Los Angeles ADU Regulations

TL;DR: Los Angeles ADU Regulations

An accessory dwelling unit is an independent home on the same parcel as a primary residence. It needs permanent living, sleeping, cooking and sanitation facilities. In Los Angeles, the first design decision is which approval pathway fits your property: a new detached building, an attached addition, a conversion, a junior ADU or a qualifying multifamily project.

California’s ADU law protects certain sizes, heights, setbacks and approval procedures. Those protections do not make every floor plan suitable for every lot. Existing buildings, fire safety, utilities, easements, topography and the property’s jurisdiction still matter. A useful feasibility review puts the rules on a measured site plan before choosing finishes or assuming a construction price.

• Check the jurisdiction first. City of Los Angeles rules are different from the application process for unincorporated areas, Diamond Bar or other incorporated cities.
• Four-foot side and rear setbacks are an important starting point for new ADUs. Qualifying conversions and same-location replacements have different setback protections.
• An eligible 800 sq ft ADU has strong state protections. The 850 and 1,000 sq ft figures are protections against restrictive local size caps, not universal maximums.
• A JADU is limited to 500 sq ft. Its kitchen, bathroom, ownership and location requirements differ from an ordinary ADU.
• Parking is often exempt, but the reason matters. Transit access, conversion status and other statutory conditions need to be checked for the actual proposal.
• The 60-day review period starts with a complete application. It is not a promise that design, utility upgrades and construction will finish in two months.
• Under the 2026 fee provision, an ADU of 750 sq ft or less is exempt from impact fees. This does not eliminate every permit, utility or school-related charge.

This guide distinguishes state protections from project-specific decisions. It is dated November 6, 2026; confirm the rules applicable to your submission before relying on a dimension or deadline. Source links throughout the guide identify the relevant statutes and city agencies.

Essential ADU rules for Los Angeles

What you can build

Read these rules together with Government Code 66314, 66321, 66323 and 66333.

The three numbers homeowners often confuse

750 sq ft concerns an impact-fee exemption in the 2026 statute. 800 sq ft appears in important development-standard protections and the state-exempt detached pathway. 1,200 sq ft is a detached-unit limit in the general state ordinance framework. These numbers answer different questions. A design should not be reduced or enlarged simply because one number appears on an online checklist.

For example, a homeowner comparing a 750 sq ft unit with an 800 sq ft unit should assess the extra usable space, the fee treatment and the applicable approval route separately. Neither size guarantees a low construction cost. A shorter utility run, a straightforward foundation and a workable access route can matter as much as a small difference in floor area.

Confirm your city and property jurisdiction

A postal address is not a planning determination. The wider Los Angeles region includes the City of Los Angeles, other incorporated cities and unincorporated communities. Their departments, zoning records and local review procedures are not interchangeable. This page concerns the City of Los Angeles, including its neighborhoods, rather than every address in the surrounding region.

Start with the exact property address and assessor’s parcel number. Use Los Angeles City Planning’s zoning search to reach ZIMAS and inspect the parcel. Review zoning, planning notes, applicable overlays and the recorded property information. Then compare those records with existing permits and what is physically on the site.

What if my home is in Diamond Bar, Pomona or another nearby city?⌄

Use the reviewing agency for that city. For Diamond Bar, see the Diamond Bar ADU regulation guide. Uni Construction’s office locations do not change a property’s permitting jurisdiction. A Diamond Bar project should not be submitted using a City of Los Angeles checklist just because the property is near Los Angeles. Each municipality has its own reviewing agency and application process.

For a parcel outside an incorporated city, start with the responsible planning department’s ADU guidance. If the address search is unclear, resolve the boundary question before paying for a full design. Keep the jurisdiction confirmation with your project records so every consultant uses the same assumptions.

What should I collect before a feasibility review?⌄

Bring the address, parcel information, any available survey, previous plans and permits, and photographs of the house, garage, yard and access route. Identify known easements, slopes, retaining walls and utility equipment. Explain whether the ADU is intended for family, rental housing or a future change in living arrangements.

