How Much Does It Cost to Convert a Garage to ADU in San Diego?
Converting your garage into an Accessory Dwelling Unit (ADU) has become one of the smartest home improvement decisions San Diego homeowners can make in 2025. With California’s streamlined ADU regulations and San Diego’s housing shortage driving rental prices higher, transforming your unused garage space into a functional living unit offers incredible value. But what’s the real investment required for this transformation?
At MEE Builders, as a family-owned San Diego construction company founded by Yaron Gauzner, we’ve guided countless homeowners through successful garage conversions with our personalized, hands-on approach. Let’s break down the actual costs you’ll encounter when converting your garage into a legal ADU in San Diego.
What Is a Garage ADU Conversion?
A garage ADU conversion transforms your existing garage into a complete living space with its own kitchen, bathroom, bedroom, and living areas. Whether you call it a granny flat, in-law suite, or rental unit, this secondary dwelling remains part of your property while functioning as an independent living space. The major advantage? You’re working with an existing structure, which typically costs significantly less than building a new detached ADU from the ground up.
San Diego Garage Conversion Costs: The Complete Picture
Overall Investment Range
In San Diego, garage to ADU conversions typically cost between $65,000 to $130,000 for a standard single-car garage conversion (approximately 240-400 square feet). Two-car garage conversions (400-650 square feet) generally range from $95,000 to $180,000. These ranges reflect San Diego’s specific market conditions, labor costs, and regulatory requirements.
Detailed Cost Breakdown
Design and Architectural Services: $3,500 – $9,000
- Architectural drawings and space planning
- Structural engineering evaluation
- Title 24 energy compliance calculations
- Site assessments and surveys
Permits and City Fees: $3,000 – $8,500
- Building permit fees
- Plan check and review fees
- School district fees
- Sewer and water connection fees
- Development impact fees (varies by neighborhood)
- Coastal Commission review (if applicable)
Construction Costs: $50,000 – $115,000Here’s where most of your budget goes:
- Foundation work and seismic retrofitting: $4,000 – $10,000
- Framing modifications and insulation: $9,000 – $16,000
- Electrical systems and panel upgrades: $6,000 – $12,000
- Plumbing rough-in and fixtures: $7,000 – $14,000
- HVAC installation (mini-split systems): $4,000 – $8,000
- Kitchen build-out: $10,000 – $22,000
- Bathroom construction: $7,000 – $16,000
- Flooring installation: $3,500 – $9,000
- Windows and exterior doors: $3,500 – $8,000
- Drywall, painting, and finishes: $6,000 – $16,000
Additional Expenses: $6,000 – $25,000
- Utility trenching and connections
- Driveway modifications or parking solutions
- Landscaping and exterior improvements
- Solar panel relocation (if needed)
- Alley improvements (for alley-access garages)
San Diego-Specific Factors Affecting Your Costs
Neighborhood and Location
Your specific San Diego neighborhood impacts costs significantly. Coastal areas like La Jolla or Del Mar may require additional Coastal Commission approvals. Historic districts like Bankers Hill or Mission Hills might need design review. Meanwhile, areas like Clairemont or Mira Mesa typically have more straightforward approval processes.
Climate Considerations
San Diego’s mild climate can work in your favor. You might save on insulation costs compared to other regions, and many garage conversions can succeed with efficient mini-split systems rather than full HVAC installations. However, proper ventilation and moisture control remain essential, especially in coastal areas.
Existing Garage Condition
San Diego homes span many decades, from 1920s craftsmans to modern builds. Older garages, particularly those built before current seismic standards, may require substantial structural upgrades. Pre-1970s garages often need complete electrical system replacements to meet current codes.
Parking Requirements
San Diego’s parking replacement rules vary by neighborhood. Some areas require you to maintain the same number of parking spaces, which might mean creating a carport or expanding your driveway. This can add $5,000-$15,000 to your project.
Utility Connections
If your garage sits far from your main home’s utility connections, trenching costs in San Diego’s varied terrain (from canyon lots to flat mesa tops) can range from $3,000 to $12,000.
