| Table of Contents |
| 1. How Much to Build an ADU in San Diego? |
1.1 Typical Cost Ranges |
1.2 Additional Cost Factors |
2. Why Costs Have Risen |
| 3. Navigating San Diego’s Permit Environment |
| 4. Top 10 Companies Providing ADU Permits in San Diego |
| 5. Top ADU Permit Builders by Region |
| 6. ADU Permit Fee Waivers in California |
| 7. Is an ADU a Good Investment? |
| 8. FAQ |
Accessory Dwelling Units (ADUs) are transforming how San Diegans add living space and value. Yet questions linger about cost and permitting. Here’s a clear, complete guide to ADU pricing in San Diego, plus insights on top builders and permit fees.
1. How Much to Build an ADU in San Diego?
Average All‑In Cost
| ADU Type | Vertical Build Cost* | All‑In Cost |
|---|---|---|
| 1 BR / 1 BA (500 sq ft) | ~$235K ($475/sq ft) | ~$300K |
| 2 BR / 1 BA (750 sq ft) | ~$275K ($365/sq ft) | ~$350K |
| 2 BR / 2 BA (1000 sq ft) | ~$340K ($340/sq ft) | ~$425K |
| 3 BR / 2 BA (1200 sq ft) | ~$360K ($300/sq ft) | ~$450K |
Typical Cost Ranges
Per sqft build cost: $300–$400 for detached; $200–$300 attached; $150–$250 garage conversions
California statewide range: $125–$300/sq ft—high-end units may reach $600/sq ft
Additional Cost Factors
Design & architecture: $7,500–$15,000
Permit & impact fees: $4,000–$12,000+
Sitework, grading, utilities: $10,000–$30,000
Foundation, roofing, interiors, landscaping, appliances, contingency: ranges from $5K–50K per category
Real-world example: In 2023, a 590 sq ft unit cost $327,756—appliances included .
2. Why Costs Have Risen
Construction across California, including San Diego, rose ~37% from Jan 2021 to Jan 2024. Supply chain, labor shortages, and higher city permit fees further fuel these gains.
3. Navigating San Diego’s Permit Environment
Permit timeframe: May take 3–6 months, with building permit delays common.
Fees: Range $4K–$12K+, depending on unit size, zone, and city department processes.
Waivers & funding:
California grants up to $40,000 pre‑construction cost relief for low‑income households—2024 funds are allocated, future rounds anticipated.
The state’s ADU Permit Fee Waivers (aka Fee Reduction & Encouragement program) can significantly reduce financial burden.
4. Top 10 Companies Providing ADU Permits in San Diego
These firms shine for guiding permit applications and handling paperwork end-to-end:
Fortune ADU Builders – full-service, praised for timeliness and budget
SnapADU – largest ADU-only firm near Oceanside
Coastal Home Builders – strong portfolio, including garage conversions
Earning Construction Group – boutique ADU builds
San Diego ADU Construction – local expert in design + construction
San Diego ADU Solutions – one‑stop shop licensed contractor
7–10. Sherman Builders, Architectural Development, GCC Designs, Go Home Builders – top-rated per Yelp’s June 2025 list.
5. Top ADU Permit Builders by Region
Top ADU Permit Builders in Santa Clara: (statewide waiver eligible; similar cost ranges; notable firms like Reflex Urban.
Top ADU Permit Builders in Chula Vista: Local options include San Diego ADU Solutions, ECO Home Builders, Fausto Construction.
Top ADU Permit Builders in Huntington Beach: Look into Coastal Home Builders and local design-build firms.
Top ADU Permit Builders in Irvine: ADU cost there runs ~$220–$260K; builders like Coastal Home Builders, regional design‑builds adept at zoning and efficient delivery.
6. ADU Permit Fee Waivers in California
California’s ADU funding programs provide:
Up to $40,000 grants toward design, soil, permits; aimed at moderate-income homeowners.
Active in 2024; 2025’s schedule still pending.
Requires proof of income and owner-occupancy in most cases.
7. Is an ADU a Good Investment?
Rental revenue potential: Many owners break even via rent.
Property value increase: Up to a 150% return on ADU investment in San Diego.
Lifestyle benefits: Ideal for in-laws, aging relatives, multi-generational living, or home offices—more accessible and flexible than upsizing
