ADU Cost Calculator

Get an instant estimate for your San Diego ADU project. Calculate costs for granny flats, in-law suites, and backyard homes.

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✓ 2025 Prices

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ADU Construction Costs in San Diego

ADU costs in California vary significantly based on type, size, and whether you're building new or converting existing space:

Garage Conversion

$80,000 - $150,000

Attached ADU

$150,000 - $250,000

Detached ADU

$200,000 - $400,000+

Potential Rental Income

$1,800 - $3,500/month

Average San Diego ADU rental rates (2025)

California ADU Benefits

No Owner Occupancy: Required for new construction
Reduced Fees: Impact fee exemptions for units under 750 sq ft
Fast Permitting: 60-day approval timeline mandated
No Parking Required: Within 1/2 mile of transit
Property Value: Average 20-30% increase in home value
Rental Income: $1,800-$3,500/mo in San Diego
Multi-generational: Perfect for aging parents or adult children

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