Quiet Hours: Altadena vs Santa Monica
How do quiet hours rules compare between Altadena, CA and Santa Monica, CA?
Altadena has fewer restrictions than Santa Monica.
Altadena, CA
Los Angeles County
Altadena is unincorporated, so LA County Title 12 Chapter 12.08 (Noise Control) applies. Nighttime exterior limits run 10:00 p.m. to 7:00 a.m. with stricter dB caps; daytime runs 7:00 a.m. to 10:00 p.m.
View full Altadena rules →Santa Monica, CA
Los Angeles County
Santa Monica enforces quiet hours from 10 PM to 7 AM on weekdays and 10 PM to 8 AM on weekends/holidays. During quiet hours, residential noise limits drop to 50 dBA (15-minute Leq). Sound amplifying equipment in parks and on beaches is prohibited after 10 PM.
View full Santa Monica rules →Key Facts Comparison
| Fact | Altadena | Santa Monica |
|---|---|---|
| Code Section | LA County Code Ch. 12.08 (Title 12) | - |
| Nighttime Window | 10:00 p.m. – 7:00 a.m. | - |
| Residential Night Limit | 45 dBA (R-1) | - |
| Residential Day Limit | 50 dBA (R-1) | - |
| Ambient Exceedance Rule | +5 dB over ambient | - |
| Weeknight | - | 10 PM – 7 AM |
| Weekend/Holiday | - | 10 PM – 8 AM |
| Night Limit | - | 50 dBA residential |
| Code | - | SMMC Ch. 4.12 |
Highlighted rows indicate differences between cities.
Altadena FAQ
What are Altadena's quiet hours?
10 p.m. to 7 a.m. under LA County Code Ch. 12.08 — Altadena is unincorporated so LA County's noise ordinance applies.
How loud can my backyard be at night?
Single-family residential exterior noise is capped at 45 dBA from 10 p.m. to 7 a.m. per Section 12.08.390.
Santa Monica FAQ
What are the quiet hours in Santa Monica?
10 PM to 7 AM on weekdays and 10 PM to 8 AM on weekends and holidays. Residential noise must not exceed 50 dBA during these hours.
Can I play music in a park at night in Santa Monica?
No. Sound amplifying equipment and musical instruments are prohibited in City parks, beaches, and recreational facilities after 10 PM.
Compare other topics
See how Altadena and Santa Monica compare on other ordinance categories.
Want to add a third city?
Use our full comparison tool to compare up to three cities.
Open Comparison Tool