ADU Contractors in San Diego
Complete design-build solutions for Accessory Dwelling Units. From architectural drawings to finished construction — one licensed contractor handles it all.
Building an Accessory Dwelling Unit (ADU) is one of the smartest investments a San Diego homeowner can make. Whether you want a rental unit for passive income, an in-law suite for family, or a home office detached from the main house, Subworkit Contracting handles the entire process — design, engineering, permits, and construction — as your single-source ADU contractor.
California's ADU-friendly legislation has made it easier than ever to add a secondary dwelling to your property. The City of San Diego and surrounding jurisdictions have streamlined their ADU approval processes, and our team navigates these regulations daily. We understand the zoning requirements, setback rules, parking exemptions, and utility connection standards for each city we serve.
Our ADU construction process begins with a thorough site evaluation and feasibility assessment. We'll determine what type of ADU — detached, attached, garage conversion, or Junior ADU (JADU) — works best for your property and goals. Our in-house architectural team then creates custom plans that maximize your space while meeting all Title 24 energy requirements, structural engineering standards, and local building codes.
Cost transparency is a cornerstone of our ADU services. We provide detailed, itemized estimates that break down every phase of the project — from demolition and foundation work to framing, plumbing, electrical, HVAC, and finishes. There are no surprises or change orders that catch you off guard. Most ADU projects take 4–6 months after permit approval, and we keep you informed with regular progress updates throughout the build.
What We Offer
Custom ADU Design
Architectural drawings tailored to your property and lifestyle. Studio, 1-bedroom, and 2-bedroom layouts with modern finishes and efficient floor plans.
Engineering & Title 24
Structural engineering, energy calculations, Title 24 compliance reports, and soils reports — all coordinated by our team.
Permit Filing & Approvals
Complete permit application handling, plan check responses, city corrections, and inspection scheduling. We manage the bureaucracy so you don't have to.
Ground-Up Construction
Foundation, framing, roofing, plumbing, electrical, HVAC, insulation, drywall, flooring, and finish work — all performed by our licensed crews.
Garage Conversions
Convert your existing garage into a fully permitted ADU with proper insulation, utility connections, windows, and finishes.
Junior ADU (JADU)
Create a JADU of up to 500 sq ft within your existing home. A cost-effective way to add rental income or family living space.
Why Choose Subworkit as Your ADU Contractor?
One-Stop Shop — Design, engineering, permits, and construction all handled by our team
Licensed General Contractor — CA License #945572 with full insurance coverage
Local ADU Expertise — Deep knowledge of city-specific zoning rules and approval processes
Transparent Pricing — Detailed, itemized estimates with no hidden costs or surprise change orders
Quality Construction — Premium materials, skilled crews, and proper inspections at every phase
Proven Track Record — Successful ADU completions across San Diego County
Our ADU Construction Process
Free Consultation
We evaluate your property, discuss your goals (rental income, family housing, etc.), and determine the best ADU type for your lot.
Design & Engineering
Our architects create custom plans and engineers prepare structural calculations, Title 24, and any required reports.
Permits & Approvals
We submit plans to the city, handle plan check comments and corrections, and schedule all required inspections.
Construction
Our licensed crews build your ADU from foundation to finish — typically 4–6 months after permit approval.
Project Pricing
Most attached ADU additions take 4–6 months to complete after city approval. Budgets typically range from $160,000–$320,000+, depending on project size, materials, and site conditions. Garage conversions start at approximately $100,000–$180,000. We offer detailed, transparent estimates at no cost.
Contact us for a detailed quote tailored to your specific project.
Frequently Asked Questions
How much does it cost to build an ADU in San Diego?
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Most ADU projects range from $160,000–$320,000+ depending on size, site conditions, materials, and finishes. Garage conversions start lower at approximately $100,000–$180,000. We provide detailed, itemized estimates during our free consultation.
How long does it take to build an ADU?
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From design to completion, a typical ADU takes 8–12 months. This includes 2–4 months for design, engineering, and permits, followed by 4–6 months of construction. Timelines vary by city and project complexity.
Do I need a permit to build an ADU?
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Yes, all ADUs in California require building permits. The good news is that state laws have streamlined the process and limited cities' ability to block ADU construction. We handle all permit applications and approvals.
Can I rent out my ADU?
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Yes. California law allows homeowners to rent ADUs at market rates. An ADU in San Diego can generate $1,500–$3,500+ per month in rental income depending on size and location, making it an excellent investment.
What's the difference between an ADU and a JADU?
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An ADU is a separate dwelling unit (detached or attached) up to 1,200 sq ft. A Junior ADU (JADU) is created within your existing home, limited to 500 sq ft, and must share a bathroom or kitchen with the main house. Both can generate rental income.
Free Tool
Estimate Your ADU Contractors Costs Instantly
Use our free construction cost estimator to calculate materials, labor, and total project costs based on real retail pricing.
Try the Free Estimator →Ready to Build Your ADU? Start with a Free Consultation
Let's discuss your property, your goals, and your budget. Contact us today for a no-obligation consultation with experienced ADU contractors in San Diego.
Where We Serve
We build ADUs throughout San Diego County including La Mesa, El Cajon, National City, Chula Vista, La Jolla, Escondido, Oceanside, Carlsbad, Poway, and all surrounding communities. Our team is familiar with ADU regulations in each San Diego jurisdiction.
What Our Clients Say
"This is a very nice company that offered the services I needed. If you are in need of a company that does a clean and professional job, then I highly recommend Bernard and his team!"
— Happy Customer
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