Los Angeles Pre-Approved ADU Standard Plans, Explained

Written by Dekel Sofer · Last reviewed 25 September 2026

Los Angeles pre-approved ADU standard plans are designs LADBS has already checked against the building code, so structural plan review is largely done before you apply. The city lists each plan with the architect who owns it; using one cuts design time and plan-check cost compared with custom plans.

The City of Los Angeles keeps a catalog of ADU designs that have already been checked against the building code. Build from one and the structural review is largely done before you apply. It is the closest thing to a shortcut that exists in LA permitting, and most homeowners have never heard of it.

It is also widely misdescribed. Below is what the program actually is, taken from LADBS itself, including the parts that are easy to get wrong.

What a standard plan actually is

A standard plan is a complete ADU design, owned by a private architect or design firm, that LADBS has already reviewed for compliance with the Building, Residential and Green Codes. Because that review has happened once, it does not have to happen again for every homeowner who builds it. LADBS puts it plainly: using a standard plan “greatly reduces the time required for plan check. Permits can therefore be issued much faster.”

What it is not is a permit. And LADBS is careful to add that pre-approval “is not an endorsement” of the designer’s credentials or the quality of their work — the City has checked the drawings, not the firm.

Why the program exists, and why Los Angeles was four years early

LADBS launched the ADU Standard Plan Program on 5 March 2021. At the time nothing obliged the City to do it. That changed with AB 1332, which added Government Code section 65852.27 and required every city and county in California to have a pre-approved ADU plan program in place by 1 January 2025. Los Angeles had one running almost four years before the deadline, which is why its catalog is deeper than most and why several neighboring cities now cross-reference LA-approved designs rather than build a library from scratch.

The statute matters for a second reason, and it is the one homeowners actually feel. Section 65852.27 requires a local agency to approve or deny a permit application for a detached ADU that uses an already pre-approved plan within 30 days of receiving a complete application, and to decide requests to pre-approve a plan under the state ADU standards. That 30-day clock is a state-law deadline on the permit application, not a promise that your ADU is permitted 30 days after you decide to build one. It starts when a complete application lands, and corrections restart the conversation. But it is the only defensible number anyone can quote you about this program, and it comes from the Government Code rather than from a contractor’s memory.

There is one plan the City gives away free

Almost every plan in the catalog is privately owned, and you buy it from the designer. One is not. YOU-ADU is owned by the City of Los Angeles, and LADBS states that it “may be used by property owners free of charge.”

• Designed by Michael Lehrer FAIA of Lehrer Architects and Nerin Kadribegovic AIA of Kadre Architects.
• Single story, one bedroom, 455 square feet as listed by LADBS. Worth knowing: the plan set’s own cover sheet says 445 sq ft. A ten-foot discrepancy between the catalog and the drawings is the kind of thing that matters at plan check, so confirm the figure against the current set before you design around it.
• Choices built into the set: asphalt shingle or standing-seam metal roof, stucco or fiber-cement siding, optional partition casework and trellis, and a choice of paint and frame colors.
• What “free” covers: the plan set itself, as a downloadable PDF. It does not waive plan check or permit fees, which are still calculated on project valuation, and it does not remove the site-specific work described below.
• One construction condition to plan around: if the ADU sits less than three feet from an adjacent structure, the set requires one-hour fire-rated exterior walls and protected openings. The set also flags methane mitigation and grading inspection as site-specific plan-check items.

For a homeowner who wants a compact one-bedroom unit and does not need a custom layout, this is the cheapest legitimate route into an ADU that exists in Los Angeles.

What YOU-ADU assumes about your lot

A free plan is only free if it fits. The YOU-ADU drawings are engineered against a specific set of site assumptions, printed on the set itself, and a lot that misses any of them needs site-specific engineering that the free plan does not include.

None of this makes YOU-ADU a bad plan. It makes it a flat-lot plan. On a level San Fernando Valley or Eastside lot with ordinary soil it is genuinely the cheapest legitimate route into an ADU in the city. On a hillside parcel in the Santa Monica Mountains it is a design you will pay an engineer to substantially rebuild, at which point a custom ADU is usually the cleaner decision.

