San Diego ADU Contractor
Free Consultation • Transparent Pricing • Licensed & Insured
OSSC Construction helps San Diego homeowners design and build ADUs that create flexible living space, rental income potential, and long-term property value.
No obligation • 2-minute response
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Your ADU Starts Here
Building an ADU can feel overwhelming without the right team. OSSC Construction helps homeowners understand the process, budget, design options, and construction path so the project moves forward with more clarity.
Start to Finish
A successful ADU project starts with a clear plan. Our process helps you understand what happens next, what decisions need to be made, and how your project moves forward.
We discuss your property, goals, budget, timeline, and how you want the ADU to function.
We review important site details, access, layout opportunities, and project considerations.
We help align the ADU layout, scope, finishes, and pricing direction before construction begins.
We help coordinate the steps needed to prepare your ADU project for construction.
Your ADU is built with steady communication, quality control, and a final walkthrough.
Transparent Planning
Every ADU is different, but clear pricing ranges help you start with realistic expectations. Final pricing depends on size, site conditions, finishes, utilities, and permitting requirements.
Starting Range
$180K - $250K
Starting Range
$250K - $350K
Starting Range
$350K - $500K+
Final pricing depends on project size, site conditions, finish selections, utilities, permits, and overall scope.
Real Projects
See the level of finish, detail, and project planning homeowners can expect from OSSC Construction.
Why Homeowners Choose OSSC
An ADU is a major investment. Our team focuses on helping homeowners understand the process and feel confident from early planning through final walkthrough.
We help define the scope, budget range, and expectations before construction begins.
We understand the importance of site planning, layout, access, and San Diego housing needs.
Your ADU should feel intentional, durable, and professionally finished.
We keep the project moving with a clear process and responsive communication.
Compare Your Options
Clear planning. Better communication. Real accountability.
Common Questions
Here are a few common questions homeowners ask before starting an ADU project in San Diego.
ADU pricing depends on the size, layout, site conditions, utility requirements, finish level, and permit requirements. Many ADU projects start in the low six figures and increase based on complexity. OSSC Construction can help you understand a realistic range for your property.
p>Many San Diego properties may be good candidates for backyard ADUs, but feasibility depends on lot layout, access, setbacks, utilities, and other site-specific details. The best first step is a project consultation and property review.
ADUs can be a strong option for rental income, long-term property value, family housing, or guest space. The right layout and finish level depend on how you plan to use the unit.
Yes. OSSC Construction helps homeowners move from early planning to construction with a more organized process, including scope, layout, pricing conversations, and project execution.
Start by requesting a free ADU quote. We will review your goals, ask a few property questions, and help you understand the next steps.
What Happens Next
Share your goals, timeline, and project details so OSSC Construction can help you understand the best path forward.
Ready to Build?
Tell us what you want to build. OSSC Construction will help you understand your options, next steps, and project path.
What Our Clients Say
We take pride in creating a build experience that feels organized, collaborative, and detail-conscious from the first conversation through final completion.
Sapphire Builders
We build homes and remodel spaces with a focus on quality, proportion, comfort, and the details that shape how people actually live.