A sketch can communicate your goals, but it should not replace measured information. The difference between a fence and a legal property line can change the footprint. Existing drawings may also omit later alterations. Resolving those uncertainties early is more useful than producing a polished layout that must be redrawn.

How many ADUs can you build?

The answer depends on the existing residential configuration and the statutory pathway. A single-family lot and an existing multifamily property do not have the same unit-count rules. California Government Code 66323 provides specific approval categories and allows qualifying combinations. That is why a blanket statement such as “one ADU per property” can be misleading.

What can qualify on a single-family lot?⌄

Section 66323 includes a conversion ADU and a JADU within qualifying proposed or existing residential space, or qualifying existing accessory space for the ADU. It also provides a new detached ADU pathway that a local agency may limit to 800 sq ft. The statute permits qualifying categories to be combined; each proposed unit must satisfy the conditions of its own category.

This does not mean every small lot can physically accommodate every possible combination. Identify the primary dwelling, existing accessory structures and any existing ADU or JADU. Then draw the proposed configuration and check independent access, building safety and services. Ask the reviewing agency to confirm the unit-count basis for the actual site rather than relying on an unlabeled diagram.

What changes for an existing multifamily property?⌄

Qualifying nonlivable portions of an existing multifamily structure can be converted into ADUs under section 66323. The statute requires at least one such conversion allowance and allows up to 25 percent of the existing multifamily dwelling units, subject to the pathway’s conditions. Examples of potentially eligible spaces include storage areas or garages; occupied living space is a different question.

The detached pathway for an existing multifamily site allows up to eight detached ADUs, but no more than the number of existing units on the lot. For a lot with a proposed multifamily dwelling, the corresponding detached allowance is up to two. These are different categories, so do not apply the eight-unit figure to every property described casually as a duplex or apartment site.

Before estimating rental income from several new units, establish the legal number and type of existing dwellings. A converted room, an assessor entry and a permitted dwelling are not automatically equivalent evidence. The design team should document the proposed pathway for each new unit and resolve any uncertainty with the city.

Source: Government Code 66323, state-exempt ADU categories and combinations.

ADU size, height and design limits

How large can the ADU be?

The general state framework distinguishes attached and detached ADUs. Section 66314 includes a 1,200 sq ft detached limit and a 50 percent floor-area relationship for an attached ADU when there is an existing primary dwelling. Section 66321 then limits how restrictive local standards can be. Read those provisions together rather than treating the percentage as the entire answer.

Local maximum-size limits cannot fall below 850 sq ft, or 1,000 sq ft when an ADU has more than one bedroom. Separate protections prevent certain floor-area, lot-coverage, open-space, front-setback and minimum-lot-size requirements from blocking an eligible 800 sq ft ADU with compliant height and four-foot side and rear setbacks. The precise approval category remains important.

Does a small primary house force me to build a tiny attached ADU?⌄

Not necessarily. The 50 percent attached-unit provision must be read with the protections in section 66321. For example, simply calculating half of a 1,000 sq ft house and declaring a 500 sq ft maximum ignores the statutory protections against overly restrictive local size limits. Have the applicable sections and proposed bedroom count identified in the planning review.

An attached addition also changes the original building. Structure, roof connections, fire separation and existing openings may influence the practical design. A protected size allowance is a planning rule, not a guarantee that a particular attachment point is straightforward or economical to build.

How tall can it be?

For detached ADUs, state height protections begin at 16 feet. An 18-foot allowance applies within one-half mile walking distance of a major transit stop or high-quality transit corridor, as defined by the statute. That transit category also includes an additional two feet to accommodate a roof pitch aligned with the primary dwelling. Another 18-foot protection applies on a lot with an existing or proposed multistory multifamily building.

For an attached ADU, the protected height allowance is 25 feet or the primary dwelling’s applicable zoning height limit, whichever is lower. This does not require a local agency to allow more than two stories. These figures describe limits on how restrictive local standards may be, not a single citywide promise that every ADU can be built to that height.

