From Property Feasibility and ADU Design to Permits, Utilities, and Construction, We Help Santa Ana Homeowners Build the Right ADU for Their Lot
Licensed • Insured • Bonded • 15+ Years Experience • Design-Build Experts • Serving Southern California
Have Space for an ADU but Not Sure What You Can Actually Build? We Help Santa Ana Homeowners Figure Out the Right Size, Location, Layout, Permits, Utilities, and Construction Before Breaking Ground.
If you’re thinking about building an ADU, you probably have more questions than answers right now.
That’s where we start.
Before drawing a floor plan, we look at the property you already have—the existing house, garage, available yard, potential ADU location, setbacks, access, utilities, and what you want the new space to accomplish.
Kol & Co. is a licensed, insured, and bonded design-build contractor with 15+ years of residential construction experience, handling ADUs from the initial property evaluation through design, engineering, permits, site work, construction, utilities, kitchen and bathroom installation, inspections, and final completion.
Show us the property and tell us what you want the ADU to do. We’ll start there. Schedule Your ADU Consultation Today!
For the complete ADU projects we typically take on, homeowners should generally plan around:
$200,000–$500,000+
The final cost depends on the ADU size and type, site conditions, foundation, utilities, sewer and electrical work, access, structural requirements, kitchen and bathroom, windows and doors, finishes, engineering, and permits.
That’s why we prefer to talk about the whole project rather than simply quoting a cost per square foot.
An ADU is essentially a small home, which means there is much more involved than framing four walls in the backyard.
We coordinate the documentation needed to turn the concept into a buildable project, which can include:
For a new detached ADU, construction can include:
The ADU needs functioning building systems of its own.
Depending on the project, we coordinate:
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We complete the ADU as an actual living space, including:
Santa Ana’s current regulations include specific standards for ADUs, and the exact requirements depend on the property and proposed unit.
Some important starting points include:
These are planning-level guidelines—not a substitute for evaluating your actual parcel.
State ADU law also changes periodically, which is one reason we verify the applicable requirements when planning the project rather than relying on an old ADU checklist.
For a complete ADU project, homeowners should generally plan for approximately:
12 months including plans, permitting, and construction.
Some projects move faster and more complicated properties can take longer.
Yes. Building or converting space into an ADU in Santa Ana requires City review and permits before construction can begin.
An ADU is a complete dwelling—not simply an extra room—so the plans need to show that the proposed unit meets applicable zoning and building requirements.
Depending on the project, the permit process can involve:
Site and floor plans
Architectural drawings
Structural plans and engineering
Title 24 energy documentation
Plumbing, electrical, and mechanical plans
Utility and sewer information
ADU size, height, and setback compliance
Applicable building and safety requirements
Santa Ana reviews ADU and JADU applications ministerially when the application is complete and the proposed project complies with the City’s requirements.
We visit your Santa Ana property, discuss why you want an ADU, and look at the house, garage, yard, potential building locations, access, and site conditions.
We determine the appropriate type, size, location, and layout based on your goals and the property.
We prepare for construction by coordinating design, engineering, applicable documentation, and permitting.
Our team coordinates site work, foundation, framing, roofing, windows, utilities, plumbing, electrical, HVAC, kitchen, bathroom, and finishes.
We coordinate the construction stages through required inspections, finish the remaining details, and walk the completed ADU with you.
We work with homeowners throughout Floral Park, West Floral Park, Park Santiago, Washington Square, Wilshire Square, Heninger Park, French Park, Fisher Park, Morrison Park, and surrounding Santa Ana neighborhoods.
You don’t need to know the exact size, layout, or type of ADU before contacting us.
Show us your Santa Ana property and tell us what you want the additional space to do—whether it’s for family, guests, rental income, or more living space.
We’ll look at the lot, existing home or garage, available space, access, and potential project scope and help you understand what may be possible and what the next steps look like.
For the complete ADU projects we typically take on, homeowners should generally plan for approximately $200,000–$500,000+. Size, ADU type, site conditions, utilities, foundation work, structural requirements, kitchen and bathroom selections, and finishes all affect the final cost.
For planning purposes, we recommend allowing approximately 12 months for the overall project, including design, engineering, permits, construction, and inspections. The actual schedule depends on the property and project complexity.
Santa Ana’s current regulations allow ADUs up to 1,000 square feet in certain configurations. The actual size available to your project depends on the ADU type, existing home, lot, setbacks, and other applicable requirements.
Current Santa Ana standards generally provide for 4-foot side and rear setbacks for ADUs, although the exact requirements depend on the property, ADU type, existing structures, and applicable provisions.
Under Santa Ana’s current ADU ordinance, detached ADUs can be up to 20 feet in height, subject to applicable project requirements.
Yes. As a design-build contractor, Kol & Co. can coordinate the ADU from property evaluation and design through engineering, permits, construction, inspections, and completion.
