Building an ADU in Santa Ana
Santa Ana is a city of established neighborhoods, compact lots, and homes with plenty of potential to grow. Lamarc Prime Builders helps Santa Ana homeowners add an ADU for rental income, aging parents, adult children, or extra space of their own. Santa Ana allows detached ADUs up to two stories, and the city has its own pre-approved ADU plans, so there are more options here than many homeowners expect. We check your lot, your zoning, and whether you are in one of the city’s historic districts, then design and build the project from permits through final inspection.
ADU Services Available in Santa Ana, CA
We provide end-to-end ADU support in Santa Ana, including planning, permitting coordination, and construction. Whether you’re building a new unit or converting existing space, we help you choose a practical design that aligns with city requirements and your long-term goals.
✅ Detached & Attached ADUs
✅ Garage Conversion ADUs
✅ Junior ADUs (JADUs)
✅ ADU Planning & Design Coordination
✅ Permits, Plan Submittals & City Revisions
✅ Construction, Inspections & Final Completion
Not sure what your property allows? Start with a free site evaluation to get clear next steps.
ADU Rules in Santa Ana
ADUs allowed per lot
1 ADU + 1 JADU on a single-family lot
Max detached ADU size
Up to 1,000 sq ft
Max attached ADU size
Up to 1,000 sq ft or 50% of the main home, whichever is less
Max JADU size
Up to 500 sq ft
Max height (detached)
20 ft or two stories
Two-story ADU
Detached ADUs can be two stories; attached ADUs follow your zone
Setbacks
4 ft side and rear
Space between buildings
We confirm for your lot
Parking
1 space for new ADUs; none for studios, near transit, in historic districts, or for conversions
Owner occupancy
Not required for an ADU; JADU requires the owner to live on site
Short-term rental (Airbnb)
30-day minimum; no vacation rentals
Impact fees
Application, permit, and impact fees can apply; we plan for them early
Pre-approved plans
Yes: city plans (not in flood zones or three historic districts)
Permit review
Planning, Building & Safety, and Public Works review
Approval timeline
60 days after a complete application
Local insight
Santa Ana allows detached ADUs up to 20 ft or two stories. The city's pre-approved plans can't be used in flood zones or in the French Park, Downtown, and Floral Park historic districts.
How ADU Permitting Works in Santa Ana
Santa Ana’s ADU rules are in Section 41-194 of its zoning code, and your application is reviewed by Planning, Building and Safety, and the Public Works Agency. Every new ADU needs its own address, which you request from the Planning Division with a brief project description and a site plan before you submit plans. Under state law, the city must approve or deny a complete application within 60 days. Application review, permit, and development impact fees can apply, so we help you plan for them early.
Property feasibility review
Review zoning, lot conditions, access, utilities, and applicable ADU requirements.
ADU design and preparation
Prepare the site plan, architectural drawings, engineering, and required supporting documents.
City plan review and approvals
Submit the application, coordinate with city departments, and respond to plan-check corrections.
Permit issuance and construction
After approval and permit issuance, proceed with construction and required inspections.
FAQs
Can I build a two-story ADU in Santa Ana?
Possibly. The city allows detached ADUs up to 20 ft or two stories, which gives you more design options than many nearby cities. Attached ADUs follow your zone’s height limit. Setbacks and lot size still decide what fits, so we review your lot first.
Can I use Santa Ana’s pre-approved ADU plans?
If your property is a single-family lot outside Flood Zone A or AE and outside the French Park, Downtown, and Floral Park historic districts, you may qualify. Pre-approved plans can be reviewed by Planning and Building at the same time, which can save time.
Do I need parking for an ADU in Santa Ana?
Often not. No space is required within half a mile of transit, for ADUs created inside an existing building, in a historic district, or for studios, among other cases. Otherwise one space is required for a newly built ADU.
Can I rent my Santa Ana ADU on Airbnb?
No. ADUs and JADUs can be rented for 30 days or more but not as short-term vacation rentals.
Do I have to live on the property to build an ADU in Santa Ana?
No. The city has no owner-occupancy requirement for ADUs. A JADU does require the owner to live in the home or the JADU.
How long does it take to get an ADU permit in Santa Ana?
Once your application is complete, state law gives the city 60 days to approve or deny it. Pre-approved plan projects can be reviewed by Planning and Building at the same time, and the city responds to electronic plan check requests within about three business days.