What is in the catalog

• 55 approved plans when we counted the catalog on 1 November 2026, numbered ADU1 through ADU96 plus YOU-ADU, alongside 31 marked Expired and 2 marked Pending Approval.
• Sizes from 200 to 1,200 square feet — the smallest is ADU12, the largest are ADU8 and ADU45.
• Studio through three-bedroom, with roughly nine two-story designs for lots where footprint is tight.
• Two plans are still pending approval — ADU55 and ADU56.
• The designers are not obscure. The list includes Abodu, Connect Homes, Cover, Villa Homes, United Dwelling, Plús Hús, LA-Más, SO-IL, Escher GuneWardena, Fung + Blatt Architects, wHY, Design Bitches, Welcome Projects and Tom Marble Architecture, among others.

The trap: expired plans sit in the same table

This is the single most useful thing to know before you browse the list. Roughly thirty of the plans in the catalog are expired — mostly the low-numbered early ones — and they are not moved to a separate page or grayed out. They sit in the same table as the live ones, distinguished only by a status column that is easy to scroll past.

Fall in love with an expired design and you have lost the entire benefit of the program. Check the status column on every plan before you contact anyone about it.

Expiry is not a filing technicality, and it is the part almost nobody explains. The 30-day deadline in Government Code section 65852.27(b) only attaches to an application that uses a plan the City preapproved within the current triennial California Building Standards Code rulemaking cycle — or a plan identical to one used in a detached-ADU application the City approved within that same cycle. California adopts a new edition of its building standards every three years, and a plan approved under the previous edition falls outside that window. That is what the Expired status in the catalog is actually telling you.

So an expired plan does not just mean out-of-date drawings. It means the one enforceable promise the program carries, a decision in 30 days, no longer applies to your application at all. You are back to an ordinary ADU submittal, with the plan purchase already paid for.

Who owns these plans, and how you contact the firm

With one exception you buy the plan from the firm that designed it, not from the City, and state law requires the City to publish that firm’s contact details next to the plan.

The catalog lists every plan with six columns — Img, Plan No., Category, Plan Description, Firm Name and Status. Size is not a column of its own; it is written into the plan description, as in (455 sf). The Firm Name column is the one most people scroll past, and it is the one that tells you who you will actually be dealing with.

Government Code section 65852.27(a)(4)(B) requires the City to post the contact information of whoever submitted each preapproved plan, as that applicant provided it, and says in the same breath that the City shall not be responsible for the accuracy of it. Section 65852.27(a)(4)(A)(ii) adds that posting a plan shall not be considered an endorsement of the applicant. Read those two together and the City’s position is clear: it has checked the drawings, not the firm, and not even the phone number. Verify the firm’s license status and credentials and its current contact details yourself before you send anyone money.

A plan can also disappear from the list. Section 65852.27(a)(4)(C) requires the City to remove a preapproved plan within 30 days of the plan owner asking for it to come down. That is a different 30-day clock from the permit deadline, and it matters if you are working from a screenshot taken a few months ago.

The firms in the catalog range from small architecture studios to factory-built-unit suppliers. These were the plan owners listed when we counted the catalog on 1 November 2026:

• City of Los Angeles
• Welcome Projects
• Jennifer Bonner/MALL
• Abodu
• First Office
• Fung + Blatt Architects
• IT House
• Connect Homes
• Design, Bitches
• Amunátegui Valdés
• Escher Gunewardena Architecture
• wHY
• LA Más
• SO – IL
• sekou cooke STUDIO
• United Dwelling
• YD Group
• URD
• Cottage
• Complete Package Drafting
• Villa Homes
• Plús Hús
• Lytemods
• neXt Dwelling
• SonderPods
• Tom Marble Architecture (TMA)
• Modal
• ERW Design
• Infinity Concept Inc.
• Bright Space LLC
• Mei Li Homes LLC
• Cover
• HOMEIO
• Buildoly
• Swift Lee Office
• Patrick Moore / Moore Land Co. LLC
• ARA-la Studio
• ADU Garage Designs
• Butterfly Dwellings, Inc.
• Castleblock, Inc.

