Noise Ordinances in Longmont, CO (2026)
9 verified noise ordinances for Longmont, Colorado, sourced directly from the municipal code and official government pages.
Verified from official government sources
Quiet Hours
Longmont's quiet hours run from 10:00 p.m. to 7:00 a.m. under LMC § 10.20.100 and § 10.20.110, when nighttime sound limits apply and many residential activities become prima facie unreasonable noise if audible 25 feet from the source or inside a neighbor's home.
Longmont Quiet Hours
Some RestrictionsConstruction Hours
Under LMC § 10.20.110(D)(4), construction activity in a residential area or within 500 feet of a school is prohibited between 7:00 p.m. and 7:00 a.m. Monday through Saturday and before 9:00 a.m. on Sundays, unless temporarily approved by the economic development director.
Longmont Construction Hours
Some RestrictionsBarking Dogs
Longmont treats persistent animal noise as a public nuisance under LMC § 7.04.130. An owner who allows a pet to habitually bark, howl, yelp, or otherwise disturb a neighborhood faces enforcement by Longmont Police Animal Control.
Longmont Barking Dog Ordinance
Some RestrictionsLeaf Blower Rules
Longmont does not ban leaf blowers, but LMC § 10.20.110(D)(3) restricts homeowner power equipment — including leaf blowers — to the hours of 7:00 a.m. to 10:00 p.m. and requires equipment mufflers to be in good working condition.
Longmont Leaf Blower Rules
Few RestrictionsAmplified Music & Events
Under LMC § 10.20.100(A), amplified sound is prima facie unreasonable noise at any time of day if it is audible 25 feet from the source or inside a private residence the responsible person has no right to occupy. Permitted special events may produce up to 80 dB at the permit perimeter.
Longmont Amplified Music Rules
Some RestrictionsAircraft Noise
Longmont does not separately regulate aircraft overflight noise. Aircraft operations are pre-empted by federal law administered by the Federal Aviation Administration (FAA), so the city's noise ordinance (LMC § 10.20.100 / § 10.20.110) cannot be applied to in-flight aircraft.
Longmont Aircraft Noise
Few RestrictionsIndustrial Noise
LMC § 10.20.110 caps noise at 75 dB(A) in industrial zones day or night, measured at least 25 feet from the source. Industrial operations including railroad rights-of-way must keep noise below this ceiling regardless of time of day.
Longmont Industrial Noise Limits
Some RestrictionsDecibel Limits
LMC § 10.20.110 sets dB(A) ceilings measured at least 25 feet from the source: residential 50 night / 55 day, commercial 55 night / 65 day, industrial 75 day and night. Mixed-use dwellings on a non-residential lot are treated as commercial.
Longmont Decibel Limits
Some RestrictionsOutdoor Music
Outdoor amplified music in Longmont is regulated through LMC § 10.20.100(A) (amplified-sound prohibition audible at 25 feet) combined with the LMC Chapter 13.37 'use of public places' permit, which allows up to 80 decibels at the permit perimeter for authorized special events.
Longmont Outdoor Music & Events
Some RestrictionsLooking for Boulder County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Longmont city rules.
Noise Ordinances in Boulder County →