ADU Permits: Mountain View vs Sunnyvale
How do adu permits rules compare between Mountain View, CA and Sunnyvale, CA?
Mountain View, CA
Santa Clara County
No data available yet for Mountain View.
Sunnyvale, CA
Santa Clara County
Sunnyvale processes ADU permits ministerially under Sunnyvale Municipal Code Title 19 (Zoning) and California Government Code 65852.2. Sunnyvale was one of the earliest California cities to adopt by-right ADU regulations (2017) and consistently rates as one of the most permissive Silicon Valley jurisdictions. State law requires action within 60 days of a complete application.
View full Sunnyvale rules →Key Facts Comparison
| Fact | Mountain View | Sunnyvale |
|---|---|---|
| Code Section | - | SMC Title 19 (Zoning) |
| Review Type | - | Ministerial (no hearing) |
| Decision Window | - | 60 days from complete app |
| Allowed Units | - | 1 ADU + 1 JADU per SFH lot |
| Early Adopter | - | 2017 by-right rules |
| Pre-Approved Plans | - | Available (AB 434) |
Highlighted rows indicate differences between cities.
Mountain View FAQ
No FAQs available.
Sunnyvale FAQ
How long does an ADU permit take in Sunnyvale?
California Government Code 65852.2(b)(1) requires Sunnyvale to act on a complete ADU application within 60 days. Sunnyvale's One Stop Permit Center is among the faster Silicon Valley processing offices - many simple ADUs reach permit issuance in 8-14 weeks including correction cycles.
Does Sunnyvale hold a public hearing on ADU permits?
No. SMC Title 19 follows California Government Code 65852.2 and makes ADU and JADU review strictly ministerial. The planner applies objective standards from the SFH zoning regulations - no public hearing, no neighbor notification, and no discretionary design review.
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