Ada County, ID Noise Ordinances: Decibel Limits (2026)

Ada County's general noise ordinance does not use a sound-level meter test. Code 5-13-3(A) instead measures a violation by audibility and distance: noise is unlawful once it is plainly audible within any residence or business, other than the source of the sound, or upon a public right-of-way or street at a distance of one hundred feet or more from the source, and only during the county's overnight hours of 10:00 p.m. to 7:00 a.m. There is no county-issued decibel meter reading required to cite a violation; an officer's determination that the sound crossed the 100-foot threshold or carried into a neighboring building is enough.

Two seasonal exceptions shift the start of the restricted period. Under 5-13-3(B) and (C), construction noise and landscape maintenance noise may both begin at 6:00 a.m. rather than 7:00 a.m. during June, July and August because of the region's summer heat, so a landscaping crew or construction site can legally run an hour earlier than other noise sources for three months a year.

Ada County does use an actual decibel figure elsewhere in its code, just not for this general ordinance: Ada County Code 2-2-6(H) caps radios and sound amplification devices on county parks and waterways property at 62 decibels measured 20 feet from the source, a park-specific standard separate from the countywide plainly-audible test. Outside a facility-specific rule like that one, a resident's only path to a numeric standard is Section 5-13-4's exemption and waiver process, which lets the Board grant a resolution-based exemption or a 30-day-advance temporary waiver rather than set a fixed dBA ceiling.