Can I assume a nearby bus stop permits a taller ADU?⌄

No. The transit definitions used for height and parking are not identical. The height provision references a major transit stop or high-quality transit corridor and a walking-distance test. A parking exemption uses its own statutory conditions. Confirm the qualifying transit facility and walking route for each claimed benefit.

Put the supporting information in the project file. A straight line on a map can overlook an inaccessible route or physical barrier. The building’s roof design, the primary house and any applicable safety requirements should be reviewed before using the additional height in a final layout.

Sources: Government Code 66314 and 66321.

Setbacks, placement and access

Side and rear setbacks are distances from legal property lines, not from the nearest fence, hedge or neighboring building. Under the applicable state ADU provisions, new construction generally cannot be required to have side or rear setbacks greater than four feet. An existing-space conversion or a qualifying replacement in the same location and dimensions has a different protection against new setback requirements.

That distinction is particularly useful for garages built closer to a boundary than a new structure would normally be placed. It does not remove the need to examine wall construction, openings, eaves and fire safety. A building can have a protected location while still requiring changes to become a lawful dwelling.

Does a zero-setback conversion mean I can add windows on the boundary?⌄

No. Setback relief and building-code requirements answer different questions. Retaining a garage footprint does not automatically authorize a new window, door or roof projection near a property line. Have the design show the existing walls, proposed openings and required construction assemblies together.

This is also why a generic floor plan may not work when mirrored onto a tight lot. A bedroom window placed on the wrong wall can create a major design problem. Solve ventilation, light, emergency escape where applicable and privacy as part of the conversion layout, not after the room arrangement is fixed.

Can the ADU go in the front yard?⌄

Do not assume either a universal prohibition or unrestricted permission. Section 66321 prevents certain front-setback requirements from precluding an eligible 800 sq ft ADU, but that protection operates within a specific statutory framework. The proposed placement still needs a property-specific review of access, safety, utilities and the qualifying pathway.

A front-yard option may also compete with the existing entrance, driveway or service equipment. Compare it with other arrangements on the site. The most useful question is which compliant location delivers a workable home and preserves safe access, rather than which corner looks empty in an aerial photograph.

What about distance between buildings?

Do not import a universal six-foot separation number from another city’s guide. Building separation, wall ratings, openings and fire requirements depend on the project. Show actual distances between the house, ADU and other structures, then resolve the applicable requirements with the design and reviewing teams. A property-line setback is not the same measurement as separation between two buildings.

State law also says an ADU cannot be required to have a “passageway” as defined in the ADU statute. That does not mean physical access, emergency considerations or utility maintenance can be ignored. Plan a usable route to the dwelling and consider how construction materials, waste and equipment will reach the work area.

Sources: Government Code 66314, setbacks and passageways and 66321, protected development standards.

Parking rules and exemptions

Parking should be checked early, but it is not automatically a barrier to an ADU. Where parking can be required, the state framework caps the requirement at one space per unit or bedroom, whichever is less. Tandem parking may be permitted under the statute. Several exemptions can eliminate the ADU parking requirement altogether.

Section 66322 includes exemptions for an ADU within one-half mile walking distance of public transit, an ADU within a qualifying historic district, and an ADU that is part of the proposed or existing primary residence or an accessory structure. It also covers circumstances involving unavailable on-street permits, a car-share vehicle within one block and specified concurrent primary-dwelling applications.

Must I replace parking when converting a garage?⌄

State law says replacement off-street parking cannot be required when a garage, carport, covered parking or uncovered parking is demolished or converted in conjunction with an ADU. Keep the distinction clear: removal of existing parking and a requirement for new ADU parking are related but separate questions, both addressed by the statute.

A driveway still has practical uses. Think about deliveries, accessible circulation, refuse storage and the residents’ actual transportation needs. Choosing to retain a useful parking space is different from accepting a requirement that the applicable law does not permit.

