Garage Conversion Cost Estimator: Turn Your Garage Into Living Space

Garage Conversion Costs in San Diego

Converting a 2-car garage (400-500 sq ft) in San Diego costs $40,000 to $120,000 depending on scope. A basic conversion (insulation, drywall, flooring, electrical) runs $40,000-$60,000. Adding a bathroom pushes costs to $65,000-$85,000. A full ADU conversion with kitchen, bathroom, and separate entrance reaches $80,000-$120,000. The per-square-foot cost averages $100-$250, significantly less than new construction at $250-$400/sq ft.

What's Involved in a Garage Conversion

Insulation and drywall: $5,000-$10,000. Flooring: $3,000-$8,000 (must address concrete slab moisture). Electrical: $3,000-$8,000 (new circuits, outlets, panel upgrade). HVAC: $3,000-$8,000 (mini-split is most cost-effective). Plumbing: $5,000-$15,000 (if adding bathroom/kitchen). Windows and door: $2,000-$6,000. Permits: $1,000-$3,000. The garage door is typically replaced with a framed wall and window.

Garage Conversion vs. Room Addition

A garage conversion costs 50-70% less than a traditional room addition. You already have a foundation, walls, and roof — you are finishing existing space. Room additions in San Diego cost $300-$500/sq ft for new construction. However, you lose parking and storage. If you have a 2-car garage, consider converting only half and keeping one bay for parking. California law (2024) does not require replacement parking for ADU conversions.

Permits and Regulations

San Diego requires permits for garage conversions. If converting to an ADU, the streamlined process takes 30-60 days. Key requirements: R-13 wall insulation, R-30 ceiling insulation, egress windows in bedrooms, smoke/CO detectors, and separate electrical panel for ADUs. Our cost estimator includes permit fees and code-required upgrades in the total estimate.