| Table of Contents |
| 1. What is an ADU? |
2. Benefits of Building a Permitted ADU |
| 3. How Long Does It Take to Get an ADU Permit in California? |
| 4. 5 Key Stages in the ADU Permit Process |
| 5. What Can Delay an ADU Permit? |
| 6. Tips to Speed Up the ADU Permit Process |
| 7. FAQ |
What is an ADU?
An Accessory Dwelling Unit (ADU) is a secondary residential structure built on the same lot as a primary residence. Commonly referred to as secondary suites, granny flats, in-law units, or backyard homes, ADUs can be detached, attached, or converted from existing spaces like garages or basements.
In California, ADUs are a key part of solving the housing crisis. State laws have streamlined the approval process, but actual permit timelines can still vary depending on location, property type, and city regulations.
✅ Benefits of Building a Permitted ADU
- Building a permitted ADU isn't just a legal requirement—it’s a smart investment. Here’s why:
Increase in Property Value – A legal ADU adds resale value and long-term equity.
Rental Income – Generate passive income with a long-term or mid-term rental.
Family Flexibility – Ideal for multigenerational living or a home office.
Legal Compliance – Avoid code violations, fines, and costly teardown notices.
Access to Financing – Lenders favor permitted ADUs for refinancing and home equity loans.
⏳ How Long Does It Take to Get an ADU Permit in California?
Under California state law (AB 68), local jurisdictions are required to approve or deny a complete ADU permit application within 60 days. However, the actual timeline depends on several factors:
🔄 Average Permit Timelines (2024–2025)
| City | Average Time to Permit Approval |
|---|---|
| Los Angeles | 2–4 months |
| San Diego | 2–3 months |
| San Francisco | 4–6 months |
| Oakland | 3–5 months |
| San Jose | 2–4 months (with fast-track options) |
| Sacramento | 2–3 months |
| Smaller cities | 2–6 months depending on resources |
Feasibility Review (1–2 weeks)
Assess zoning, setbacks, and lot conditions.
Design & Planning (2–6 weeks)
Create architectural drawings, energy calculations, and engineering plans.
Submit Permit Application
Turn in all required documents to the city building department.
City Review & Revisions (Up to 60 Days)
The city may request plan revisions before approval.
Permit Issuance & Construction Start
Once approved, construction can begin immediately.
⚠️ What Can Delay an ADU Permit?
Despite the 60-day mandate, the clock only starts once the application is complete. Common causes of delay include:
Incomplete or incorrect submittals
Missing structural calculations or Title 24 compliance
Historical district overlays or environmental restrictions
Poor communication with the planning department
Changes to plans during review
🧩 Tips to Speed Up the ADU Permit Process
✅ Use pre-approved ADU plans if available (e.g., San Jose, LA)
✅ Consult your city’s Planning Department before submitting
✅ Be proactive with plan corrections
✅ Bundle your applications (Planning + Building)
