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ADUs & Additions

63 articles about adus & additions

Written by licensed contractors · CSLB #1078806 · 500+ projects completed
ADU Construction Cost in Antioch, CA | Hamilton Exteriors
Cost GuideAdu

ADU Construction Cost in Antioch, CA | Hamilton Exteriors

ADU construction in Antioch costs $150,000 to $350,000 for a detached unit. Garage conversions start around $150,000. Get a free on-site estimate.

Home Addition Cost in San Leandro | Hamilton Exteriors
Cost GuideAdditions

Home Addition Cost in San Leandro | Hamilton Exteriors

Home addition cost in San Leandro ranges from $175 to $400 per square foot. Architect-led design-build with itemized pricing. CSLB #1078806.

ADU Cost in San Leandro, CA (2026 Guide) | Hamilton Exteriors
Cost GuideAdu

ADU Cost in San Leandro, CA (2026 Guide) | Hamilton Exteriors

How much does an ADU cost in San Leandro? Real 2026 pricing for detached, garage conversion, and JADU projects. Permit fees, timelines, and ROI. CSLB #1078806.

Second Story Addition Cost Hayward 2026 | Hamilton Exteriors
Cost GuideAdditions

Second Story Addition Cost Hayward 2026 | Hamilton Exteriors

Second story addition costs in Hayward range from $200 to $400 per square foot in 2026. Get a detailed breakdown of pricing, permits, and timelines.

ADU Construction Cost Hayward | 2026 | Hamilton Exteriors
Cost GuideAdu

ADU Construction Cost Hayward | 2026 | Hamilton Exteriors

ADU construction in Hayward costs $160,000 to $300,000 for a detached unit. Garage conversions start at $150,000. Get a free on-site estimate. CSLB #1078806.

Second Story Addition Cost in Fremont CA | Hamilton Exteriors
Cost GuideAdditions

Second Story Addition Cost in Fremont CA | Hamilton Exteriors

Fremont second story addition costs range from $200 to $400 per square foot in 2026. Architect-led pricing, permit guidance, and seismic requirements.

ADU Cost in Fremont CA (2026 Guide) | Hamilton Exteriors
Cost GuideAdu

ADU Cost in Fremont CA (2026 Guide) | Hamilton Exteriors

Fremont ADU construction costs range from $170,000 to $310,000 for a detached unit in 2026. Garage conversions start lower. Architect-led design-build.

Second Story Addition Cost in Castro Valley | Hamilton Exteriors
Cost GuideAdditions

Second Story Addition Cost in Castro Valley | Hamilton Exteriors

Second story addition costs in Castro Valley range from $200 to $400 per square foot. Get a detailed breakdown of pricing, permits, and seismic requirements

ADU Construction Cost in Castro Valley | Hamilton Exteriors
Cost GuideAdu

ADU Construction Cost in Castro Valley | Hamilton Exteriors

ADU construction in Castro Valley costs $160,000 to $375,000. Architect-led pricing guide with permit fees, timelines, and site factors. CSLB #1078806.

Second Story Addition Cost in Berkeley CA | Hamilton Exteriors
Cost GuideAdditions

Second Story Addition Cost in Berkeley CA | Hamilton Exteriors

Second story addition costs in Berkeley CA range from $200 to $500 per square foot. Architect-led design-build with itemized pricing. CSLB #1078806.

ADU Construction Cost in Berkeley | Hamilton Exteriors
Cost GuideAdu

ADU Construction Cost in Berkeley | Hamilton Exteriors

ADU construction in Berkeley costs $220,000 to $400,000 for a detached unit. Get a detailed cost breakdown, permit fees, and local regulations. CSLB #1078806.

Second Story Addition Cost in Oakland 2026 | Hamilton Exteriors
Cost GuideAdditions

Second Story Addition Cost in Oakland 2026 | Hamilton Exteriors

Oakland second story addition costs range from $200 to $400 per sq ft in 2026. Architect-led pricing, permit16 weeks. CSLB #1078806. Free on-site estimate.

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