Several of those names — Abodu, Connect Homes, Cover, Villa Homes and Plús Hús among them — deliver as factory-built units rather than framing on site, which changes the build sequence, the site access you need and the payment structure more than it changes the drawings. If that is the direction you are leaning, prefab versus site-built ADU construction is the comparison to read first.

What a standard plan removes — and what it does not

• Already checked: the structure’s compliance with the Building, Residential and Green Codes.
• Still yours to submit: everything specific to your property. LADBS requires site-specific information “including compliance with the Zoning Code and foundation requirements” — your setbacks, your soil, your lot.
• Still a final review: LADBS states that “all pre-approved standard plans require final review by LADBS, to ensure final compliance and address site-specific conditions.” Nobody skips plan check entirely.
• Roof decks: for plans approved with them, LADBS notes the decks “may require additional setbacks in specific zones.”

How you actually use one

1. Review the catalog and pick candidates — checking the status column as you go.
2. Contact the plan owner. Except for YOU-ADU, these are privately owned designs. LADBS: “property owners interested in building a structure with a Standard Plan must contact the owner of the plan to purchase a copy.” Each designer sets their own price, and LADBS does not publish them.
3. Work with that designer to fit the plan to your property. LADBS notes that “pre-approved designs may or may not be able to be customized” — ask before you pay.
4. Optionally run the drawings through the City’s AI pre-plan check tool.
5. Submit through ePlan LA.
6. Obtain the permit.
7. Build, with inspections.

What LADBS does not promise

You will see specific claims made about this program — that it saves a fixed number of weeks, or reduces your fees. LADBS states neither. It says plan check time is greatly reduced and permits issue much faster, and it puts no number on it. Permit fees are based on project valuation whether the plan is pre-approved or custom.

The saving is real. The precise figure is not something anyone can promise you honestly, and a contractor quoting one is quoting their own experience rather than City policy.

When a standard plan is the wrong route

LADBS notes that these plans “may not be approved for use in certain situations and/or site conditions.” In practice the ones that most often rule it out are a steep or hillside lot that needs a stepped or shored foundation, a footprint the catalog simply does not offer, a garage you would rather convert than replace, and any site where access or utilities force a different layout. In those cases a custom ADU design from an ADU builder in Los Angeles is the faster route, not the slower one.

One requirement no plan removes: solar

A new detached ADU built from scratch in Los Angeles is treated as a newly constructed dwelling for energy-code purposes, which means it needs a photovoltaic system. Choosing a pre-approved plan does not change that, and the catalog listing will not remind you. Budget for it as part of the project rather than discovering it at plan check.

This is one of the practical reasons a garage conversion sometimes beats new detached construction on cost even when the finished square footage is similar — a conversion of an existing structure is a different animal under the energy code. We walk through that trade in detail in detached ADU vs garage conversion.

Standard plan, custom design or garage conversion

Most homeowners weighing a standard plan are really choosing between three routes. They are not ranked; they suit different lots.

If the question is really whether an ADU is the right addition at all, ADU vs room addition compares it against extending the main house, and room additions covers that route.

If your property is in unincorporated Los Angeles County

The County runs its own pre-approved plan program with three free plans of its own, and it is a different agency with a different submittal from the City’s. A Los Angeles mailing address does not tell you which of the two you are in.

This catches people out constantly. Large unincorporated pockets across the county carry Los Angeles postal addresses but sit outside the City of Los Angeles, so LADBS is not the building department and the LADBS catalog is not open to them. The County publishes three County-owned plans that homeowners may use free of charge:

The County says additional plans designed and owned by local design firms will be made available in the future. Those will work the way the City’s do — bought directly from the plan owner rather than free.

