LADBS ADU Submittal Checklist: Everything You Need to File (2026)

The complete document checklist for a City of LA ADU permit application — every plan, stamp, and form LADBS expects in your ePlanLA package. Get it right and the approval clock starts. Get it wrong and you wait. We'll show you the list, then match you with a vetted, licensed builder who assembles it for you.

We match you with vetted, California-licensed ADU builders in your area — no guesswork, no cold-calling contractors.

Almost every stalled ADU project in Los Angeles dies in the same place: an incomplete submittal. You file with LADBS, wait weeks, and instead of a plan-check review you get a list of what's missing — and the clock you thought was running never actually started. This page is the antidote: a complete, plain-English LADBS ADU submittal checklist covering every plan, stamp, and form your ADU permit application needs before it goes into ePlanLA, the city's online permitting portal.

One thing up front, because it shapes everything below: 1-800-ADU-Pros is a vetted directory and pre-qualification service, not a contractor. We don't draw plans, stamp drawings, or file permits — the independent, California-licensed builder you choose does all of that, and assembling this exact package is a core part of what they handle. Our job is to confirm your lot can support an ADU and match you to a pre-screened pro. Think of this checklist as a window into the work the right builder takes off your plate. For the full permitting walkthrough, start with our LA ADU permit guide.

The 30-second answer

A complete LADBS ADU submittal package includes: architectural plans (floor plans, elevations, sections), a site/plot plan showing setbacks and existing structures, structural plans with a licensed engineer's stamp, Title 24 / CF-1R energy compliance documents, grading & drainage details, MEP/utility details (water, sewer lateral, electrical service), and supporting docs (a ZIMAS printout or survey, the LADBS application forms, and owner authorization). Why it matters: under SB 543 (effective Jan 1, 2026) LADBS must make a completeness determination within 15 business days, and the 60-day SB 13 review clock only starts once your package is deemed complete. Completeness is the whole game.

What's on this page

1. Why completeness starts the clock
2. The full submittal checklist
3. Supporting documents & forms
4. Top reasons packages get rejected
5. Who assembles all this for you
6. Submittal FAQ

Why a complete package is the whole game

Two California statutes govern your ADU timeline. Only one of them starts when you hit "submit" — and it isn't the one you think.

Here's the sequence most homeowners don't understand until it costs them weeks. When you file an ADU permit application, LADBS first runs a completeness determination: a check of whether your package contains everything required to actually review it. Under SB 543, effective January 1, 2026, the city must make that call within 15 business days. If anything on the checklist below is missing, they deem the application incomplete and send it back with a list — and you start over.

The 60-day ministerial review window everyone quotes comes from SB 13. But that 60-day clock only starts once your application is deemed complete. An incomplete package is the single biggest reason that clock never starts — which means the fastest way to a permit isn't rushing the submission, it's submitting a package with zero gaps the first time.

The SB 543 completeness tip

Treat the 15-business-day completeness window as a pass/fail gate, not a review. LADBS isn't grading your design at this stage — they're only checking that every required item is present. A package that's 95% there still gets bounced. The leverage is brutal but simple: a fully complete first submission can save you a full correction cycle (often 4–6 weeks) versus a package that's one stamped sheet or one form short.

The full LADBS ADU submittal checklist

The seven core components of a complete ePlanLA package. Work top to bottom — each one is a separate deliverable, and a gap in any of them stops the clock.

1

Architectural plans — floor plans, elevations & sections

The heart of the set. Floor plans show room layout, dimensions, door/window locations, and square footage; elevations show each exterior face with heights and finishes; building sections cut through the structure to show wall assemblies, ceiling heights, and roof framing. These must be drawn to scale and reflect current City of LA code and ADU size limits.

Drawn to scale · all four elevations

2

Site / plot plan — setbacks, dimensions & existing structures

A scaled overhead drawing of your entire property: lot lines and dimensions, the existing house, the proposed ADU footprint, and every setback measured (4 ft side and rear for a detached ADU in LA). It must show driveways, existing structures, distances between buildings, and how the new unit complies with coverage and separation rules. Pull your lot data from ZIMAS to get the dimensions right.