What proof should support a parking exemption?⌄

Identify the exact exemption and provide the information needed to establish it. For transit, record the qualifying stop and walking route. For a conversion, show the existing structure and proposed scope. If relying on permit-parking conditions or car share, verify those circumstances rather than assuming they apply throughout the neighborhood.

A written parking note on the site plan helps prevent different reviewers or consultants from making conflicting assumptions. If the project changes from a conversion to a substantially different new building, revisit the exemption rather than carrying the original conclusion forward automatically.

Sources: Government Code 66322, parking exemptions and 66314, parking limits and replacement parking.

Interior requirements and junior ADUs

An ordinary ADU must function as an independent dwelling. A spare bedroom with a bathroom is not automatically an ADU, and a backyard office is not automatically approved for residential occupancy. The plans need to establish the facilities and building conditions required for the proposed use.

For everyday design, consider how someone will cook, sleep, store belongings, move through the home and use the bathroom. A technically large floor area can still produce an awkward dwelling if circulation consumes too much space. Conversely, a compact unit can work well when the kitchen, bathroom and entry are coordinated rather than added as afterthoughts.

How is a JADU different from an ADU?⌄

A junior ADU is limited to 500 sq ft and is created within the walls of a qualifying single-family residence; an attached garage is included in the statutory framework. It needs a separate entrance and an efficiency kitchen with cooking appliances, preparation space and storage. A JADU may share sanitation facilities with the main residence under the applicable conditions.

When sanitation is shared, the statute requires an interior entry to the main living area. A JADU also carries a recorded deed restriction addressing separate sale and its required characteristics. It should be selected because the arrangement fits the household and property, not simply because the name sounds like a smaller detached ADU.

Must the owner live on the property?⌄

Ordinary ADUs are not subject to an owner-occupancy requirement under section 66315. The 2026 JADU statute makes a more specific distinction: owner occupancy is required when the JADU shares sanitation facilities with the existing structure, subject to the listed ownership exceptions. A JADU with its own sanitation facilities does not carry that same owner-occupancy requirement under section 66333.

Do not rely on an older checklist saying every JADU always requires owner occupancy. Review the current statute, the proposed bathroom arrangement and the recorded restrictions that will apply. If future rental or sale flexibility matters to you, resolve those obligations before committing to the JADU design.

Does building an ADU force sprinklers into the existing house?⌄

The state ADU framework says sprinklers are not required in the ADU if they are not required for the primary residence, and ADU construction does not itself trigger sprinklers in the existing primary dwelling. The project still needs a review of its actual building and fire conditions.

Avoid treating that protection as a general exemption from all fire-safety measures. Wall assemblies, openings, alarms and other applicable requirements are separate subjects. Explain any concurrent work on the primary dwelling so the reviewing team can distinguish ADU-related work from a broader alteration project.

Sources: Government Code 66313, definitions, 66315, 66333, JADU requirements and 66314, sprinklers.

Garage conversions and unpermitted units

A garage conversion can reuse an existing footprint, but the existing building must be understood before the design is priced. Review foundations, framing, roof condition, drainage, floor levels, utility service and the proposed openings. A garage designed to store vehicles may need substantial work to function as comfortable residential space.

Separate the question “Can this footprint qualify?” from “What must be rebuilt?” A protected setback does not establish the condition of a slab. A finished-looking room does not establish that residential work was permitted. Existing records and a physical assessment should inform the scope together.

Can I extend an existing conversion?⌄

Under the section 66323 conversion category, an expansion of up to 150 sq ft beyond the existing accessory structure’s dimensions is permitted only for accommodating ingress and egress. It is not a general allowance to add 150 sq ft of bedroom or living space under that conversion provision.

If you want a larger addition, investigate the appropriate alternative or combined scope instead of labeling all new construction a conversion. Draw the existing and proposed footprints distinctly. That makes the setback, structural and size analysis more transparent and helps avoid a late disagreement about the project’s approval category.

