ADU Construction
We specialize in ADU construction—managing design coordination, permits, and construction so your project stays on schedule and stress stays low.
- Licensed & Insured
- Permit-Friendly ADU Builds
- Detached, Attached & Garage Conversions
- Serving Riverside & Orange County
Expert ADU Construction Services with a Focus on Detail & Quality
SouthSTAR Construction is a leading ADU Contractor. Providing professional ADU construction services throughout Riverside County and Orange County, including Corona, Norco, Eastvale, Riverside, and surrounding cities. We build detached ADUs, attached ADUs, garage conversions, and JADUs with a streamlined, permit-conscious approach.
ADU COST BREAKDOWN in California
Every ADU project is unique. The information below is provided to help homeowners understand the typical cost components involved in building an Accessory Dwelling Unit (ADU). Final pricing depends on site conditions, design complexity, utility requirements, material selections, and local permitting jurisdiction.
*Cost ranges shown are estimates only and do not constitute a formal quote.*
Project Plans & Design
Typical Range: $4,500 – $15,000
Architectural plans and engineering are required to obtain permits and ensure the ADU complies with local building codes. Design costs vary based on layout complexity, structural requirements, and the overall scope of the project.
City Permits & Plan Check Fees
Typical Range: $3,500 – $20,000
Permit and plan check fees are determined by the local city or jurisdiction and are typically paid at the time of plan submittal. These fees vary based on ADU size, location, and municipal requirements.
Utility Connections & Site Work
Typical Range: $5,000 - $25,000
Utility connections such as water, sewer, electrical, gas, and fire sprinklers depend on existing infrastructure and site conditions. These costs vary by property and are evaluated during the planning phase.
ADU Construction Costs
Typical Range: $250 – $450 per SQFT
Construction costs depend on several factors, including:
- ADU size and layout
- Finish level and material selections
- Structural and foundation requirements
- Site access and construction logistics
Our Approach to ADU Pricing
The most accurate way to understand ADU pricing is to review your property, city requirements, and project goals. We’ll help you confirm feasibility, define scope, and outline the next steps toward building your ADU.
Get a Realistic ADU Cost for Your Property
Our pricing reflects professional project management, permit-conscious planning, and quality craftsmanship built to last. We focus on well-executed ADUs designed for long-term value—not low-cost, shortcut-driven construction.
Why You Should Build an ADU
- Additional Rental Income
Generate monthly income by renting your ADU long-term or using it as flexible housing for extended stays. - Multigenerational Living
Create a private, comfortable living space for parents, adult children, or guests—while maintaining independence and privacy. - Increase Property Value
ADUs add functional square footage and versatility, often increasing overall property value and market appeal. - More Affordable Than Buying or Expanding
Building an ADU can be more cost-effective than purchasing a new home or completing a large-scale addition. - Flexible Living Space
Use your ADU as a home office, guest suite, studio, or future rental—allowing your needs to evolve over time. - Age-in-Place Solutions
Provide a safe, independent living option that allows loved ones to stay close while maintaining autonomy.
ADUs are a popular solution throughout Riverside County and Orange County for homeowners seeking flexible, long-term housing options.
Not sure if an ADU makes sense for your property? We can help you evaluate your options.
ADU Guidelines & Resources: California Department of Housing and Community Development
ADU CONSTRUCTION SERVICES
At SouthSTAR Construction, we provide end-to-end ADU construction services, managing every phase of the process from initial planning through final inspection. Our approach is designed to deliver a smooth, organized, and predictable experience for homeowners.
Our ADU Services Include:
ADU Planning & Feasibility
Site evaluation, zoning review, and early planning to confirm what’s possible on your property.
Design & Permit Coordination
Collaboration with designers and engineers, permit preparation, and coordination with local jurisdictions.
Full ADU Construction
Detached ADUs, attached ADUs, garage conversions, and JADUs built with quality materials and disciplined project management.
Utilities & Site Integration
Coordination of electrical, plumbing, sewer, water, gas, and fire sprinkler connections as required.
Interior & Exterior Finishes
Complete build-out including kitchens, bathrooms, flooring, cabinetry, windows, doors, and exterior finishes.
Project Management & Inspections
Scheduling, trade coordination, inspections, and final walkthrough—handled start to finish by our team.
We specialize in complete ADU builds, not partial scopes or piecemeal construction.
Start Your ADU Consultation
We specialize in full ADU construction projects. Submissions are reviewed within 1–2 business days.
ADU Construction Service Areas:
Riverside County ADU Service Areas
Corona, Norco, Eastvale, Riverside, Chino, Chino Hills, Ontario, Jurupa Valley, Moreno Valley, Temecula, Murrieta, and surrounding communities.
Orange County ADU Service Areas
Anaheim, Orange, Yorba Linda, Fullerton, Brea, Placentia, Garden Grove, Santa Ana, Irvine, Huntington Beach, and surrounding communities.