Building an ADU usually involves plans, a permit application and inspections handled by your city or LA County. This section explains the general steps.
What this topic covers
The first question is who permits your lot. Inside the City of Los Angeles it is LADBS. Unincorporated areas use LA County Public Works and Planning, and other cities run their own departments. All follow the same state law, but forms, fees and portals differ.
Key facts
- LADBS says plan check, permit issuance and inspections are required for ADUs and JADUs.
- LADBS accepts ADU submittals through its ePlanLA portal.
- Under Gov. Code section 66317, the agency must act on a complete application within 60 days.
- LADBS says an application expires 18 months from the plan check submittal date.
- A pre-approved plan can speed plan review, but approval of a design is not approval of your lot.
Guides in this hub
- ADU permit process in Los Angeles: the eight steps, state deadlines, what an application needs and common mistakes.
- Prefab and pre-approved ADU plans: how the LADBS Standard Plan Program works and what prefab does and does not change.
The steps in short
In the City of Los Angeles the usual order is: check eligibility, get plans from a licensed professional, submit through ePlanLA, go through plan check and corrections, pay fees and get the permit, build with staged inspections, and finish with a final inspection and Certificate of Occupancy before anyone moves in.
Common mistakes
- Starting work before the permit is issued.
- Changing the design mid-build without telling the city.
- Paying a contractor for permits up front. CSLB says to confirm permit costs with your building department.
- Assuming a pre-approved plan removes site review.
Processes differ by jurisdiction. Confirm the current steps with your city or LA County.