Building an ADU first after the Palisades or Eaton fire

After the January 2025 fires, many owners in the Palisades and Altadena want a place to live on their own property while the main home is rebuilt. A detached ADU is smaller and faster to design, permit and build than a full house, so it can be finished first. Three sets of rules make that possible: a state law, AB 462; the City of Los Angeles's rebuild orders for the Palisades; and LA County's ordinance for the Eaton fire area.

What AB 462 changed for fire-damaged properties

AB 462 took effect on October 10, 2025, as an urgency law. It lets a detached ADU get its certificate of occupancy, the approval to live in it, before the main home is rebuilt. Three things have to be true:

• A declared emergency. The county is under a state of emergency of the kind the law covers.
• A damaged main home. The main home was substantially damaged or destroyed in that event.
• A permitted ADU. The ADU has its permits and has passed its inspections.

ADUCheck's rules apply this to the Palisades fire area in the City of Los Angeles and the Eaton fire area in unincorporated Altadena. Ask your building department to confirm that your property qualifies before you plan around it.

AB 462 also changed coastal review, which matters in the Palisades. Where the city has a certified local coastal program, the coastal development permit decision is due within 60 days, and appeals to the Coastal Commission are removed. Where there is none, the Coastal Commission reviews on a 60-day clock.

The usual ADU rules still apply

The ADU itself follows the same state rules as any other. A detached ADU can be up to 1,200 sq ft, and a city must always allow at least 800 sq ft at 16 ft tall with 4 ft setbacks from the side and back of the property. Since January 1, 2026, every square-foot limit means interior livable space; walls, garages and decks do not count.

No development impact fees apply to an ADU of 750 sq ft or less, and no school fees to one of 500 sq ft or less. The city has 15 business days to say whether an application is complete and 60 days from a complete application to approve or deny it. See how long an ADU permit takes.

Rebuilding in the Palisades under the Mayor's Executive Order 1

Mayor Karen Bass issued Revised Emergency Executive Order No. 1 on March 18, 2025. City Planning and LADBS published guidelines for it on April 16, 2025. What they say about ADUs:

• An ADU on its own counts. Attached and detached ADUs proposed under the city's ADU code (LAMC 12.22 A.33) and state law (Gov. Code § 66323) are eligible projects, whether or not they are proposed with a main home rebuilt under the order.
• A garage can become the ADU. A repaired or replaced garage or accessory building may be converted to an ADU. The conversion can be permitted with the main home, before it or after it. A garage that existed before the fire and is rebuilt as an ADU stays within 110% of its old footprint and height, in substantially the same location.
• An attached ADU is outside the 110% limit. A new attached ADU does not count against the main home's 110% footprint limit. It follows state and local ADU law instead.
• Bluffs in the Coastal Zone. A new detached ADU in the Coastal Zone sits at least 10 ft from a canyon bluff or 25 ft from a coastal bluff. A California-licensed professional engineer or geologist prepares a bluff analysis to find the bluff edge, and the plans show it.
• No change in the number of homes. Apart from ADUs, projects under the order cannot add or remove main homes.

LADBS takes the permits. The city's recovery site, recovery.lacity.gov, lists the current steps and its rebuilding center. LA County's recovery site also lists a Palisades Permitting Center at 16925 Marquez Avenue, Pacific Palisades. For more on the Palisades orders, see rebuilding in the Palisades.

Rebuilding in Altadena under the Eaton fire ordinance

In unincorporated LA County, the Board of Supervisors adopted Interim Ordinance No. 2025-0034U for the Eaton fire area. In July 2026 it extended the ordinance for one year, to August 22, 2027. The county says that is the second and final extension the law allows.

• Like-for-like rebuilds. A rebuild that replaces what burned may change the floor area, size, height or footprint by up to 10% or 200 sq ft, whichever is greater. A rebuild beyond that follows current zoning, with a front setback of at least 20 ft.
• ADUs with the rebuild. A like-for-like rebuild may include new ADUs and junior ADUs, as long as they meet the county's ADU rules in Title 22.
• A standalone ADU first. The ordinance defines a standalone ADU as a new ADU on a damaged or destroyed property that has no main home. A household may live in a standalone ADU while it waits for the rebuild, until January 7, 2030. That is five years after the county proclaimed the local emergency.
• Parking. No replacement parking is required when an ADU fully or partly overlaps the footprint of a covered parking structure that burned.
• Time to use the approval. An approved application is used by January 7, 2030. The director may extend that once, for up to a year, if the request is filed in time.

The Altadena One-Stop Permit Center is at 464 W Woodbury Rd, Suite 210, Altadena, phone (626) 424-6743. Walk-in hours are Monday to Friday, 8:00 a.m. to 4:30 p.m., with last call for permits at 3 p.m. For unincorporated areas in the Palisades fire, the Calabasas One-Stop Permit Center is at 27001 Agoura Road, Suite 250, open for walk-ins Monday to Friday, 7:00 to 11:00 a.m. For fee deferrals and self-certified plans, see rebuilding in Altadena.

Building codes and fire-ready construction

LA County's recovery site says the Governor's Executive Order N-29-25 suspends the 2025 California Building Standards Code, and its rooftop solar and battery requirements, for rebuilding structures affected by the Eaton and Palisades fires. Ask your architect and the building department which code applies to your ADU, since a new ADU is not always a rebuild of something that burned.

Much of both burn areas is in a fire hazard severity zone. There, a new ADU is built to the California Wildland-Urban Interface Code. LA County's construction notes list what that means:

• Roof. A Class A fire classification.
• Vents. Listed to ASTM E2886, or covered with noncombustible, corrosion-resistant mesh with openings from 1/16 in to 1/8 in. No vents on the underside of eaves unless the code's conditions are met.
• Windows. Multi-pane glass with at least one tempered pane, glass block, or a 20-minute rating.
• Gutters. Noncombustible, with a way to keep leaves and debris out.
• Before final approval. The property meets the vegetation management requirements.

In the City of Los Angeles, a detached ADU in a very high fire hazard zone or a hillside area reads Check with LADBS on an ADUCheck report. The city may limit ADUs there on streets narrower than its standard, and an ADU far from a fire hydrant may need fire sprinklers. Those rules are still being confirmed against the current city text.

Check the property before you design

A guide is a starting point, not a permit. Before you pick a plan, run the free fire check for the address. It shows the fire hazard zone, the fire department that inspects, past fires nearby and the rules that apply. Then check the address for which kinds of ADU fit and where a detached ADU can go on the property.