Do You Need an ADU Architect in San Diego? Here’s the Truth
If you’re planning to build an ADU in San Diego, one of the first questions you’ll run into is: do I need to hire a separate architect?
It’s a fair question — and the answer isn’t as simple as yes or no. It depends on the type of ADU you’re building, the complexity of the project, and who you’re working with.
At IL Total Design & Build, we handle architectural design and construction under one roof. That means you don’t have to coordinate between a separate architect and a contractor — we manage everything from initial design through final inspection.
Here’s what you actually need to know.
What Does an ADU Architect Do?
An ADU architect is responsible for producing the construction drawings and plans required to obtain a permit from the City of San Diego. These plans must meet local zoning codes, Title 24 energy compliance requirements, and structural engineering standards.
Specifically, architectural plans for an ADU in San Diego typically include:
- Site plan — showing the location of the new ADU on the property
- Floor plans — room layouts, dimensions, door and window locations
- Elevation drawings — exterior views of all four sides of the structure
- Structural details — foundation type, framing, roof system
- Title 24 energy calculations — required for all new construction in California
- Mechanical, electrical, and plumbing (MEP) plans — where required by the city
Without these documents, the City of San Diego will not issue a building permit — and without a permit, you cannot legally build.
Is a Licensed Architect Required by Law in California?
Not always — and this is where a lot of homeowners get confused.
California law allows licensed contractors with the appropriate CSLB license (Class B General Building Contractor) to prepare and submit plans for certain residential projects without a separate licensed architect. For most standard ADU types — detached ADUs, garage conversions, attached additions, and JADUs — a licensed general contractor with design experience can legally prepare and submit the plans.
A licensed architect is typically required when:
- The project exceeds certain structural complexity thresholds
- The city reviewer requests stamped architectural plans
- The project involves multi-family construction or commercial zoning
- Your lender requires architect-stamped plans for financing
For the majority of residential ADU projects in San Diego, a licensed design-build firm like IL Total Design & Build can handle everything without requiring you to hire a separate architect — while still producing fully permitted, code-compliant plans.
The Problem With Hiring a Separate Architect
Many homeowners assume they need to hire an architect first, get their plans drawn up, and then find a contractor to build it. While that process can work, it comes with some real drawbacks:
It creates unnecessary back-and-forth. When your architect and contractor are separate companies, changes made during construction often require plan revisions — which means going back to the architect, paying for revisions, and potentially resubmitting to the city.
Architects don’t always understand construction costs. A design that looks great on paper can be significantly over budget once a contractor prices it out. When design and construction are handled by the same team, you get real-time cost feedback throughout the design process.
It adds time. Coordinating between two separate firms slows things down. Permitting in San Diego already takes time — you don’t want to add months of back-and-forth to the equation.
It adds cost. Architectural fees for ADU plans in San Diego typically run between $5,000 and $15,000 or more depending on complexity. When you work with a design-build firm, that cost is often bundled into the overall project — and there’s no double billing for coordination.
How IL Total Design & Build Handles It
We’re a licensed design-build firm, which means we handle the full process — from your initial property assessment through construction and final city sign-off.
Here’s how our process works:
1. Free Consultation
We start with a conversation about your property, your goals, and what’s possible under current San Diego ADU regulations. We’ll tell you upfront what type of ADU makes sense for your lot and roughly what it will cost.
2. Design & Drafting
Our in-house design team develops your ADU plans — floor plans, elevations, site plans, and all required documentation for permit submittal.
3. Permit Submittal
We prepare and submit your permit application to the City of San Diego and manage all back-and-forth with the plan checker. This is one of the most time-consuming parts of the process, and having an experienced team handle it makes a significant difference.
4. Construction
Once permits are approved, construction begins. Because we designed the project, our team knows every detail of the plans — no learning curve, no surprises.
5. Final Inspection & Close-out
We manage all city inspections throughout construction and coordinate the final sign-off so your ADU is fully permitted and ready to use.
San Diego ADU Regulations You Should Know
Before you hire anyone — architect or design-build firm — it helps to understand the basics of what’s allowed in San Diego.
ADU size limits:
- Detached ADUs: up to 1,200 sq ft (or 50% of the primary dwelling, whichever is less)
- Attached ADUs: up to 50% of the primary dwelling’s square footage
- JADUs (Junior ADUs): up to 500 sq ft, created within the existing home footprint
- Garage conversions: typically limited to the existing garage footprint
Setbacks:
- New detached ADUs require a minimum 4-foot rear and side setback
- Front yard setbacks generally follow existing zoning
Parking:
- In many cases, ADUs in San Diego do not require additional parking — especially if the property is within ½ mile of public transit
Owner-occupancy:
- California law currently does not require owner-occupancy for ADUs on most properties through 2025 (regulations may change — contact us for current rules)
These rules change frequently. The best way to know exactly what’s possible on your specific property is to schedule a free consultation with our team.
Frequently Asked Questions
Do I need a permit to build an ADU in San Diego?
Yes. All ADUs in San Diego — including garage conversions — require a building permit from the City of San Diego Development Services Department. Unpermitted ADUs create significant legal and financial risk when it comes time to sell or refinance.
How long does it take to permit an ADU in San Diego?
Permit timelines vary. The City of San Diego has made improvements to its ADU permitting process in recent years, and many projects can be approved within 30–90 days depending on the project type and whether corrections are needed. Our team manages this process for you.
Can I convert my garage into an ADU without an architect?
In most cases, yes. Garage conversions are among the simplest ADU types to permit and build, and a licensed design-build firm can handle the plans and permit submittal without a separate architect.
What’s the difference between a JADU and an ADU?
A Junior ADU (JADU) is created entirely within the existing footprint of the primary home — typically from a bedroom or other interior space. It’s limited to 500 sq ft and must include its own entrance. A standard ADU can be detached, attached, or converted from a garage, and can be up to 1,200 sq ft.
Does IL Total Design handle the permit process?
Yes. We manage the full permit submittal, including all required plan documents, city correspondence, and inspection coordination.
Ready to Find Out What’s Possible on Your Property?
The best way to answer the question “do I need an architect?” is to start with a conversation. We’ll review your property, explain your options, and give you a clear picture of what the process looks like — at no cost.
IL Total Design & Build
CA License #1058676
San Diego, CA | (619) 404-0125 | Contact@ILTotalDesign.com