The route through the County is its own sequence. You download the free County plan or buy a firm’s package, then submit a Regional Planning base application with a completed site-specific plot plan template for review and approval. With the approved plot plan set in hand you file a residential new-construction building permit application, either at a Building and Safety district office or online through EPIC-LA, which the County limits to unincorporated areas, uploading the complete plan package and site-specific Title 24 energy calculations and paying any plan check fees. The plan check engineer then gives you an agency referral sheet listing the County, state, federal or other agencies whose approval you need before a permit can issue. Plans are checked and approved, you submit those agency approvals, you pay the permit fees through EPIC-LA, and the building official issues the permit.

Two County rules are worth knowing before you fall for a layout. The plans cannot be revised and must be permitted as designed — the County states that any changes are not allowed — although the unit may be oriented in any direction and the floor plan may be mirrored. And the County warns, as the City does, that a pre-approved standard plan may not be approved for use in certain situations or site conditions, so the plot plan review is where you find out whether your lot works.

Once the permit issues, keep it alive. The County requires the permit holder to request an inspection within 12 months of issuance to avoid the permit expiring, and a follow-up inspection every 180 days after that. Inspections are requested online through the Request Inspection menu in EPIC-LA.

The County publishes no fee schedule and no processing timeline for this program — only that plan check fees and permit fees apply. Anyone quoting you a County figure for either is guessing. If you are not certain which jurisdiction your parcel sits in, that is the first thing to settle, and we check it as a matter of course before any design work starts.

Pre-approved plan programs near Los Angeles

The LADBS catalog only applies inside the City of Los Angeles. If your address is in an unincorporated pocket or a neighboring city, you are looking at a different program — and because of AB 1332 every one of them now has to have something. They vary enormously in depth.

These programs change more often than city websites suggest. Verify the current catalog with the jurisdiction before you pay a designer. Our city-by-city ADU rules guides cover the zoning side of the same question, and we build across Los Angeles, Orange, Ventura, western Riverside and western San Bernardino counties — including Beverly Hills, Glendale and Pasadena.

What it changes about cost, and what it does not

A pre-approved plan is a design and permitting shortcut. It is not a construction discount. The three cost buckets behave differently:

• Design fees — this is where you save. You buy a finished drawing set instead of commissioning one, or take YOU-ADU for nothing. This is the real financial benefit of the program.
• Permit and plan-check fees — unchanged. LADBS calculates these on project valuation regardless of which route you take. Our LADBS permit cost guide explains how that valuation is arrived at.
• Construction — unchanged. A 600 square foot ADU costs what a 600 square foot ADU costs. Foundations, framing, a full kitchen and bath, a new electrical panel and a solar system do not get cheaper because a plan was pre-reviewed.

For where the money actually goes, see our pricing guide and junior ADU costs in Los Angeles. If the gap between what you want and what you can fund is the real problem, ADU financing options covers the routes we see homeowners actually use.

Sources

ADU law changes most years and local ordinances are amended separately from the state statute. The rules referenced above were checked against the current state sources on the date shown; confirm anything decision-critical with LADBS or your city for your specific lot.

• California Department of Housing and Community Development, Housing Law Fact Sheets — Accessory Dwelling Units (April 2026) — confirms that ADU law sits at Government Code sections 66310–66342, the four-foot side and rear setback limit for new detached ADUs, the 60-day decision deadline, and that impact fees may not be charged on an ADU of 750 square feet or less or on a JADU (Government Code section 66311.5, formerly 66324).
• California HCD, Accessory Dwelling Unit Handbook (March 2026) — Government Code section 66321(b)(3) bars a city from applying lot coverage, floor area ratio, open space or minimum lot size standards that would not permit at least an 800 square foot ADU with four-foot side and rear setbacks, at a height of up to 16 feet.
• California Government Code section 65852.27 — read in full on the official California Legislative Information site: the duty to run a preapproval program, the requirement that the City post the plan applicant’s contact information and is not responsible for its accuracy, the 30-day removal rule in subdivision (a)(4)(C), and the 30-day permit deadline in subdivision (b) with its condition that the plan have been preapproved within the current triennial California Building Standards Code rulemaking cycle. As amended by Stats. 2024, Ch. 7, Sec. 17 (SB 477), effective 25 March 2024.
• LADBS approved ADU standard plans catalog — plan numbers, categories, plan descriptions, firm names and current statuses. Counted on 1 November 2026: 55 Approved, 31 Expired, 2 Pending Approval. Statuses change, so confirm any plan before relying on it.
• Los Angeles County Department of Public Works, Pre-Approved ADU Standard Plans Program — the three County-owned plans and their sizes, the submittal sequence through Regional Planning and EPIC-LA, the no-revisions rule, and the 12-month and 180-day inspection requirements. The County publishes no fee amounts or processing timeline for the program.