What if the existing ADU was never permitted?⌄

Government Code 66311.7 provides a specific pathway for unpermitted ADUs and JADUs constructed before January 1, 2020. It limits denial based on certain building or ADU-standard violations, while retaining health-and-safety protections and excluding buildings deemed substandard under the referenced law. The construction date and existing conditions therefore matter.

The statute also describes confidential third-party inspection before application and limits certain fees for qualifying legalization projects. This is not an automatic certificate of occupancy or a promise that no corrective work will be needed. Gather evidence of the unit’s age and condition, then establish the correct legalization process with the city.

Sources: Government Code 66323, conversion category and 66311.7, pre-2020 unpermitted units.

Coastal, hillside and historic properties

A Los Angeles address can involve very different physical and planning conditions. A relatively level inland parcel, a hillside site and a property in the coastal zone should not begin with identical assumptions. The purpose of the early property review is to identify which additional questions are relevant, not to assume that every overlay prohibits an ADU.

Use ZIMAS and the appropriate agency records to identify mapped conditions. Then connect those findings to the actual proposal. A slope may affect foundations and access; an easement may affect placement; a historic designation may require a more careful review of proposed exterior work. A mapped label alone does not tell you the complete construction scope.

Do coastal ADUs follow different rules?⌄

The Coastal Act remains relevant. Government Code 66329 does not generally remove its application to ADUs. The current statute also establishes a 60-day completed-application framework for coastal ADU permit decisions and concurrent processing, with specific provisions for local governments and the Coastal Commission.

Confirm whether the property is actually within the coastal zone, which agency has permitting authority and what coastal application is needed. Proximity to the ocean is not a substitute for a boundary check. Likewise, an inland mailing address does not by itself settle whether coastal jurisdiction applies to the parcel.

What should be checked on a hillside site?⌄

Discuss the slope, access, retaining structures, drainage and foundation approach before selecting a standard footprint. Ask the design team which investigations are needed for the actual scope and ground conditions. This guide does not assign one universal soils-report requirement or hillside surcharge to every Los Angeles ADU.

Compare options with those conditions in mind. A location that appears spacious in a photograph may require difficult excavation or material access. A smaller design in a more practical location can sometimes fit the household’s goals better. That is a design and cost comparison to make with project information, not a blanket rule.

Sources: LA City Planning zoning search, Government Code 66329 and California Coastal Commission permit information.

Permits, review deadlines and standard plans

State ADU law generally provides ministerial review, meaning a qualifying application is reviewed against applicable standards rather than through a discretionary public hearing. The practical task is to submit a coordinated application that establishes compliance. Site information, architectural drawings, structural work and other required documentation need to describe the same project.

Completeness is a separate milestone

Under the current section 66317, the agency has 15 business days to determine whether an ADU application is complete and provide the specified written notice. An incomplete notice must identify missing items. The statute also addresses resubmissions and limits additions to the missing-information list. Keep dated submission receipts and written responses so the project’s status is clear.

The generally applicable approval-or-denial period is 60 days from a complete application when an existing dwelling is on the lot. A project submitted with a new primary dwelling has different timing provisions. An applicant-requested delay can toll the period. These distinctions should be reflected in the schedule rather than hidden inside an optimistic “two-month permit” promise.

If the city misses the deadline, can construction start immediately?⌄

The statute includes deemed-approval provisions, but do not treat a calendar calculation as permission to begin unrecorded construction. Establish the application history, the applicable deadline and the documented permit status with the agency. Starting work without the required permit documentation creates a different problem from asserting a statutory review right.

When an application is denied, section 66317 requires written comments describing defective or deficient items and how they can be remedied. Use that response to organize corrections. Maintain a versioned drawing set and a response list so the next submission clearly addresses the identified issues.

Will an approved standard plan eliminate plan check?⌄

No. Los Angeles offers an approved standard-plan program, but a pre-reviewed building design is not approval for every property. The selected plan still needs a site-specific fit, zoning review and foundation information. Confirm that the plan is actually part of the city’s program rather than merely advertised online as permit-ready.

