LA ADU Rules 2026 — AB 1033, SB 9, SB 543, AB 130
California's ADU rules have shifted five times in the last three years. Here's the 2026 state: what size, how many, who approves, how fast, what it costs to get a permit.
SB 543 (effective 2025) — the fee killer
Eliminates ALL development impact fees for ADUs and JADUs statewide.
Saves LA homeowners $5,000–$30,000 per project.
Mandates 15-business-day completeness check on ADU applications.
Caps JADU interior size at 500 sqft.
AB 130 (2025) — the timeline mandate
Permitting agency must acknowledge submittal within 30 days.
Full decision within 60 days of complete application.
If the agency misses the 60-day deadline, the application is deemed approved by law.
AB 1033 — ADU condo sales pathway
Cities may opt in to allow ADUs to be sold as separate condominium units on the same parcel.
Los Angeles has NOT opted in as of 2026 — so LA ADUs cannot be sold separately from the main house.
Glendale, West Hollywood, and several other LA-area cities HAVE opted in — check before you build.
SB 9 / HOME Act — lot splits
Allows up to four units total on a single-family parcel via lot split + duplex.
Ministerial approval — no public hearings, no discretionary review.
Limitations: not in HPOZ, not in Very High Fire Hazard Severity Zone (with exceptions), not on non-urban parcels.
Owner-occupancy requirement for 3 years after split.
City-of-LA ADU specifics
Max detached ADU size: 1,200 sqft (city-of-LA interprets state cap for single-family parcels).
Max height: 16 ft single-story, 18 ft two-story, 25 ft for two-story on parcels over 12,000 sqft.
Side and rear setbacks: 4 ft minimum.
Parking: waived for ADUs within ½ mile of transit (which covers most of LA), plus several other waiver conditions.
Solar: new detached ADUs require Title 24 solar PV unless exempt by orientation or shading.
LADBS Standard Plan Program
Pre-approved ADU designs that skip structural plan-check. Cuts permit time from 8–12 weeks to 4–6 weeks.
Available designs range from 600 to 1,200 sqft, single-story and two-story.
Limited customization (exterior finish choices, window placements) but saves weeks.
Still have questions?
Ask Baily — pre-seeded for this topic.
LA ADU Rules 2026 — scoped by Baily.
Who is Baily?
Baily is named after Francis Baily — an English stockbroker who retired at 51, became an astronomer, and in 1836 described something on the edge of a solar eclipse that nobody had properly articulated before: a string of bright beads of sunlight breaking through the valleys along the moon's rim.
He wasn't the first to see them. Edmond Halley saw them in 1715 and barely noticed. Baily's contribution was clarity — describing exactly what was happening, in plain language, so vividly that the whole field of astronomy paid attention. The phenomenon is still called Baily's beads.
That's what we wanted our AI to do. Every inbound call and text has signal in it — a homeowner's real question, a timeline, a budget, a hesitation that means “yes but.” Baily listens to every one, 24/7, and finds the beads of light.
Baily was a businessman before he was a scientist. That's our vibe too.