in rural agricultural areas (LIA, LEA, DA, RRD) near vineyards during harvest, in coastal zone parcels, and in fire-rebuild areas after the 2017 Tubbs, 2019 Kincade, and 2020 Glass fires where rebuilding densities concentrated construction in residential neighborhoods like Coffey Park (Santa Rosa) and unincorporated Mark West Springs and Larkfield-Wikiup. Caltrans and County roadway-construction projects, water and sewer utility work, and PG&E undergrounding projects can obtain night-work variances from Permit Sonoma and the Department of Transportation and Public Works when daytime work would create traffic-safety conflicts. The City of Sonoma, City of Santa Rosa, City of Petaluma, and other incorporated cities have their own construction-hour ordinances - for example, City of Sonoma Municipal Code 9.56.040 limits construction to 7 a.m. - 6 p.m. weekdays and 9 a.m. - 5 p.m. Saturday with no Sunday work - and County rules do not preempt them.