ADU Design & Construction
Create a custom accessory dwelling unit for family, guests, work, or rental potential—with one coordinated team managing design, plans, permits, construction, and final inspection.
Licensed California contractor • CSLB #1048623 • Design-build service from concept through completion
An ADU Planned Around Your Property
A successful ADU begins with a practical plan for your property. Size, access, privacy, utilities, structure, daylight, storage, and long-term use all shape the right design.
Royalty Builders reviews your site, priorities, budget, and local requirements before recommending the right path from concept through completion.
01
Detached ADU
Create a separate backyard residence with an efficient layout, private entrance, full living facilities, and finishes that complement the main home.
02
Attached ADU
Expand the existing home with an independent unit designed for privacy, natural flow, and practical utility connections.
03
Garage Conversion ADU
Transform an existing garage into a code-compliant living unit, with an addition when the current footprint needs more space.
One Team for the Entire ADU
01
Site Review
We document the lot, access, existing structures, utilities, and project goals.
02
Design & Budget
We develop the floor plan, scope, finish direction, and a realistic project budget.
03
Permits & Build
Our team coordinates plans, permits, construction, and required inspections.
04
Completion
We complete the finishes, final walkthrough, required inspections, and project closeout.
ADU Planning, Permits & Construction
ADU feasibility depends on the property, proposed size and use, access, utilities, zoning, and site conditions. The right plan coordinates architecture, engineering, energy requirements, and construction details from the start.
We help coordinate plans, permit documentation, construction, and required inspections for the approved scope. Property-specific requirements are confirmed with the applicable local agencies.
Eligibility, scope, cost, schedule, and approval requirements are property-specific. Final requirements are determined by the applicable agencies.
What We Evaluate
- Lot layout, existing structures, grading, and drainage
- Setbacks, access, privacy, daylight, and outdoor space
- Electrical capacity, plumbing routes, HVAC, and insulation
- Fire separation, egress, energy, and life-safety requirements
- Kitchen, bathroom, laundry, storage, and accessibility needs
- Finish selections that complement the main residence
Considering a garage conversion? View our garage conversion design-build approach or schedule a consultation for your property.
Clear Communication. Thoughtful Construction.
Our design-build approach keeps planning and construction coordinated and gives you one accountable team from the first site visit through completion.
We also handle whole-home remodeling, additions, kitchens, and bathrooms, so the ADU can be coordinated with a larger home improvement plan.
Frequently Asked Questions
Can every property support an ADU?
Not every site supports the same ADU type or size. Feasibility depends on lot conditions, access, utilities, existing structures, local requirements, and the intended use.
What types of ADUs do you build?
We design and build detached ADUs, attached ADUs, garage-conversion ADUs, and property-specific combinations where feasible.
How long does an ADU project take?
The schedule varies with design complexity, engineering, permit review, site conditions, selections, and construction scope. We establish a project-specific timeline after evaluation.
Do you handle design and permits?
Yes. Royalty Builders offers coordinated design-build service and helps manage the plan and permit process for the approved scope.
Can you coordinate the ADU with remodeling the main house?
Yes. We can coordinate the ADU with kitchen, bathroom, addition, or whole-home remodeling work.
Start With a Practical ADU Site Evaluation
Tell us how you want to use the space. We’ll help you understand the ADU design-build options and the right next step for your property.