Two Detached ADUs in Livermore (AB 956, 2027)
Plan Two ADUs in Livermore: Free Site Assessment
Livermore ADU rules today (2026)
From January 1, 2027, state law (AB 956) requires cities, including Livermore, to approve up to two detached ADUs on a lot with a single-family home. In late 2025 the state housing department told Livermore that the ADU ordinance it has on file for the city is from 2018. Here is what we know and how we approach a Livermore project.
- Units allowed now: no Livermore rule we found allows two new detached ADUs on a single-family lot today.
- Setbacks: the city’s Planning FAQ says ADUs follow its accessory structure setback guidelines. Lots in a PD or PUD zone must check with a city planner.
- Pre-approved plans: Livermore pre-approves ADU plans that can be used citywide, with expedited review.
- ADU Accelerator: the city also runs an ADU Accelerator Program.
- Current standards: Livermore keeps its detailed ADU standards in a separate handout. We confirm sizes, height and parking with the city for each project rather than rely on summaries.
State review of Livermore's ADU rules
On October 8, 2025, HCD sent Livermore a technical assistance letter. It said the most recent Livermore ADU ordinance on file is from 2018, that it may be outdated, and that an ordinance that does not comply with state law is “null and void.” In that case, state ADU standards apply. The city’s response was due November 7, 2025. In plain terms: where Livermore’s local rules conflict with state ADU law, the state standards control. Where local rules are stricter than state law, state law applies.
Recent Axiom work
Professional photos from a recent Axiom Renovation full remodel and addition in Los Gatos.
What changes on January 1, 2027
AB 956 raises the number of detached ADUs Livermore must approve on a single-family lot from one to two, both new construction. Each may be limited to 800 sq ft of living space, local height limits can still apply, and side and rear setbacks can be no more than 4 ft. Where two detached ADUs are built, a JADU on the same lot does not have to be approved. The law also includes protections for owners in homeowners associations.
For Livermore, this means a second detached unit becomes possible on a single-family lot. Livermore will need to update its ADU rules, and we will confirm the current requirements as it does.
Planning two detached ADUs on a Livermore lot
- PD and PUD lots: many neighborhoods have their own setbacks. We check them with a planner before design.
- Design standards: we confirm which city design standards apply to each unit.
- Electrical: two ADUs usually need a load calculation and often a service upgrade.
- Pre-approved plans: a city pre-approved plan can shorten review if it fits the lot and the size limits that apply in 2027.
Building ADUs in Livermore with Axiom
See our Livermore ADU builder page and our Livermore service area, read the AB 956 overview, or compare neighboring Pleasanton and Dublin.
Process
Our ADU Process
Step 1
Initial Consultation
We begin with a thorough initial consultation to understand your needs, assess your space, and discuss your vision, budget, and timeline.
Step 2
Planning and Design
At Axiom Renovation, we understand that the planning and design phase of an ADU project is crucial to its success. Our dedicated project managers will work closely with you to understand your goals, design ideas and budget for the project.
Step 3
Material Selection
We guide you through selecting high-quality materials that fit your design and budget, ensuring durability and aesthetic appeal.
Step 4
Demolition and Preparation
Careful demolition and preparation work are performed to ready the space for construction, minimizing disruptions and ensuring a clean work environment.
Step 5
Construction and Installation
Our skilled craftsmen handle the construction phase, including obtaining permits, scheduling appointments, and the actual construction and installation with precision, building the new space according to the approved design.
Step 6
Electrical and Plumbing Work
Licensed professionals conduct all electrical and plumbing work, ensuring everything is up to code and seamlessly integrated into the new ADU.
Step 7
Painting and Finishing
We pay close attention to detail during the painting and finishing stage, ensuring all surfaces are properly prepared and beautifully finished.
Step 8
Fixture and Appliance Installation
We expertly install all fixtures and appliances, ensuring they function correctly and fit perfectly with the overall design.
Step 9
Final Touches and Clean-Up
Final touches are added, and a thorough clean-up is performed, leaving your new space pristine and ready for use.
Step 10
Final Walkthrough and Client Satisfaction
We conduct a final walkthrough with you to ensure every detail meets your expectations and address any remaining concerns, ensuring your complete satisfaction.
Livermore Two-ADU FAQ
Can I build two detached ADUs in Livermore?
From January 1, 2027, AB 956 requires Livermore to approve up to two detached, new-construction ADUs on a single-family lot that meets objective standards.
How large can each ADU be in Livermore under AB 956?
AB 956 lets the city limit each of two detached ADUs to 800 sq ft of living space. We confirm Livermore’s current size rules with the city for each project.
What did HCD say about Livermore’s ADU ordinance?
In October 2025, HCD said the most recent Livermore ADU ordinance on file is from 2018 and may be outdated. If a local ordinance does not comply, it is null and void and state ADU standards apply.
Does Livermore have pre-approved ADU plans?
Yes. Livermore pre-approves ADU plans that can be used anywhere in the city, with expedited review.
My Livermore home is in a PD or PUD zone. Does that matter?
Yes. The city says ADUs on PD or PUD lots should be reviewed with a planner, because those zones can set their own setbacks.
Who builds two-ADU projects in Livermore?
Axiom Renovation designs, permits and builds ADUs in Livermore and is planning two-unit projects for 2027. Call 408-702-2022, Monday to Friday, 9 am to 5 pm.
Sources: AB 956 (Quirk-Silva), signed September 29, 2026, effective January 1, 2027, as summarized by Brownstein Hyatt Farber Schreck and California YIMBY; Livermore ADU page; Livermore pre-approved ADUs; HCD letter, October 8, 2025. This page is general information, not legal advice. Local rules change; we confirm current requirements with the city for every project.