Can you build two detached ADUs instead of one?
Beginning January 1, 2027, AB 956 expands a specific state-law approval pathway from one to two detached, newly constructed ADUs on a qualifying lot with an existing or proposed single-family dwelling. Governor Newsom signed the bill on September 29, 2026; it is Chapter 791.
That is a meaningful planning opportunity, but it is not a promise that every house can accommodate two additional homes. The provision applies within residential or mixed-use zones and remains subject to the statute's conditions and applicable building requirements.
The chaptered AB 956 text is the primary source. Its amendment to Government Code Section 66323 is the key provision for homeowners.
What changes—and what does not
| Question | What AB 956 provides |
| --- | --- |
| How many detached new-construction ADUs? | Two under the qualifying Section 66323 pathway, rather than one |
| How large? | A local agency may limit each to 800 square feet of livable space under this pathway |
| Side and rear setbacks? | No more than four feet under this provision; other applicable safety requirements still matter |
| Height? | Applicable statutory height limits still apply |
| Does it split the property? | No. An ADU approval is not a subdivision approval |
| Is another JADU guaranteed? | No. The agency need not ministerially approve a JADU where the two detached ADUs have been constructed |
Do not read the 800-square-foot provision as a statement that every California ADU must be that size. Other approval pathways can have different standards. Equally, do not assume that two 1,200-square-foot units are guaranteed by this bill.
Why the JADU detail matters
The bill expressly addresses a common misunderstanding: two detached ADUs do not automatically come with a guaranteed additional junior ADU. Section 66323 also contains a conversion-ADU category, but combinations need to be evaluated under the actual statutory language and the property's existing units.
Before selecting a floor plan, document every permitted and unpermitted structure on the lot. A property with an existing ADU is not the same planning exercise as a property with only a main house.
How this affects LA and Orange County planning
The first question is the property's jurisdiction. A City of Los Angeles property goes through a different agency from a property in Whittier, Anaheim or Santa Ana. A mailing address alone may not settle that question.
For a two-unit concept, review:
- Where both units and their entrances could fit without assuming a setback exception.
- Sewer routing, electrical capacity and utility coordination.
- Construction access, staging and the impact on people living in the main house.
- Easements, slopes, drainage, fire access and any applicable coastal or historic constraints.
- Whether two smaller homes or one larger unit better serves the household's goals.
AB 956 also changes certain private-restriction protections from lots zoned “for” single-family residential use to lots zoned “to allow” that use. It does not mean every HOA rule disappears; reasonable restrictions and the applicable statutory limits still require review.
Prepare now without treating 2027 rules as current permits
Gather an existing site plan, permit records, utility information and your intended use for each unit. Compare layouts before ordering a final design. Ask the city how it will handle an application submitted before the new law takes effect; do not assume it will automatically receive the new entitlement.
Explore real Vision ADU projects, or review our Anaheim, Santa Ana and Whittier pages.
Discuss a two-ADU property review. We can help evaluate the site and design options; the reviewing agency determines permit approval.
Frequently Asked Questions
Does AB 956 allow two detached ADUs on every property?
No. It expands a specified ministerial approval pathway for qualifying lots with an existing or proposed single-family dwelling. Site conditions, the chosen pathway and applicable requirements still matter.
Does ministerial approval mean no permit is needed?
No. It means the agency checks compliance without discretionary review under the applicable pathway. You still need the required permits before construction.
Can I sell the two ADUs separately?
AB 956 does not itself create a right to sell them separately. Separate conveyance and subdivision involve different legal pathways and requirements.
Read the What's Coming in 2027 series
- Part 1: AB 956 and two detached ADUs
- Part 2: SB 1117 and ADU impact fees
- Part 3: AB 1621 and housing permit reviews
- Part 4: AB 2601 and concurrent lot-split processing
Research checked October 21, 2026 against the chaptered California bills. This series explains signed legislation for 2027 planning, not permission to start work today. General educational information, not legal advice. Confirm the applicable law, permit pathway and property conditions with the reviewing agency and qualified professionals before committing to a project.