ADU Cost Calculator

Get an instant estimate for your San Diego ADU project. Detached, attached, or garage conversion.

California ADU Specialist

2026 Prices

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ADU Cost Estimate

Quick planning numbers for San Diego ADU projects - from garage conversions to fully detached units.

Based on recent projects in San Diego County with permits and a small contingency included.

ADU Types Explained

Detached ADU: Standalone unit separate from main home
Attached ADU: Addition connected to existing home
Garage Conversion: Converting existing garage to living space

California law allows ADUs up to 1,200 sq ft on most residential lots. Permits typically take 60-90 days in San Diego.

Project City

ADU Size (sq ft)

CA allows up to 1,200 sq ft

ADU Type

Bedrooms

Finish Level

Include Extras

Separate utilities Full kitchen Washer/dryer hookups Premium finishes

ADU Cost Ranges in San Diego (2026)

ADU costs vary significantly by type, finishes, and neighborhood. Here are typical ranges:

Garage Conversion

$120K - $180K

Attached ADU

$170K - $300K

Detached ADU

$200K - $400K+

What's Included in an ADU?

Foundation: Concrete slab or raised foundation
Framing: Wood frame construction with insulation
Electrical: New panel, wiring, outlets, lighting
Plumbing: Kitchen, bathroom, water heater
HVAC: Mini-split or central heating/cooling
Kitchen: Cabinets, counters, appliances, sink
Bathroom: Shower/tub, toilet, vanity, tile
Finishes: Flooring, drywall, paint, trim
Permits: Building, electrical, plumbing permits

California ADU Benefits

ADUs are a smart investment for San Diego homeowners:

Rental Income: $1,800 - $3,000+/month in San Diego
Property Value: Increases home value 20-30%
Family Housing: Multi-generational living solution
Tax Benefits: Depreciation and expense deductions
No Parking Required: Near transit (within 1/2 mile)
Fast Permits: 60-day approval mandate in CA

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