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

The operative rule is Napa County Code section 8.16.080(B)(2)(a). It reaches any tools or equipment used in construction, drilling, repair, alteration or demolition work between seven p.m. and seven a.m. The rule applies when the sound creates a noise disturbance across a residential or commercial real property line, and section 8.16.020 defines a noise disturbance as any sound which exceeds the factors and quantitative standards of Sections 8.16.060 and 8.16.070. Section 8.16.020 defines construction as any site preparation, assembly, erection, substantial repair, alteration or similar action for or of public or private rights-of-way, structures, utilities or similar property. It defines demolition as any dismantling, intentional destruction or removal of structures, utilities, public or private right-of-way surfaces, or similar property.

A second layer sits in (B)(2)(b). Where technically and economically feasible, construction activities must be run so that maximum noise levels at affected properties stay within Table 8.16.080. From 7 a.m. to 7 p.m. the ceilings are 75 dBA residential, 80 dBA commercial and 85 dBA industrial. From 7 p.m. to 7 a.m. they fall to 60 dBA residential, 65 dBA commercial and 70 dBA industrial. The chapter defines residential, commercial and industrial areas by reference to Title 18 of the county code, zoning.

Homeowner tools run on a later clock. Subsection (B)(2)(a) does not apply to domestic power tools, and (B)(3)(a) separately bars operating a mechanically powered saw, sander, drill, grinder, lawn or garden tool, or similar tool between ten p.m. and seven a.m. so as to create a noise disturbance across a residential or commercial real property line. Under (B)(4), loading, unloading, opening, closing or other handling of boxes, crates, containers, building materials, garbage cans or similar objects between ten p.m. and six a.m. is also prohibited when it causes a noise disturbance across a residential real property line or at any time violates subsection (A) of section 8.16.060 or 8.16.070.

The code carves out several exceptions. Subsection (B)(2)(a) excepts emergency work of public service utilities and work done under a variance issued by the appropriate authority. Section 8.16.090 separately exempts emergency alerts and emergency work, warning devices such as sirens, licensed temporary events and roadway special events under Chapters 5.36 and 10.24, and equipment tied to agricultural operations on agricultural property, with wineries excluded. Section 8.16.090(D) lists construction and demolition among the activities that Table 8.16.070, the general exterior limits, does not cover.