ADU Rules: Palo Alto vs Sunnyvale
How do adu rules rules compare between Palo Alto, CA and Sunnyvale, CA?
Palo Alto and Sunnyvale have similar restriction levels.
Palo Alto, CA
Santa Clara County
Palo Alto regulates ADUs and JADUs under Palo Alto Municipal Code §18.42.040 (with updated provisions in PAMC Chapter 18.09). Attached ADUs are capped at 850 sq ft for studio/one-bedroom or 1,000 sq ft for two-or-more bedrooms, and may not exceed 50% of the primary dwelling. JADUs are limited to 500 sq ft within the existing single-family dwelling.
View full Palo Alto rules →Sunnyvale, CA
Santa Clara County
Sunnyvale allows ADUs and JADUs on single-family and multifamily lots under California Government Code 65852.2 plus AB 68, 881, and SB 13. AB 1033 now allows ADUs to be sold as separate condos.
View full Sunnyvale rules →Key Facts Comparison
| Fact | Palo Alto | Sunnyvale |
|---|---|---|
| Code Section | PAMC 18.42.040 (Ch. 18.09) | - |
| Max Attached (studio/1 BR) | 850 sq ft | - |
| Max Attached (2+ BR) | 1,000 sq ft | - |
| Height (Eichler Tract) | 16 ft (vs 17 ft standard) | - |
| STR Use | Prohibited by deed restriction | - |
| State law | - | Gov Code 65852.2 plus AB 68, 881, SB 13 |
| Max detached ADU | - | 1200 square feet |
| JADU size | - | Up to 500 square feet |
| Setbacks | - | 4 feet side and rear |
| AB 1033 | - | Condo sale if city opts in |
Highlighted rows indicate differences between cities.
Palo Alto FAQ
How big can my Palo Alto attached ADU be?
Per PAMC 18.42.040, attached ADUs are capped at 850 sq ft for a studio or one-bedroom unit and 1,000 sq ft for two-or-more bedrooms, and may not exceed 50% of the primary dwelling.
Why is the height limit lower for Eichler Tract ADUs?
PAMC 18.42.040 reduces the one-story ADU height limit to 16 feet in Eichler Tracts (vs 17 feet citywide) to maintain compatibility with the slab-on-grade mid-century architecture identified in the Eichler Neighborhood Design Guidelines.
Can I rent my Palo Alto ADU on Airbnb?
No. PAMC 18.42.040 requires a recorded deed restriction prohibiting short-term rental of the ADU. Rentals must be for terms of 30 days or longer.
Sunnyvale FAQ
Do I need extra parking for my Sunnyvale ADU?
No additional parking is required if your property is within a half mile of public transit, which covers most of Sunnyvale.
Can I sell my ADU as a separate condo?
Only if Sunnyvale has opted into AB 1033. Check with the Planning Division for current local policy.
Compare other topics
See how Palo Alto and Sunnyvale 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