Garage Conversion ADU Guide for the Bay Area: Cost, Rules, and Process (2026)
Hamilton Exteriors ADU projects start at $150,000 and can reach $600,000. See where a garage conversion sits, the California parking and setback rules, and the build process.
Second Story Addition Cost Walnut Creek | Hamilton Exteriors
Second story addition cost in Walnut Creek, CA ranges from $200 to $400 per square foot. Architect-led pricing, permit fees, and 2026 cost factors.
ADU Construction Cost Walnut Creek | 2026 | Hamilton Exteriors
Walnut Creek ADU costs range from $170,000 to $370,000 for a detached unit in 2026. Garage conversions start around $150,000. Architect-led design-build.
Second Story Addition Cost in San Ramon | Hamilton Exteriors
San Ramon second story addition costs range from $200 to $400 per square foot in 2026. Get a detailed breakdown of pricing, permits, and fire zone
ADU Construction Cost San Ramon (2026 Guide) | Hamilton Exteriors
How much does ADU construction cost in San Ramon? Detached units run $200K–$375K, garage conversions $150K–$200K. Architect-led design-build. CSLB #1078806.
Second Story Addition Cost in Sunnyvale | Hamilton Exteriors
Sunnyvale second story addition costs range from $200-$500 per sq ft in 2026. Architect-led pricing, permit guidance, and city-specific factors. CSLB #1078806.
ADU Construction Cost in Sunnyvale | Hamilton Exteriors
ADU construction in Sunnyvale costs $200,000 to $450,000 in 2026. Detailed cost breakdown by type, permit fees, and ROI. CSLB #1078806. Free on-site estimate.
Second Story Addition Cost in Saratoga CA | Hamilton Exteriors
Second story addition costs in Saratoga, CA range from $350 to $650 per square foot. 2026 pricing guide with permit fees, fire zone rules, and seismic
ADU Cost in Saratoga CA 2026 | Hamilton Exteriors
Saratoga ADU costs range from $150,000 to $400,000 in 2026. Architect-led guide with permit fees, WUI fire zone costs, and real pricing. CSLB #1078806.
Santa Clara Home Addition Cost 2026 | Hamilton Exteriors
Santa Clara home additions cost $200 to $450 per square foot in 2026. Architect-led guide to second story, room extension, and ADU pricing. CSLB #1078806.
ADU Cost in Santa Clara (2026 Guide) | Hamilton Exteriors
ADU construction in Santa Clara costs $200,000 to $400,000 for a detached unit. Get real 2026 pricing, permit fees, and ROI data. CSLB #1078806.
Second Story Addition Cost San Jose | Hamilton Exteriors
Second story addition costs in San Jose range from $250,000 to $600,000. Get a detailed breakdown of pricing, permits, and planning. CSLB #1078806.
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