Standard plans are most useful when their layout and construction assumptions align with the site. If extensive changes are needed, compare the revised scope with a custom design. The decision should account for adaptation, engineering and site work, not just the advertised plan price.

Sources: Government Code 66317, application procedures and LADBS ADU and standard-plan information.

ADU fees, utilities and construction budgeting

A useful budget separates design and documentation, agency fees, utility work, site preparation and building construction. These categories respond to different conditions. Avoid comparing a contractor’s building-only figure with another estimate that includes engineering, service upgrades and difficult site work.

What is the impact-fee exemption?

Government Code 66311.5, effective in 2026, exempts an ADU with 750 sq ft of interior livable space or less from impact fees. A JADU with 500 sq ft or less is also covered. For an ADU larger than 750 sq ft, the statute provides proportional impact-fee treatment in relation to the primary dwelling’s square footage.

“Impact fee” is a defined category. The exemption does not mean that plan-check fees, building permits, utility connections and every other charge disappear. The statute expressly distinguishes utility connection fees and capacity charges. Request an itemized agency estimate and identify the legal basis for each charge rather than relying on a single total called “permit fees.”

Do conversions need separate utility connections?⌄

For the qualifying conversion category in section 66323(a)(1), section 66311.5 protects against a required new or separate direct utility connection and related connection or capacity charges, subject to stated exceptions such as construction with a new single-family dwelling or specified separate conveyance. Other ADU categories can be treated differently.

This does not establish that existing pipes, service equipment or electrical capacity can support every proposed design without work. Ask the relevant utility and project team to evaluate capacity and routing. Distinguish a legal connection requirement from the physical improvements needed to make the proposed installation function safely.

What makes two similar-sized ADUs cost differently?⌄

Important variables include the foundation approach, existing structure condition, access, utility routes, finish selections and the amount of work to the primary property. A conversion with substantial structural repair can have a different cost profile from a straightforward new building. The floor area alone cannot settle that comparison.

Request a scope that identifies assumptions, exclusions and unresolved items. Ask who handles design, engineering coordination, permit responses, utility coordination and inspections. Comparing those responsibilities helps you evaluate proposals fairly and reduces the risk of discovering missing work after selecting a contractor.

Source: Government Code 66311.5, fees and utility connections. Current project charges should be confirmed with the responsible agencies and providers.

Renting, ownership and future use

Decide how the ADU will be used before finalizing the design. Housing a parent, accommodating an adult child and operating a rental can lead to different priorities for privacy, storage and circulation. Those choices do not replace the legal requirements, but they help produce a home that fits the intended resident.

The state-exempt ADU categories in section 66323 and the JADU provisions require rental terms longer than 30 days. Other applicable local restrictions must also be checked. Do not treat an ADU permit as authorization for vacation-rental use or project short-term-rental income without separately establishing legality.

Does an ADU affect rent-stabilization or registration obligations?⌄

It can. The Los Angeles Housing Department explains that ADUs and JADUs can interact with rental registration and Rent Stabilization Ordinance coverage depending on the property’s circumstances, including the existing housing. Permit approval and lawful rental operation are separate steps.

Review the property’s history with LA Housing before making assumptions about future rent increases, exemptions or registration. A newly built unit does not justify assuming that every dwelling on the parcel has identical treatment. Keep any agency determination with the property’s operating records.

Can the ADU be sold separately from the main house?⌄

Do not assume so. The ordinary ADU framework generally ties the unit to the primary property, while separate conveyance is addressed through specific statutory mechanisms and conditions. A JADU deed restriction includes a prohibition on sale separate from the single-family residence. An ordinary building permit is not a subdivision approval.

If separate ownership is essential to your plans, identify the currently available local process and required legal work before designing around that goal. This guide does not represent that Los Angeles has approved a particular separate-sale pathway for your parcel.

Sources: LA Housing’s ADU guidance, Government Code 66323, 66333 and 66342.

