Generators are louder than you think — here's how loud.
Modern standby generators run quieter than older models, but they're not silent. Marin neighbors and setback requirements matter — plan location and mitigation early.
By Steven Lockhart · Reviewed by Alex Towery, C-10 #989290
Updated 2026-06-16
Modern standby generators (Generac, Kohler, Cummins residential models) operate at 65-78 dB at 23 feet — quieter than older models but audible from neighbor properties. Marin AHJs have specific setback requirements (typically 5-10 feet from property line, 5+ feet from windows, varies by jurisdiction). Noise mitigation options: location selection (back of house, against masonry walls), sound-attenuating enclosures (manufacturer or aftermarket), exercise-cycle timing (set to weekday daytime). Plan location and mitigation during initial design, not retroactively.
01How loud generators actually are.
Modern residential standby generators run at 65-78 dB measured at 23 feet — about the volume of normal conversation to a vacuum cleaner. Older generators (10+ years old designs) run 80-90 dB and noticeably louder. The Generac Guardian series (most popular in Marin) is rated 65-72 dB depending on size; Kohler 14RESAL is rated 69 dB; Cummins QuietConnect models advertised at 65-70 dB. These ratings assume manufacturer-installed sound attenuation and load-rated operation.
Real-world sound varies. Generators run louder at start-up (often 80+ dB momentarily) before settling to operational dB. Sound carries further at night when ambient noise is low. Hilly Marin terrain reflects sound unpredictably — generators in canyons or against hard surfaces can sound louder at neighbor properties than open-yard installations. Weekly exercise cycles (factory-set to specific weekday/time) are the most predictable noise event; for the rest of the time, generators only run during outages.
02Setback requirements and neighbor considerations.
Marin AHJ setback requirements
Vary by jurisdiction. Common requirements: 5-10 feet from property line, 5+ feet from any window of habitable space, 10+ feet from doors and air intakes. Some jurisdictions require larger setbacks for noise reasons. Verify specific setbacks with local AHJ during planning — we typically pull this info as part of permit review.
Neighbor relationship management
Even within code-compliant setbacks, neighbors near the generator location experience noise during operation. Best practice: discuss generator plans with adjacent neighbors before install. Generator runs primarily during outages (when neighbors also have no power, less noise sensitivity) plus weekly exercise cycle (a single noticeable event). Most Marin neighbors accept generators reasonably.
Exercise cycle scheduling
Factory-set exercise cycles default to Wednesday or other weekday at noon-ish. Can be reconfigured during commissioning to fit homeowner preferences. Don't set exercise for evenings, weekends, or early morning hours when neighbor sensitivity is highest. Many Marin homeowners choose Wednesday or Thursday at 11 AM for minimal disruption.
03Noise mitigation strategies.
Location is the most powerful mitigation tool. Generators located on the side of the house away from neighbors (when geometry allows), against masonry walls (which absorb sound vs reflecting), behind landscaping (modest sound dampening from dense plantings) all reduce neighbor noise impact. We discuss optimal location during planning visit and recommend based on lot geometry, neighbor positions, and HVAC equipment positions (already-noisy areas).
Sound-attenuating enclosures add ~$1,500-$3,500 to install cost and reduce dB by 5-10 dB in well-designed setups. Worth considering for homes with close-proximity neighbors, urban Marin lots where geometry can't optimize location, or homeowners particularly sensitive to neighbor relations. Generac, Kohler, and Cummins offer manufacturer-matched enclosures; aftermarket options exist but require careful airflow design to prevent generator overheating. For most Marin installs, standard manufacturer enclosure plus thoughtful location selection achieves acceptable neighbor noise levels without aftermarket enclosure.
Common questions.
Are generators required to be quieter at night?
Marin AHJs and unincorporated areas have noise ordinances that limit nighttime noise levels from any source, including generators. Standby generators are exempt from many ordinances during actual emergency operation (outages), but weekly exercise cycles and any unusual extended runs fall under normal noise rules. Setting exercise cycles for weekday daytime hours keeps you within all reasonable noise expectations.
Will my neighbor's complaints prevent installation?
Rarely. As long as the install meets AHJ setback and code requirements, neighbor complaints typically don't block permits. However, ongoing operation can generate complaints leading to noise ordinance enforcement if generator significantly exceeds dB limits during exercise or unusual extended use. Prevention strategy: communicate with adjacent neighbors before install, optimize location for minimum neighbor noise, schedule exercise cycles thoughtfully.
Does the generator type/brand affect noise meaningfully?
Yes, modestly. Generac Guardian, Kohler 14RESAL series, and Cummins QuietConnect are all designed with noise reduction as priority — typically 65-72 dB at 23 feet. Less-expensive or older designs run 75-85 dB. Diesel generators run louder than gas (5-10 dB higher typically). The dB difference between premium-quiet and standard residential models is meaningful for close-proximity installations but rarely the deciding factor for homeowners.
Can I make my existing generator quieter?
Yes — retrofit sound-attenuating enclosures exist for major generator brands. Cost $1,500-$3,500 installed depending on generator size and brand. Effectiveness: typically 5-10 dB reduction. Worth considering for installations with ongoing neighbor noise concerns or homeowners who didn't prioritize noise during original install. We can install retrofit enclosures or coordinate with manufacturer suppliers.
How do you handle pricing — flat fee or hourly?
Both, depending on scope. Routine service calls and predictable scope (panel replacement, EV charger install, transfer switch install, fixture replacement) are flat-fee quoted up front. Diagnostic visits and emergency scope are hourly because we don't know what we'll find. Either way, you get a written quote before work starts on anything significant, and we don't proceed beyond the quote without your sign-off.
How quickly can you schedule?
Depends on scope and season. Emergency dispatch: same-day across Marin County (1-3 hours business hours, 1-4 hours after-hours). Same-day standard service: 3-6 hours from call when capacity allows; otherwise next business day. Scheduled service work: 1-3 weeks typical. Larger projects requiring permits and PG&E coordination: 4-12 weeks depending on scope. We're upfront about timeline at the quote stage.
What warranty do you offer on work?
Our standard residential warranty: 2 years on labor, manufacturer warranty on parts (varies by product — typically 1-10 years). Major installs (panels, generators, EV chargers) often have longer manufacturer warranties (5-10 years). If there's an issue with our work in the warranty period, we come back and fix it at no cost. We also stand behind work past warranty — repeat customers and referrals matter more than a transactional fix.
Are you licensed and insured?
Yes. California State License Board C-10 Electrical Contractor #989290, in good standing. Carry general liability insurance and workers' compensation insurance as required by California law. Bondable on projects requiring it. Happy to provide proof of insurance to clients or property managers on request. License lookup: cslb.ca.gov.
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Family-run, C-10 #989290, 20+ years in the trade. Honest scoping, fair pricing, work that lasts.