California’s New ADU Rules 2025

California has moved into a new era for ADUs. After years of legislative changes, emergency wildfire orders, and local programs designed to speed up approvals, the rules now heavily favor homeowners who want to add an ADU or rebuild with modern, factory built housing. What used to take months of uncertainty is becoming a predictable process. The only challenge is understanding how the new laws and local programs interact so you can take full advantage of them.

The 2025 ADU Law Package In Plain English

AB 1033 is one of the most meaningful changes in recent years. In cities that choose to participate, a homeowner can now legally split an ADU from the main residence and sell it as its own condominium. This is the first time the state has allowed an ADU to become its own separate property interest. In practice, this transforms an ADU from a passive improvement into a potential low cost ownership opportunity for buyers. For homeowners, it creates a new exit strategy. Instead of selling the entire house, they can sell the ADU independently and retain ownership of the main home or vice versa. Although cities must choose to opt in, many are evaluating the program because it increases homeownership without new infrastructure burdens.

AB 976 eliminates owner occupancy requirements for most ADUs. Before this law, many cities required the property owner to live in either the primary residence or the ADU. That rule limited the ability to rent both units and created unnecessary enforcement burdens. The new rule is simple. A homeowner can rent both the ADU and the primary home without living on the property. This change improves rental flexibility, makes properties more attractive for investors, and brings California more in line with other states that already treat ADUs as standard rental housing.

SB 897 continues the state’s push toward simpler, faster approvals. It increases the maximum allowed height for many ADUs, which makes two story layouts and over garage units easier to build. The law also prohibits cities from denying an ADU because of old zoning violations or unpermitted work unless a real health or safety problem exists. This is important because many older homes in Los Angeles and throughout the state have legacy issues that were difficult or impossible to correct. SB 897 removes that obstacle and ensures cities focus on the proposed ADU itself, not unrelated historical issues.

AB 1154 clarifies several rules for Junior ADUs and smaller units. The law confirms that Junior ADUs with their own bathrooms are not subject to owner occupancy rules, which increases flexibility for long term renting. It also relaxes parking requirements and design restrictions for units under approximately eight hundred square feet. One of the most useful changes is the removal of replacement parking requirements when a homeowner converts a carport or driveway into an ADU. This helps densely built areas where on site parking is already limited and where older driveways simply cannot meet modern parking standards.

State Timelines and Enforcement Standards Throughout 2025, state agencies have repeated the same message. ADUs must be approved within sixty days, and cities must use objective standards. Cities cannot create delay through design reviews, discretionary hearings, neighborhood opinion, or vague criteria. The only valid reasons for denial are clear health or safety concerns based on written code. This is a major improvement for homeowners who previously dealt with unpredictable review cycles and inconsistent enforcement.

SB 9: A Parallel Path for Non Wildfire Rebuilds Many homeowners do not realize that SB 9 is still active and continues to provide opportunities separate from ADU law. SB 9 allows a qualifying single family lot to be split into two legal parcels and allows up to two independent homes on each lot in certain cases. This can create a total of four homes on a property that once held only one. The law applies across California and is not limited to wildfire rebuilds. When combined with updated ADU laws, SB 9 can create powerful development flexibility. For example, an owner can pursue a lot split and build one full home and one ADU on the front parcel while building another home and ADU on the rear parcel, subject to local standards and infrastructure capacity. SB 9 remains a key tool for homeowners who want to expand their property’s potential in a legal, streamlined way.

If you are adding an ADU in 2025, cities have less room to drag their feet or hide behind design reviews, old violations, parking excuses, or occupancy rules. It is much harder for them to block a compliant ADU.

Los Angeles City and Los Angeles County ADU Programs

Los Angeles City and Los Angeles County have expanded their ADU Standard Plan programs. These programs give homeowners access to pre-approved ADU plans that have already cleared building code and structural review. This significantly shortens permit timelines because the city only reviews the site specific items instead of rechecking the entire building design.

Los Angeles City offers a large catalog of pre-approved ADUs. Los Angeles County offers its own catalog for unincorporated areas. Both programs reduce risk, shorten timelines, and eliminate repeated plan check cycles.

Abodu’s Studio, One, and Two models are designed to fit directly into the Los Angeles permitting system. These models match the standard plan criteria that the city and county want to see and allow homeowners to move through the approval process in a predictable and efficient way. When a homeowner selects one of Abodu’s pre-approved models, most of the design work is already complete on day one.

Wildfire Executive Orders and Factory Built Housing

After the recent Southern California wildfires, the Governor issued emergency orders that focus on fast reconstruction and rapid deployment of safe housing. These orders direct state agencies to shorten review timelines, streamline approvals, and prioritize factory built housing for temporary and permanent use on burned lots.

The orders allow homeowners to place a manufactured home, modular home, or RV on their property as temporary housing during the rebuild of the main home. In many cases, the temporary home can remain until the primary residence receives a certificate of occupancy. This gives fire victims a legal and stable housing option while construction is underway.

State fire standards also require noncombustible defensible space within the first five feet of any structure in high fire zones. Factory built ADUs and modular units are already designed with noncombustible or ignition resistant materials. Metal roofing, fiber cement siding, ember resistant vents, and simple soffit structures help reduce ember intrusion and meet Wildland Urban Interface requirements.

Why Factory Built ADUs Align With These Rules

Factory built ADUs align directly with California policy changes and wildfire requirements. The state wants predictable, code compliant housing that can be delivered quickly. Factory built construction satisfies these goals.

Factory construction happens at the same time as site preparation, which cuts the overall schedule. The designs are consistent from home to home, which means fewer corrections and fewer surprises during plan review. When a model is already preapproved, the homeowner avoids most redesigns and engineering delays.

For fire affected areas, factory built ADUs offer an advantage because they use noncombustible or ignition resistant materials and sealed construction that is difficult to achieve with field built framing. Homeowners can live in a factory built unit on site during the rebuild and then keep it permanently as an ADU after the primary home is complete. This creates long term value beyond temporary housing.

Abodu’s Studio, One, and Two models were created for exactly this type of environment. They are predictable, compliant with Los Angeles permitting expectations, and ready for installation with much shorter lead times than custom site built projects.

Recommended Next Steps for Homeowners

Homeowners in Los Angeles, Altadena, the Palisades, and other fire affected areas should follow a clear sequence.

Step 1. Confirm whether your property is in a fire hazard severity zone or a designated disaster area.

Step 2. Review Los Angeles City or Los Angeles County ADU standard plan options and compare them to Abodu’s preapproved Studio, One, and Two models.

Step 3. Ask your building department how the wildfire executive orders apply to your specific address and what documentation they need.

Step 4. Incorporate noncombustible materials and five feet of defensible space in all design decisions to comply with current fire standards.

Step 5. Decide early whether the ADU will stay permanently as a rental or family unit or whether it could be structured as a separate condominium if your city authorizes ADU condo conversions.