How does the ADU permit process work in Los Angeles specifically?

Los Angeles processes the highest volume of ADU permits in California, and the Los Angeles Department of Building and Safety (LADBS) has built dedicated programs and an electronic plan-review system to handle that demand. If you are building in the City of Los Angeles, knowing how those programs work — and where projects get stuck — can save weeks.

The ADU Standard Plan Program

LADBS maintains a library of pre-approved ADU standard plans that property owners may use, often at no cost for the architectural design itself. Using a pre-approved plan removes the architectural and structural review from the critical path because those elements were already vetted. What you still need, however, is a project-specific MEP set and a registered Title 24 CF1R tied to your exact parcel and climate zone — the standard plan does not include site-specific mechanical, electrical, and plumbing engineering or your energy compliance documents.

ePlanLA — electronic plan review

Los Angeles runs plan check through ePlanLA, its electronic submittal and review portal. Plans are uploaded as PDFs formatted for 24" x 36" sheets, reviewers mark up the set digitally, and corrections come back through the same system. This eliminates physical plan printing and courier trips, but it also means your PDFs must be properly formatted and your sheets clearly labeled (M-1, E-1, P-1, and so on) so the digital reviewer can navigate them. Our plans are delivered ready for ePlanLA and other California e-review portals.

A realistic timeline

For a custom ADU in Los Angeles that is not using a pre-approved plan, expect roughly 4 to 8 weeks for initial plan review in the 2025-2026 environment, plus additional time for each correction round and resubmittal. Pre-approved-plan projects move faster. The statutory decision deadlines still apply, but high application volume means well-prepared, correction-free submittals clear noticeably faster than the average.

Where LA projects commonly stall

• Electrical service capacity — LADWP service coordination is separate from the LADBS permit and can be a long pole, especially when a panel upgrade or new service is needed.
• All-electric requirements — Los Angeles has adopted reach-code provisions affecting gas in new construction; your mechanical and plumbing designs must reflect that.
• MEP corrections — missing load calculations, absent GFCI/AFCI notation, or DWV venting not shown are frequent correction items.
• Title 24 mismatches — the CF1R and the MEP equipment must agree, or the set comes back.

Practical advice for an LA ADU

1. Decide early whether a pre-approved standard plan fits your lot.
2. Open your LADWP service request as soon as you start the permit, not at the end.
3. Submit a complete ePlanLA package with coordinated MEP and a registered CF1R.
4. Respond to every ePlanLA correction comment specifically and completely to avoid extra rounds.

Los Angeles requirements and ordinances change frequently — confirm current LADBS and LADWP procedures before you file. Because we prepare California-specific, ePlanLA-ready drawings and include city corrections at no additional charge, ordering our Full MEP Package removes a major source of LA correction cycles. See how it works to get started.