ADU Cost in Oakland (2026 Guide) | Hamilton Exteriors
Oakland ADU costs range from $150,000 to $375,000 in 2026. Get a detailed breakdown by type, permit fees, and 700+ sq ft pricing. CSLB #1078806.
How Much Does It Cost to Build an ADU in the Bay Area? (2026 Guide)
How much does an ADU cost in the Bay Area? Hamilton Exteriors ADU projects start at $150,000 and can reach $600,000, depending on type, size, and city.
Second Story Addition Cost in the Bay Area
Second story addition cost in San Jose and the Bay Area: $200,000-$400,000 for an 800 sq ft addition with mid-range finishes. Per-city pricing from a licensed architect-GC.