Union City, CA Noise Ordinances: Construction Hours (2026)
Construction hours in Union City, CA, sometimes called construction noise rules or contractor work-hour ordinances, set when contractors can run power tools, hammers, and heavy equipment.
Key Facts
- Governing section
- UCMC § 9.40.053(A)-(B)
- Per-equipment limit
- 83 dBA at 25 feet
- Property plane limit
- 86 dBA at any point outside the property plane
- Indoor equipment
- measured outside the structure
- Permit required
- Valid City construction permit
- Adopted
- Ord. 275-86 § 1, 1986
Summary
Union City caps each piece of permitted construction equipment at 83 dBA measured 25 feet away, or 86 dBA at any point outside the project's property plane. The limits in § 9.40.053 apply even when the work holds a valid City permit and runs during allowed hours.
No individual piece of equipment shall produce a noise level exceeding eighty-three dBA at a distance of twenty-five feet. If the device is housed within a structure on the property, the measurement shall be made outside the structure at a distance as close to twenty-five feet from the equipment as possible.
B. The noise level at any point outside the property plane of the project shall not exceed eighty-six dBA. (Ord. 275-86 § 1, 1986)
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: rev 4940544; v16 updated 2026-06-23).
Full Breakdown
Union City Municipal Code § 9.40.053 applies to construction, alteration, or repair work carried out under a valid City permit. Holding the permit and working during the allowed hours is not enough by itself. The work must also meet one of two noise limitations, written into subsections A and B.
Subsection A measures at the machine. No individual piece of equipment may produce a noise level exceeding eighty-three dBA at a distance of twenty-five feet. The limit is written per piece of equipment, so each machine on a Union City job site is tested on its own reading.
The section also says what to do when a machine cannot be measured in the open. If the device is housed within a structure on the property, the measurement is made outside the structure, at a distance as close to twenty-five feet from the equipment as possible. What counts is the sound that reaches the outside of the building, not the sound beside the machine indoors.
Subsection B measures at the edge of the project. The noise level at any point outside the property plane of the project shall not exceed eighty-six dBA. This test is not tied to a single machine. It is tied to a place, and the place can be any point outside the property plane.
The limits work together. A contractor whose equipment stays at or under 83 dBA at 25 feet meets the limitation in subsection A. A contractor with a louder machine can still comply if the level outside the property plane stays at or under 86 dBA. Equipment that exceeds both thresholds is out of compliance even during permitted hours.
The limits come from Ord. 275-86 § 1, adopted in 1986. The Planning Department fields complaints under § 9.40.070, and a noise reduction plan can be required under § 9.40.090.
Violations & Fines
A noise disturbance violation under Chapter 9.40; the Planning Department fields complaints under § 9.40.070 and can require a noise reduction plan under § 9.40.090.
Frequently Asked Questions
Does a construction permit exempt equipment from any noise limit?
Where is equipment noise measured from?
Is the 83 dBA limit for the whole site or for each machine?
Who handles a construction noise complaint in Union City?
Sources & Official References
Other rules in Union City
California rules heatmap·Compare Union City to another location·View the California noise ordinances overview
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Construction Hours in Nearby Cities
How other cities in Alameda County handle construction hours.