ADU Cost San Diego (2026)

Real 2026 pricing for detached ADUs, garage conversions, and additions in San Diego County. Get a written estimate for your address.

2026 ADU Cost Ranges in San Diego

ADU costs in San Diego depend on the type of ADU, square footage, finish level, and site conditions. Here are typical 2026 price ranges:

$80K–$200K

$250K–$500K+

$200K–$400K

Square footage and layout. 1-bedroom vs. 2-bedroom adds $40K–$80K.
Finish level. Standard vs. designer finishes can swing $50K+.
Site conditions. Slope, soil, and access affect foundation and grading costs.
Utility runs. Distance from main panel and sewer line connections.
Permit and impact fees. Typically $10K–$30K depending on jurisdiction.
Title 24 compliance. Insulation, HVAC, solar, and energy upgrades.

What's the cheapest type of ADU in San Diego?

Garage conversions are typically the lowest-cost option, starting around $80K, because you're reusing the existing structure.

Are ADU costs going up in 2026?

Material costs have stabilized in 2026, but labor and permit fees continue to rise modestly. Building sooner generally saves money.

Can I finance an ADU in San Diego?

Yes. HELOCs, cash-out refis, and ADU-specific loan products are all common. Some lenders count projected rental income toward qualifying.

How much does an ADU add to property value?

Permitted ADUs typically add $150K–$400K+ to your San Diego home's appraised value.