California Is About to Allow 2 Detached ADUs. HOAs Lose Their Veto.

Backyard ADUs in Los Angeles, where nearly half of California's early ADU permits landed. Dwell.

For eight years, California's deal with homeowners has been simple: one detached backyard house, approved by right, no discretionary hearing. On August 27 the Legislature voted to make it two. AB 956, now enrolled and sitting on Governor Newsom's desk, would require every city and county to ministerially approve up to two detached, new-construction accessory dwelling units on a single-family lot, and it rewrites the rule that lets a homeowners association stand in the way.

The short version:

• AB 956 raises the number of detached ADUs a local agency must approve by right on a single-family lot from one to two. It passed both houses and was enrolled September 1, 2026.
• Build two detached ADUs and you give up the guaranteed junior ADU on that same lot. The bill says a city is not required to approve a JADU where two detached units already stand.
• It amends the Davis-Stirling Act so association rules are void on any lot "zoned to allow" single-family use, not only lots "zoned for" it, widening the anti-blocking rule to more properties.

From the text

"This bill would increase the number of detached, new construction, accessory dwelling units that a local agency is required to ministerially approve on lots with a proposed or existing single-family dwelling, as described above, to 2. However, the bill would expressly state that a local agency is not required to ministerially approve an application for a building permit to create a junior accessory dwelling unit on the same lot where 2 detached, new construction, accessory dwelling units have been constructed." AB 956, Legislative Counsel's Digest.

What actually changed

Since 2017, state law has guaranteed one detached ADU by ministerial approval, meaning no public hearing and no neighbor veto, the baseline the state spells out in its own ADU handbook. AB 956 keeps that machinery and changes one number. One detached unit becomes two, each still held to the same 4-foot side and rear setbacks the current guarantee uses.

Read the second sentence before you celebrate. The bill hands you a second detached unit and, in the same breath, removes the junior ADU you could otherwise carve out of the main house. The tradeoff. A junior accessory dwelling unit is the cheapest unit on most lots, built inside existing walls with a shared entrance and a small kitchen. If you put up two freestanding structures, the city is no longer required to approve that interior JADU. You are choosing between three units on paper and two units you can actually finance.

Our read: the headline is the second detached unit, but the provision that helps more people is the HOA fix. The number of California lots that can physically hold two detached ADUs behind the main house, each with legal setbacks and its own access, is smaller than "two ADUs" makes it sound. The Davis-Stirling change is quieter and reaches further. It voids association rules that block a compliant ADU on any lot "zoned to allow" single-family use, closing a gap that let some HOAs argue their way out on technical zoning grounds.

Who wins and who loses

Winners: owners of deep lots, and anyone inside a homeowners association that has been slow-walking ADU applications. If you are a first-time ADU client with room for two cottages and a plan to rent both, AB 956 turns a maybe into a by-right approval. The unmoved: owners of standard 5,000 to 6,000 square foot lots, where a second detached structure runs out of yard before it runs out of ambition. For them the bill reads as a JADU they can now lose, not a second house they can now build.

The cross-street check. California is catching up here, not leading. Washington's HB 1337 already forces cities inside urban growth areas to allow two ADUs per lot with no owner-occupancy requirement, codified at RCW 36.70A.681; California is only now reaching two detached units, and only for new construction. On the HOA question, Oregon is moving the same way on a later clock: its HB 2138 bars associations from banning ADUs starting in 2027, as we noted when that bill passed. In New York, none of it applies; a City of Yes homeowner is still fighting to prove the lot qualifies at all, a bar the Regional Plan Association put near 12 percent of one- and two-family lots. Two of our markets already did what California just voted for, and one is nowhere close.

What to watch

The bill is enrolled as of September 1 and now awaits the governor's signature; he has until the fall deadline to sign it, veto it, or let it become law unsigned. If it takes effect, cities will have to update their ordinances or fall back on ministerial approval by default. Watch two things. First, whether your city treats "two detached" as a hard right or buries it in lot-coverage and floor-area rules that kill the second unit without ever saying no. Second, whether an HOA tests the "zoned to allow" language in court, the way a Carlsbad association tested the reach of ADU law when a court ruled, as we reported, that state ADU rules do not automatically override a condo project's recorded declarations. That fight is not settled. AB 956 just moved the line.

If you are weighing whether your lot can hold one detached ADU or two, A-du's permit fee calculator shows what each unit adds to the permit stack before you commit a dollar to design.

Newsom's signature is the next domino, but the real test comes when the more than 400 California cities have to decide whether "two detached ADUs" means yes or means paperwork.

Elsewhere on the ADU beat

• The ADU package cleared alongside a stack of other housing bills as the session closed on August 31, tracked by California YIMBY.
• San Diego's ADU density-bonus amendments are heading to the California Coastal Commission for certification this year, per City of San Diego Development Services.