Shows every setback & existing structure

3

Structural plans with a licensed engineer's stamp

Foundation plans, framing plans, and structural details — sized and stamped by a California-licensed civil or structural engineer (or architect of record). The wet/digital stamp is non-negotiable; LADBS will not deem a package complete without sealed structural sheets and the accompanying structural calculations. This is one of the most common items DIY filers leave out.

Engineer's stamp required

4

Title 24 / CF-1R energy compliance documents

California's Title 24 energy code applies to new ADUs. Your set needs an energy compliance report — for residential work this is typically the CF-1R (Certificate of Compliance) — documenting insulation values, fenestration (windows), HVAC, and lighting against the state standard. It's a discrete document that gets uploaded with the plan set, not something the plan checker infers from your drawings.

CF-1R uploaded with the set

5

Grading & drainage details

For detached units and sloped lots especially, LADBS wants to see how the site drains and whether any grading is involved — finished floor elevations, lot slope, drainage flow away from structures, and any retaining. On flat lots this can be light; on hillside or hazard-flagged parcels (which ZIMAS will reveal) it can be a substantial sub-set with its own review.

Heavier on hillside lots

6

MEP & utility details — water, sewer, electrical

Mechanical, electrical, and plumbing plans plus the utility connections that tie the ADU into your property: the water line, the sewer lateral connection (or septic, where applicable), and the electrical panel/service — including whether your existing panel has capacity or needs an upgrade. Utilities and sitework are the most under-budgeted part of an ADU at roughly 10–15% of total cost, so getting these details right early protects your budget as well as your timeline.

Panel capacity is a common gotcha

7

Supporting docs — survey/ZIMAS, application forms & owner authorization

The paperwork that frames the plans: a property survey or ZIMAS printout confirming zoning and lot data, the completed LADBS permit application forms, and owner authorization if anyone other than the owner (i.e., your builder or designer) is filing as applicant of record. Missing forms or an unsigned authorization will fail the completeness check just as fast as a missing plan sheet.

Don't skip the forms

This is a lot to assemble — and one gap restarts the clock.

The vetted builders in our network draw the plans, secure the engineer's stamp, run Title 24, and file a complete ePlanLA package for you. First, let's confirm your lot can even support an ADU.

A quick reference: every item, at a glance

The same checklist in table form — print it, or hand it to whoever's pulling your package together.

A few notes that save headaches. Keeping your ADU under 750 sq ft exempts it from impact fees by state law (CA HCD), which is worth weighing while your plans are still on the table. And if speed is the priority, a LADBS pre-approved standard plan ships with much of this set already reviewed — shrinking both the package you assemble and the time in plan check. For the bigger picture on why the statutory timelines rarely match reality, see the 60-day approval law vs. reality.

Why submittal packages get kicked back

If LADBS deems your application incomplete, it's almost always one of these. Each one means starting the 15-day clock over.

• No engineer's stamp on the structural sheets. The single most common DIY miss. Sealed structural plans and calcs are mandatory — an unstamped set is incomplete by definition.
• Title 24 / CF-1R missing entirely. Filers often assume the drawings cover energy compliance. They don't — the CF-1R is its own uploaded document.
• Site plan doesn't show measured setbacks. A plot plan without dimensioned setbacks and existing structures can't be reviewed against LA's 4 ft detached rule.
• Incomplete or unsigned application forms. An owner authorization left blank when a builder files as applicant will fail the check.
• Utility/MEP details left out. No sewer lateral connection or electrical service shown means the plan checker can't confirm the unit is serviceable.
• Plans not to scale or missing sheets. Elevations for only two faces, or floor plans with no dimensions, get bounced fast.

The pattern is clear: completeness failures are rarely about design quality — they're about assembly. Every item is present and properly stamped, or it isn't. That's exactly the kind of disciplined package an experienced LA ADU builder produces routinely, because they've cleared the LADBS completeness gate dozens of times. Unsure which rules apply to your specific lot before any of this gets drawn? That's what the free qualification check below is for.

