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

Section 6.60.070 of the Alameda County Code is headed "Special provisions or exceptions," and that heading does the work people usually miss. Item E says the provisions of the noise chapter "shall not apply to noise sources associated with construction, provided said activities do not take place before seven a.m. or after seven p.m. on any day except Saturday or Sunday, or before eight a.m. or after five p.m. on Saturday or Sunday." So the weekday window runs 7:00 a.m. to 7:00 p.m., the weekend window is shorter at 8:00 a.m. to 5:00 p.m., and the chapter contains no separate provision prohibiting construction at other times.

The practical difference matters when a neighbour complains. A crew running a concrete saw at 2:00 p.m. on a Tuesday is inside item E, and the chapter's limits simply do not reach it, however loud it is. The same crew at 8:00 p.m. is not breaching a curfew, because there is no curfew: it has stepped outside the exemption, so its noise is now measured against the standards in Section 6.60.040, which the chapter applies to sound generally. That is a weaker restriction than a flat ban, and also a harder one to enforce, because it turns on measurement rather than on the clock.

Item F draws a contrast that is useful for homeowners. Maintenance of residential property, the mowing and leaf-blowing end of the spectrum, gets a wider exemption than construction: 7:00 a.m. to 9:00 p.m. on weekdays and 9:00 a.m. to 8:00 p.m. on Saturday and Sunday. A homeowner with a mower therefore has two more evening hours than a contractor with an excavator, and starts an hour later at the weekend.

Item G is the clawback, and it applies to construction and residential maintenance alike. No exemption is granted for an activity "where equipment used for those activities, including mufflers, is not maintained in the condition for which it was designed or intended and thereby unnecessarily increases noise levels so as to cause a noise disturbance or exceed the standards set forth in Section 6.60.040." A contractor working at 10:00 a.m. on a weekday with a failed muffler is inside the hours and still outside the exemption.

All of this governs unincorporated Alameda County only, which covers Castro Valley, San Lorenzo, Ashland, Cherryland and the other unincorporated communities. Oakland, Berkeley, Fremont, Hayward and every other incorporated city in the county set their own construction-noise rules, and this chapter does not reach them. Item C adds that the chapter does not apply where regulation has been preempted by state or federal law, and item D exempts public-agency and utility work such as street sweeping, limb removal, restoring electrical service and repairing hydrants, mains, sewers, roads and sidewalks, so a crew opening a street at night may sit outside the chapter for a different reason entirely.