Los Angeles ADU regulations comparison chart

Use these three comparisons together. The first identifies the project pathway, the second covers dimensions and site rules, and the third addresses approvals and ongoing obligations. The tables adjust to your screen so you can compare the rules together. Each rule includes its qualifying condition and a direct source so you can check the provision behind the summary.

Scope: City of Los Angeles planning guide, checked November 6, 2026. State protections are identified below; property-specific local and building requirements still need review. “Protected allowance” means a limit on how restrictive a local standard may be, not automatic approval of a particular design.

Compare the approval pathways

Compare dimensions, placement and parking

Compare permits, fees and use requirements

From the first sketch to a completed ADU

1. Establish the property facts

Confirm jurisdiction, existing permitted dwellings, the proposed unit type and the site’s known constraints. Collect records before assuming that an existing garage or room can be reused exactly as it stands. The goal is a documented starting point that everyone on the project understands.

2. Compare practical layouts

Evaluate the footprint, resident needs, access, privacy and utility routing together. Compare alternatives using the same scope assumptions. A useful design review explains what each option changes, including whether it uses a different approval pathway or requires more work to the primary house.

3. Coordinate the application

Prepare a consistent drawing set and the supporting documents required for the project. Track agency submissions, completeness notices and correction responses. Keep proposed changes coordinated across architectural, structural and building-system information so one correction does not create a conflict elsewhere.

4. Confirm the construction scope

Before construction, align the permitted design with the contract, exclusions, selections and schedule. Identify unresolved utility work and site conditions. Confirm who manages inspections and documentation. A clear scope helps distinguish a genuine change requested by the owner from work that was always necessary but omitted from an estimate.

5. Complete inspections and operating checks

Follow the required inspections and obtain the applicable completion documentation before occupancy. If the ADU will be rented, address registration and operating requirements separately. Keep approved drawings, inspection records, warranties and equipment information together for future maintenance or property transactions.

Questions to bring to your ADU consultation

Can you tell me the maximum size from my address alone?⌄

An address starts the review, but reliable advice also depends on records, existing buildings and the proposed pathway. A preliminary conversation can identify likely options and missing information. A measured, coordinated feasibility review is what turns those possibilities into a design basis.

Bring your priorities as well as your desired square footage. An extra bedroom, easier access for a parent or separation from the main yard may be more valuable than maximizing area. Uni Construction can use those goals to frame the design and construction questions that need answers next.

Should I choose an ADU type or a floor plan first?⌄

Start with the property and the type of project it can reasonably support. Then compare floor plans that fit that pathway. Selecting a detached plan before discovering that the practical option is a garage conversion usually creates avoidable redesign.

Our ADU types guide explains the basic differences. The regulations on this page help you understand why those differences affect size, placement and approval. Use both alongside a site review rather than treating either as a parcel-specific approval.

What information helps you estimate the next stage?⌄

Share the address, available records, photographs and your intended use. Tell us about known site issues and any target budget or timing constraints. Identify whether you need design, engineering coordination, construction or a coordinated scope covering several stages.

The first discussion should clarify what is known, what still needs investigation and what service is appropriate next. You can book a 30-minute consultation to discuss those decisions with Uni Construction.

Official sources and review notes

The numerical rules in this guide are linked to California’s ADU statutes, with City of Los Angeles sources used for local agency and program information. State protections and local procedures must be read together. A dated guide should be rechecked when the law changes or the project scope changes.

• California Government Code, ADU chapter: definitions, approval pathways, dimensions, parking, fees and JADUs.
• Government-hosted copy of the 2026 ADU statutes: statutory text used to cross-check the provisions summarized here.
• California HCD ADU resources: state guidance and handbook access.
• LADBS ADU information: building review and approved standard-plan program.
• Los Angeles City Planning zoning search: property zoning and mapped planning information.
• Los Angeles Housing Department ADU guidance: rental-property considerations.
• California Coastal Commission permit information: coastal permitting resources.

This guide provides planning information, not a determination that a particular property or drawing is approved. It does not promise a universal permit fee, construction price or completion date. Confirm the proposed pathway and outstanding site questions before committing to construction.