LA ADU Feasibility Checker

California requires Los Angeles to allow at least one accessory dwelling unit on a single-family lot, and the review is ministerial, which means the city has no discretion to refuse an application that meets its standards. No hearing, no neighbor objection that counts, and no minimum lot size that can be held against you.

Three things decide the rest of it. The first is whether the property is inside the City of Los Angeles at all: a Los Angeles postal address is not a City of Los Angeles address. Santa Monica, West Hollywood, Long Beach and the unincorporated county each write their own standards, and none of the city figures on this page are theirs. It catches people in both directions, because most of the San Fernando Valley is inside the city under postal names that are not Los Angeles: Van Nuys, North Hollywood, Encino, Canoga Park, Reseda, Woodland Hills.

The second is the one restriction Los Angeles writes for itself, below. It closes the city's own route on certain lots and leaves the state-law route open, so it narrows a project rather than ending it. The third is what is already on the lot, because a single-family home, a multifamily building and a condominium are three different cases with three different counts.

California sets a floor under every ADU application in the state. Los Angeles can be more generous than that floor, and often is, and it cannot go below it. Each line here holds whatever a local standard says, which is why the state ADU law floor is worth reading before you argue with anybody about a setback.

A local development standard cannot preclude an ADU of at least 800 square feet with 4 foot side and rear setbacks; A maximum ADU size set below 850 square feet for a studio or one bedroom, or below 1,000 square feet above one bedroom. That is a separate protection from the one above and it is the one that answers a cap; At least 16 feet of height for a detached unit; No minimum lot size. A lot cannot be called too small for an ADU; A decision within 60 days, ministerially, with no hearing and no discretionary review; No owner-occupancy requirement for an ADU; Where parking may be required at all, no more than 1 space, and none where any one of the six exemptions applies. Which of them reaches a project turns on the ADU's type and pathway; Conversion of an existing garage, with the demolition permit issued alongside the ADU permit rather than separately; No impact fees under 750 square feet; No homeowners association prohibition, and no unreasonable restriction either.

The statutes were renumbered in 2024. What older articles and most contractors still call Government Code 65852.2 is now Government Code 66310 through 66342. Same law, two names, and a plan checker citing one is not citing something different from a plan checker citing the other.

Los Angeles prohibits its own ordinance ADU on a lot that is in a Very High Fire Hazard Severity Zone and in a Hillside Area. Both, not either. A lot in a fire severity zone on flat ground is not caught by it, and neither is a hillside lot outside a fire severity zone, which is why the checker asks the two questions separately instead of asking one. The ordinance names limited enumerated exceptions, which this site does not list. And the prohibition reaches the City's ordinance ADU, not every ADU. A state-law ADU, meaning a conversion of existing space or a detached ADU of up to 800 square feet, is generally still available on a lot that meets both conditions, and needs its own consideration under the Los Angeles rules rather than being read out of the project. So a lot in both zones is a narrower answer than it looks: the ordinance route is closed except under those exceptions, and the state-law route is the one to ask LA City Planning about.

The checker above asks the two questions separately for that reason, and it keeps both answers editable after it gives a verdict. These are the only inputs on this site that you supply rather than we look up, so a mis-tap has to be correctable. Both are on the city's ZIMAS property map under the lot's planning and zoning details.

The distinction between the two routes is the part worth carrying away. A lot in both zones is not a lot where nothing can be built. What is closed is the City's ordinance ADU, the route the 1,200 square feet belongs to. A conversion of existing space, or a detached unit of up to 800 square feet, runs under Government Code 66323 instead and the prohibition does not reach it. Ask LA City Planning about the state-law pathway by name, because asking whether "an ADU" is allowed on a lot in both zones invites the answer that stops the conversation.

Everything else Los Angeles does is a standard rather than a prohibition, and a standard is the kind of thing the state floor sits underneath. That distinction is most of the answer to whether you can build here at all: a prohibition closes a route, and a standard is something the state puts a floor under.

Under the current Los Angeles ordinance an ADU may be rented but may not be sold separately from the primary home. The return on the project comes through rent over years rather than through a sale of the unit. That is a decision Los Angeles has made rather than a rule California imposes. AB 1033, passed in 2023, lets a city opt in to allowing ADUs to be sold separately as condominiums. Los Angeles has not adopted by LA as of 2026-09-30: the city has prioritized getting units built, with possible consideration in late 2026 or 2027. So separate sale is not available today and is the kind of thing that could change, which is worth knowing before a decision you will hold for twenty years.

The Los Angeles ordinance allows an ADU of up to 1,200 square feet, attached or detached. That is the maximum on the City's own ordinance pathway rather than a cap on every ADU at the address: the state-law pathways, a conversion of existing space in particular, are governed by Government Code 66323 and follow their own size rules. Underneath it sit two separate state protections, and they answer different objections. The first is about development standards: a local development standard cannot preclude you building an ADU of at least 800 square feet with 4 foot side and rear setbacks. Reach for it when a setback, a lot coverage rule or a specific plan is being used to squeeze the unit. The second is about maximum sizes: a local agency cannot set a maximum ADU size below 850 square feet for a studio or one-bedroom unit, or below 1,000 square feet for a unit with more than one bedroom. Reach for it when the city's own cap is the problem. The 800 square feet does not answer that one, and treating it as though it did is the most common way this subject is got wrong.

A detached ADU gets at least 16 feet. Within 0.5 mile walking distance of a major transit stop or a high-quality transit corridor that becomes 18 feet. Another 2 feet is allowed where it is used to pitch the roof to match the primary dwelling, which is the allowance that lets an ADU look like the house rather than like a box behind it. An attached ADU may go to 25 feet or the height of the primary dwelling, whichever is lower.