Smart Ways to Control Costs
Choose the Right ContractorWorking with an experienced, family-owned company like MEE Builders means personalized attention to your budget. We collaborate closely with you to find cost-effective solutions without compromising quality. Our established relationships with suppliers and subcontractors often result in better pricing.
Optimize Your LayoutStrategic design saves money. Placing plumbing fixtures near existing water lines, keeping the kitchen compact but functional, and using the existing garage door opening for windows can reduce costs substantially.
Phase Your Project WiselyWhile it’s tempting to add every upgrade immediately, consider completing the basic conversion first, then adding premium finishes or solar panels later when budget allows.
Maintain Existing StructureKeeping the existing slab, walls, and roof structure intact (when possible) saves thousands compared to major structural modifications.
Return on Investment in San Diego
The financial benefits of garage ADU conversions in San Diego are compelling:
- Rental Income: San Diego garage ADUs typically rent for $1,800-$3,000 monthly, depending on size, location, and amenities
- Property Value Increase: Well-executed ADUs add 25-35% to your property value
- Multigenerational Living: Provides flexible space for aging parents or adult children
- Home Office Potential: Creates dedicated workspace as remote work continues
With average rents, many homeowners see their investment returned within 4-7 years through rental income alone.
Navigating San Diego’s ADU Regulations
San Diego has been progressive in streamlining ADU approvals, but the process still requires expertise. The city offers pre-approved ADU plans that can reduce design costs and approval time. However, these rarely work perfectly for garage conversions without modifications.
At MEE Builders, we handle the entire permit process, from initial planning department consultation to final inspection sign-off. Our experience with San Diego’s building department helps avoid common pitfalls that delay projects or increase costs.
Financing Your San Diego Garage Conversion
Multiple financing options exist for San Diego homeowners:
- Home equity lines of credit (HELOC)
- Cash-out refinancing
- Construction loans
- CalHFA ADU Grant Program (up to $40,000 for income-qualified homeowners)
- San Diego Housing Commission programs
- Credit union construction loans
The MEE Builders Difference
As a smaller, family-owned company, MEE Builders offers something unique in San Diego’s construction market: genuine personal service combined with professional expertise. Yaron Gauzner personally oversees each project, ensuring:
- Transparent pricing with no hidden costs
- Close collaboration throughout your project
- Solutions tailored to your specific needs and budget
- Quality craftsmanship that stands the test of time
Common Mistakes That Increase Costs
Avoid these costly errors:
- Starting construction without permits (legalization costs can double your budget)
- Choosing the cheapest contractor without checking credentials
- Changing plans mid-construction
- Ignoring drainage and grading issues
- Underestimating electrical panel upgrade needs
Your Garage Conversion Timeline
Understanding the timeline helps budget for carrying costs:
- Initial Consultation: 1 week
- Design Development: 2-3 weeks
- Permit Approval: 4-8 weeks (varies by complexity)
- Construction: 12-16 weeks
- Final Inspections: 1-2 weeks
Total timeline: 5-7 months from start to move-in ready
Making the Decision: Is It Worth It?
For most San Diego homeowners, the answer is a resounding yes. Whether you’re looking to help with mortgage payments, create space for family, or build long-term wealth, garage ADU conversions offer exceptional value. The key is working with experienced professionals who understand both construction excellence and San Diego’s unique requirements.
Ready to Transform Your Garage?
Converting your garage to an ADU is more than just a construction project—it’s an investment in your family’s future and financial security. While costs typically range from $65,000 to $180,000, the long-term benefits far outweigh the initial investment when the project is executed properly.
At MEE Builders, we bring years of San Diego-specific experience combined with the personalized attention only a family-owned company can provide. We’ll guide you through every step, from initial concept to final inspection, ensuring your project stays on budget while exceeding your expectations.
Ready to explore your garage’s potential? Contact MEE Builders today at (858) 330-3173 to schedule your consultation. Let’s work together to create a beautiful, functional ADU that enhances your property and enriches your life.