Want a complete package filed right the first time?

We'll check your address, zoning, lot size, and setbacks for free and tell you straight whether an ADU pencils — then connect you with a vetted LA builder who assembles and files the full ePlanLA submittal for you.

You don't have to assemble this package alone

The most common regret we hear: "I thought I'd just upload some plans — I had no idea it was this many separate, stamped documents." Here's the alternative.

1-800-ADU-Pros is a vetted directory of California-licensed LA ADU builders. We're not a contractor and we don't hold a license, and we don't pull permits — the independent builders we match you with do all of that, and each one's CSLB license number is shown on their profile. The builder you choose runs ZIMAS, draws the architectural set, coordinates the engineer's stamp and Title 24, prepares the grading and MEP details, completes the forms, and files the complete package through ePlanLA as the applicant of record. The submittal headache this page just walked you through is, start to finish, their job — not yours. Here's the two-step path to get there:

1. Step 1 — Free property qualification (remote). Enter your address. We assess zoning, lot size, setbacks, and overlays and tell you straight whether your property likely qualifies. No cost, no commitment.
2. Step 2 — Free on-site feasibility assessment. If it looks viable, a vetted, licensed builder visits to check electrical/panel capacity, water and sewer access, and layout — the diligence that informs the utility and structural details in your submittal before a single sheet is drawn.

From there, the builder handles the full submittal, the plan-check corrections, and inspections through your Certificate of Occupancy — design, permit, and build under one roof. New to the permitting process entirely? Start with our LA ADU permit guide, or if you already have an unpermitted unit, see how to legalize it.

LADBS submittal questions, answered

The questions LA homeowners ask most before they file.

What documents do I need for a complete LADBS ADU submittal?

A complete package includes architectural plans (floor plans, elevations, sections), a site/plot plan showing setbacks and existing structures, structural plans with a licensed engineer's stamp, Title 24 / CF-1R energy compliance documents, grading and drainage details, MEP/utility details (water, sewer lateral, electrical service), and supporting docs — a ZIMAS printout or survey, the LADBS application forms, and owner authorization. Missing any one of these can fail the completeness check.

Why does completeness matter for the ADU approval clock?

Under SB 543, effective January 1, 2026, LADBS must determine whether your application is complete within 15 business days. The separate 60-day SB 13 review clock only starts once your package is deemed complete. An incomplete submittal is the number-one reason that 60-day clock never starts — so a complete package is the fastest path to a permit.

Do ADU structural plans need an engineer's stamp?

Yes. Foundation and framing plans must be sized and stamped by a California-licensed civil or structural engineer (or the architect of record), along with the supporting structural calculations. LADBS will not deem a package complete without sealed structural sheets. Missing the stamp is one of the most common reasons DIY submittals get rejected.

What is Title 24 / CF-1R and is it required for an ADU?

Title 24 is California's building energy efficiency standard, and it applies to new ADUs. For residential work the compliance document is typically the CF-1R, a Certificate of Compliance documenting insulation, windows, HVAC, and lighting against the state code. It is a separate document uploaded with your plan set, not something inferred from the drawings, and a complete submittal requires it.

How do I file an ADU permit application with LADBS?

City of Los Angeles ADU permit applications are filed electronically through ePlanLA, the LADBS online portal. You upload the full plan set and supporting documents, pay initial plan-check fees, and the application enters the completeness review queue. A licensed builder or designer normally files as the applicant of record on the owner's behalf.

Does 1-800-ADU-Pros prepare or file the submittal package?

No. 1-800-ADU-Pros is a referral and pre-qualification service, not a licensed contractor. We confirm whether your property qualifies and match you with a vetted, California-licensed CSLB builder. That independent builder draws the plans, secures the engineer's stamp and Title 24, assembles the package, files it through ePlanLA, and pulls the permit. Their license number is listed on their profile.