Side and rear setbacks are four feet, and a conversion of existing space adds none of its own: a garage already standing where it stands does not have to move, which is what makes converting a garage to an ADU the cheapest route on a narrow lot. The full set of numbers, including what happens when the primary dwelling is shorter than the ADU you want, is on the ADU size and height limits page.

Where parking may be required at all, the most a city may require is 1 space per unit or per bedroom, whichever is less. And it may require none at all in any of six situations, the common one in Los Angeles being a lot within 0.5 mile walking distance of public transit. Units created by converting existing space in a multifamily building carry no parking requirement whatever. Meeting any one of the six is enough; they are not conditions you have to satisfy together. Which of them reaches a particular project, and whether the cap applies to it at all, depends on the type of ADU and the statutory pathway it is built under, so treat these as the shape of the rule rather than as the answer for your lot. The six are: within half a mile walking distance of public transit; in a historic district; where the unit is part of the existing primary residence or of an existing accessory structure; where on-street parking permits are required but not offered to the occupant of the ADU; within one block of a car share vehicle; or where the application goes in with one to build a new primary dwelling.

On a single-family lot, California requires the city to allow at least 1 accessory dwelling unit and at least 1 junior ADU. That is a floor rather than a quota: it is the minimum Los Angeles has to permit, and the city cannot write a rule that gets you below it. Above the floor, HCD's guidance supports combining the state-law options in qualifying circumstances: one converted ADU, one detached ADU and one junior ADU, which is 3 units on the lot. That is a count of units rather than a license to build any three. Each is its own pathway with its own statutory requirements, so a lot with nothing to convert does not get the converted unit by arithmetic. Confirm the combination for your own lot with LA City Planning before you draw it.

On an existing multifamily property, California allows conversions of space that is not currently livable, such as storage rooms, passageways and attached garages, up to 25% of the existing units and never fewer than 1. Separately from those, it allows detached units up to the lesser of 8 or the number of units the property already has.

The junior unit in that pair carries a condition the full ADU does not, and it is the one that decides whether the unit is usable. A junior ADU is carved out of the house rather than built beside it, is capped at 500 square feet, and where it shares sanitation with the house the owner has to live in either the house or the junior unit. An owner who does not intend to live on the property is choosing between one usable option and one that is not.

A condominium is a third case and this site does not answer it with a number. Which of the two sets of counts reaches an individual condominium depends on the association's governing documents and on who owns the ground underneath, and nobody here has confirmed that. What does reach it is the homeowners association rule below. The counts for the other two, worked through with examples, are on the page about how many ADUs a lot allows.

A homeowners association cannot prohibit an ADU, and cannot unreasonably restrict one either. That is California Civil Code sections 714.3 and 4751, so it holds against a covenant written before the statute and against a board that has never had to apply it. Reasonable conditions are a different matter and are still available to an association, which is where these disputes actually happen.

The city has 60 days to approve or deny a complete ADU application. Before that clock starts it has 15 business days to tell you whether the application is complete, in writing and with the missing items named, so an application cannot be left in a drawer without a response. The review is ministerial, which is the part that matters more than the number of days: there is no hearing, no discretionary finding and no opportunity for a neighbor to object, because nothing about the decision is a judgement call. An application that meets the standards is approved.

That second word does more work than the number. It means there is no hearing at which a neighbor objects, no finding anybody has to make, and no discretion to exercise, so the only question is whether the application meets the standards. It also means the way to lose time here is an incomplete application rather than an unpopular one: before the sixty days starts at all, the city has fifteen business days to tell you in writing whether the application is complete and to name what is missing.

Los Angeles runs a pre-approved plan program, so a design that has already been through plan check can be permitted faster than one drawn from scratch. What it costs, which plans are in it and how much time it saves are not things this site has read from the city, so we name the program rather than describing it. LA City Planning publishes the current list.

An ADU project on a property with tenants stops being only a planning question. If the building is covered by the Rent Stabilization Ordinance, the checker on the rent increase calculator will say so from the same address, and a rent stabilized unit carries eviction rules that a construction schedule does not override.

Displacing a tenant to build has a price attached to it, and it is not a small one. Work it out on the relocation assistance calculator before the plans are drawn rather than after, because the figure changes what the project costs by more than most of the decisions on the drawing.

Renting the finished ADU out by the night is a separate question again, with its own answer and mostly a no. The short-term rental checker runs the same address against the Home-Sharing Ordinance.

This site does not publish a cost estimate for building an ADU in Los Angeles, and that is a decision rather than an omission. The ranges in circulation come mostly from companies selling the work, they vary by a factor of three for the same description, and the figure that decides whether your project is affordable is the one for your lot rather than an average of somebody else's. Get three written quotes on the same scope and compare those. What this site can tell you is what you are allowed to build, which is the part the quotes have to be written against.

We do not publish a permit fee figure. LADBS sets plan check and permit fees on a schedule that changes, several departments charge against one ADU project, and the amounts quoted in summaries of it disagree with each other by enough to matter to a budget. Ask LADBS for the current schedule, and ask for it in writing.

The CalHFA ADU Grant Program is not currently available. It paid up to $40,000 toward predevelopment costs, meaning the design, the permits and the site work rather than the build itself. Its funding was fully allocated in December 2023 and no new round has been announced. Anything you read describing it as open is describing the program as it was, and there is no waiting list to join. Do not build a budget around it.