Last reviewed 1 November 2026.

Questions we get asked about standard plans

Does a pre-approved plan mean I skip plan check?

No. LADBS is explicit that every pre-approved standard plan still requires final review to confirm compliance and address site-specific conditions. What has already been reviewed is the structure. What you still submit is your property: zoning compliance, setbacks, foundation, and any overlay that applies to your parcel.

How much faster is it, really?

LADBS says plan check time is greatly reduced and puts no number on it. State law does put a number on one step: Government Code section 65852.27 requires ministerial approval of a permit application using a pre-approved plan within 30 days of a complete submittal. Anything beyond that — “four to six weeks down to a day” and similar — is somebody’s anecdote, sometimes a five-year-old press quote, not current City policy.

Can I change the layout of a standard plan?

Sometimes. LADBS states that pre-approved designs “may or may not be able to be customized,” and the answer belongs to the firm that owns the plan. Ask before you buy. Material changes can also push the set back into review, which erodes the reason you chose it.

Is YOU-ADU really free?

The drawing set is. LADBS states it may be used by property owners free of charge. Plan check and permit fees, the site-specific engineering your lot needs, and the construction itself are not.

Does a standard plan work on a hillside lot?

Usually not without new structural engineering. YOU-ADU is designed for level grade, and most privately owned plans in the catalog carry similar assumptions. On a sloped or hillside parcel the foundation is the expensive part of the design, and it is exactly the part a catalog plan cannot supply.

How long does the whole project take?

Permitting is one phase of several. How long does an ADU take walks through design, permitting, construction and inspection as a single timeline, which is the number most homeowners are actually asking for.

Does using a standard plan change what my lot allows?

No. Size limits, height, setbacks and parking come from state law and the City’s ordinance, not from the plan you pick. Check yours with the California ADU rules calculator first, then shop the catalog for a design that fits inside the answer.

Who do I contact about a LADBS pre-approved plan?

The firm named in the Firm Name column of the catalog, not LADBS. State law requires the City to post the plan applicant’s contact information alongside each preapproved plan, and expressly says the City is not responsible for whether that information is accurate and that listing a plan is not an endorsement of the firm. So treat the catalog as a directory rather than a referral: confirm the firm is currently reachable, check its CSLB license, and confirm the plan’s status still reads Approved before you buy anything.

Where we fit

We will walk your lot and tell you whether a standard plan works on it — and which ones — before you pay a designer anything. If one fits, we will say so, including when the free City plan is the sensible answer. If your site rules them out, we will tell you that too, and why. Either way you get it in writing after the first visit. Costs, the permit path and what we check on a Los Angeles lot are on our City of Los Angeles ADU permit and cost page.

Before you choose a plan: check what your lot allows with our California ADU rules calculator — size, height, setbacks, parking and fees, with the statute behind each answer. The City of Los Angeles adds its own ordinance on top of the state floor; our Los Angeles ADU rules guide walks through both.

Sources: LADBS ADU Standard Plan Program and the official list of approved standard plans at dbs.lacity.gov/adu/approved-standard-plans, plus the published YOU-ADU plan set. Plan counts and statuses change as designs are added, renewed and expired — confirm the current status of any plan on the LADBS list before making decisions. Statutory deadlines are from California Government Code section 65852.27, added by AB 1332 (2023). Neighboring-city program details are from each jurisdiction and change frequently.