Two Detached ADUs in Moraga (AB 956, 2027)
Plan Two ADUs in Moraga: Free Site Assessment
Moraga ADU rules today (2026)
From January 1, 2027, state law (AB 956) requires the Town of Moraga to approve up to two detached ADUs on a lot with a single-family home. Moraga rewrote its ADU rules in 2026 with Ordinance No. 321, and its streamlined 800 sq ft detached ADU already matches the size the new law allows.
- Code: Moraga Municipal Code Chapter 8.124, amended by Ordinance No. 321, adopted July 8, 2026 and effective August 7, 2026.
- Units allowed now: one JADU, one converted ADU and one detached ADU on a single-family lot, “or any combination thereof.”
- Streamlined detached ADU: 800 sq ft or less, 16 ft high, 4 ft side and rear setbacks, no parking.
- Standard ADU: 150 to 1,200 sq ft, attached or detached; attached units limited to 50% of the main home but never below 800 sq ft.
- Height: 16 ft for detached ADUs, 18 ft near transit (plus 2 ft for roof pitch).
- JADU: 500 sq ft or less.
- Process: submit by email to the Planning Department. Completeness check in 15 business days; decision within 60 days. Contra Costa County issues the building permit.
- Pre-approved plans: the county PADU program, plus the draft Lamorinda pre-approved ADU prototypes issued July 31, 2026: a 495 sq ft studio, a 510 sq ft one bedroom, and two-bedroom plans of 746 and 796 sq ft.
State review of Moraga's ADU rules
HCD sent Moraga a Letter of Technical Assistance on February 27, 2026. It found the 2021 ordinance likely outdated and out of step with state law changes from 2023 to 2025. From April 6, 2026, the town applied state ADU law directly, and it then adopted Ordinance No. 321. 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, new-construction ADUs the town must approve from one to two. The town may cap each at 800 sq ft of living space and apply height limits; side and rear setbacks can be no more than 4 ft. Where two are built, the town need not approve a JADU. HOA protections also apply.
Moraga allows one detached ADU today. A second detached unit built to the town’s streamlined standard (800 sq ft, 16 ft, 4 ft setbacks) lines up closely with AB 956, and all four draft Lamorinda prototypes are under 800 sq ft. Even with Ordinance No. 321 just adopted, Moraga will need to update its ordinance again, and we confirm current rules with the town as it does.
Planning two detached ADUs on a Moraga lot
- Slopes: a standard ADU’s footprint, including grading and outdoor space, may not have an average slope over 20%, and cut and fill is limited to 200 cubic yards. Streamlined and standard ADUs are exempt from the hillside development permit.
- Trees: historic trees may not be removed for an ADU. Native or orchard trees need 1:1 replacement.
- Fire: Moraga-Orinda Fire District rules set ember-resistant Zone 0 (0 to 5 ft), Zone 1 (5 to 30 ft) and Zone 2 (30 to 100 ft). An ADU needs sprinklers only if the main home has them.
- Sewer: Central San serves Moraga. Two units also need an electrical load calculation and sign-off from your water provider.
Building ADUs in Moraga with Axiom
Axiom Renovation designs, permits and builds ADUs. For two units we start with a site study of fit, utilities and review path. See our Moraga ADU builder page, our Moraga service area page, the AB 956 overview, and guides for nearby Orinda and Lafayette.
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.
Moraga Two-ADU FAQ
Can I build two detached ADUs in Moraga?
From January 1, 2027, AB 956 requires the town to approve up to two detached, new-construction ADUs on a lot with a single-family home, if the project meets objective standards. Today Moraga allows one detached ADU with a converted ADU and a JADU.
How large can each ADU be in Moraga?
Today a streamlined detached ADU is up to 800 sq ft and a standard ADU up to 1,200 sq ft. Under AB 956, the town may limit each of two detached ADUs to 800 sq ft of living space.
What is Moraga Ordinance No. 321?
It is the town’s 2026 rewrite of its ADU chapter, adopted July 8, 2026 and effective August 7, 2026. It sets streamlined, standard and non-ministerial review tracks.
How long does ADU review take in Moraga?
The town checks completeness within 15 business days and approves or denies within 60 calendar days. Contra Costa County then issues the building permit.
Are there pre-approved ADU plans for Moraga?
Draft Lamorinda prototype plans of 495 to 796 sq ft were issued in July 2026 for Moraga, Lafayette and Orinda. The county Pre-Approved ADU program is also available.
Who builds two-ADU projects in Moraga?
Axiom Renovation designs, permits and builds ADUs in Moraga 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. This page is general information, not legal advice. Local rules change; we confirm current requirements with the town for every project.