Bay Area ADU builders

Why Homeowners Choose Metricon as Their Bay Area ADU Contractor

Finding a reliable ADU builder in the Bay Area means looking for a team that balances architectural design with local permitting expertise. Unlike traditional wood-frame builders, our team uses advanced, cold-formed steel panelized prefab systems. This engineering delivers faster build times, zero termite risk, and superior fire resistance, giving you the personalized service of a local custom ADU contractor paired with modern manufacturing precision.

Start by reviewing Bay Area city ADU guidelines, then compare prefab and custom ADU plans or browse completed project work.

  1. 01

    Feasibility

    Review your lot, local rules, access, utilities, and ADU goals before committing to a scope.

  2. 02

    Design + permits

    Coordinate architectural plans, engineering, and city submittals in one accountable workflow.

  3. 03

    Build

    Move from approved plans to a durable steel-frame ADU with one construction team.

One Bay Area team, from planning to construction

  • Property-specific feasibility, zoning review, and permitting strategy before you commit to a detached ADU scope.
  • Architectural design, structural coordination, prefab steel-frame detailing, and construction planning in one builder-led workflow.
  • Turnkey execution covering foundation, utilities, inspections, and final build delivery for Bay Area homeowners.

Prefab Steel-Frame ADUs vs. Custom Stick-Built

Looking for a prefab home extension or detached backyard ADU? Our cold-formed steel panelized prefab systems offer faster build times, zero termite risk, and superior fire resistance compared to traditional wood framing.

Explore ADU plans

Bay Area City ADU Permitting & Zoning Guidelines

Every Bay Area jurisdiction applies its own ADU standards around setbacks, maximum size, utility tie-ins, parking, and design review. Use the city directory below to compare local rules and start with the planning path that fits your lot.

Browse Bay Area city guidelines

Featured Prefab & Custom ADU Models & Pricing

Browse our featured floor plans to compare studio, one-bedroom, two-bedroom, and larger detached ADU layouts, then narrow down which prefab-friendly or custom model direction best matches your backyard and budget.

View completed ADU projects

Licensed Bay Area General Contractor (CSLB #1128717)

Metricon Homes is headquartered in San Ramon, California and serves homeowners across the Bay Area with contractor-led delivery, architectural coordination, permit support, and prefab steel-frame construction expertise tailored to California ADU projects.

San Mateo ADU builders

Planning an ADU in San Mateo County? Review local design-build considerations, detached ADU options, and permitting next steps.

Explore San Mateo ADUs

Compare Bay Area ADU plans

See ADU sizes, layouts, bedroom counts, and prefab-friendly plan options before requesting a feasibility review.

Browse ADU plans

View finished project work

Look through Metricon Homes project photos for design quality, construction details, and homeowner inspiration.

Open project gallery

City ADU planning guide

Find your city's Bay Area ADU rules

ADU rules are set city by city, not region-wide. California allows detached ADUs up to 1,200 sq. ft. under the statewide framework, but each Bay Area jurisdiction can set its own local maximum, setbacks, parking and permitting steps. Choose your city below for the specific rules that apply to your property.

San Francisco County

San Francisco

Alameda County

AlamedaAlbanyBerkeleyCastro ValleyDublinEmeryvilleFremontHaywardLivermoreNewarkOaklandPleasantonSan LeandroSan Lorenzo

Contra Costa County

AntiochBlackhawkBrentwoodClaytonConcordCrockettDanvilleEl CerritoEl SobranteHerculesLafayetteMartinezMoragaOakleyOrindaPinolePittsburgRichmond

San Mateo County

BelmontBurlingameEast Palo AltoFoster CityHillsboroughMenlo ParkMillbraePacificaPortola ValleyRedwood CitySan BrunoSan CarlosSan Mateo

Santa Clara County

CampbellCupertinoGilroyLos AltosLos Altos HillsLos GatosMilpitasMonte SerenoMorgan HillMountain ViewPalo AltoSan JoseSanta ClaraSunnyvale

Marin County

BelvedereCorte MaderaFairfaxGreenbraeMill ValleyNovatoSan Anselmo

Solano County

BeniciaVallejo

Don't see your city listed, or building somewhere else in California? Contact Metricon Homes and we can confirm the rules for any property.

ADU planning resources

Explore Bay Area ADU service areas and planning next steps

Compare nearby ADU city pages, review plan options, and move from early research to a property-specific ADU conversation.

Start here

Compare detached ADU plans

Review sizes, layouts, and configurable ADU options before your feasibility call.

Browse ADU plans
Budget

Understand ADU financing

See common funding paths and how homeowners think about ADU return potential.

Explore ADU financing
Process

Know what happens next

Walk through feasibility, design, permitting, and construction with Metricon Homes.

See how ADUs work

Nearby Bay Area ADU pages

Alameda ADUsBerkeley ADUsCampbell ADUsConcord ADUsCupertino ADUsDanville ADUsDublin ADUsFremont ADUsHayward ADUsLivermore ADUsLos Altos ADUs

Build Your ADU with Metricon Homes

Metricon Homes helps you plan and build a fully custom Accessory Dwelling Unit tailored to your property, lot, and local regulations. From feasibility and design through permitting and construction, our team manages the entire process so you can add flexible living space, host family, or generate rental income with confidence.

Contact us today for a free property assessment and start planning your ADU.

CALL (833) 400-2497

Explore our ADU plans

Contact Us(833) 400-2497