Updated October 2026
AB 1033 lets a city allow an ADU to be sold separately from the main house, as a condominium. It is optional: nothing changes on your lot until your city adopts its own ordinance.
The short version
- Signed October 11, 2023, in effect since January 1, 2024.
- Opt-in only. San Jose was the first city to adopt it, in 2024. Berkeley took up its own ordinance in 2025. Check whether your city has.
- The sale needs a condominium plan that complies with the Subdivision Map Act and local subdivision rules.
- Every lienholder on the property must consent in writing before the condo plan is recorded.
- A safety inspection, notice to utility providers and, in planned developments, written HOA approval are also required.
What it is
Normally an ADU can’t be sold apart from the main house. AB 1033 creates an exception. Once your city opts in, the house and the ADU become two condominium units on one lot, with separate titles and shared obligations for the land, roof, utilities and common areas. It applies to ADUs built under state ADU law. The statute doesn’t require the owner to live on site.
What to watch out for
- Availability. Most cities haven’t opted in. If yours hasn’t, the option doesn’t exist yet.
- Your lender. Written consent from every lienholder is the step that stalls most deals.
- The association. Two owners on one lot need CC&Rs, a budget, insurance and a plan for shared repairs.
- Utilities. Shared meters and sewer laterals complicate separate ownership. Separating them can cost more than the paperwork.
- Buyers. A small condo with a shared yard is a narrow market. Talk to a broker before you design for resale.
A cleaner path for many lots
If the goal is homes you can sell, a small-lot subdivision is often simpler. Under SB 684 (multifamily zones) and SB 1123 (vacant single-family lots), you can create up to 10 fee-simple lots with 60-day ministerial approval. Each buyer owns a house and its land, with no condo plan between neighbors. See SB 684 and SB 1123.
How we use it
We used SB 684 to entitle Motor Complex in Culver City, a four-lot split of a 7,000 sf lot. La Puente Spine (concept) lines ten townhouses along one shared walk. Both are built around separate, sellable homes from day one.
Have a lot in mind?
Send us the address and we’ll tell you what it can hold. Book a free consultation → · Follow @ydsarch on Instagram
