Two clocks run: the permit and the build. For a complete application, California requires a decision within 60 days, and as of November 2026 a completeness check within 15 business days. Design before that and construction after it take longer, and the lot, the plan and how fast corrections are answered decide the total.
Where does the time go?
- Lot check and design. Survey, layout, structural and energy work. Pre-approved plans can shorten this.
- Plan check. Submittal, completeness review, corrections and resubmittal.
- Utility work. Sewer, water and electrical capacity, sometimes with the utility on its own schedule.
- Construction and inspections. Foundation, framing, rough inspections, finishes, final.
What speeds things up?
- A complete first submittal, with the survey and utility routes worked out.
- A plan that already fits the setbacks and height limits.
- Quick answers to plan check comments.
- Ordering long-lead items like windows early.
Oakland notes
Plan on two reviews: Planning first, then Building. Pre-approved plans move faster through the building side. Lots in creek or fire overlays add steps.
Sources, as of November 2026: California Government Code section 66310 and following (ADU law), including SB 543 (2025); California Department of Housing and Community Development, ADU Handbook. General information, not legal advice. City of Oakland ADU pages.
Updated November 2026