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ADU Construction · Los Angeles & Orange County

Garage Conversion ADU in Los Angeles & Orange County

Convert your existing garage into a permitted, livable ADU — often the fastest and most cost-effective way to add an income unit, home office, or guest space. Serving Los Angeles County and Orange County, permits-to-turnkey.

  • Plans & permitting support
  • Clear written estimates
  • Licensed GC · License #1124836
Call (323) 479-1859

Free ADU Feasibility Call

Serving LA & OC. We review every request and contact you with next steps.

By submitting, you agree that we may contact you about your project. See our privacy policy. We serve Los Angeles and Orange counties on these ADU pages.

ADU Types

Garage conversions and other ADU options.

Whether you're converting a garage or building new, we help you choose the right ADU path for your property.

Garage Conversion ADU

Convert an existing garage into a permitted, livable unit — often the fastest and most cost-effective ADU path.

Detached ADU

A new, free-standing structure on your property — typically the most flexible in design and layout.

Attached ADU

A new unit added to your existing home, sharing one or more walls with the primary residence.

JADU

A Junior ADU built within the existing footprint of your home, up to 500 sq ft.

Our Process

A clear, organized ADU process — from idea to keys.

We coordinate planning, permits, and construction so you have one team and one written contract.

  1. 1

    Free feasibility call

    We discuss your goals, lot, and zoning to confirm what's possible.

  2. 2

    Plans & design

    Coordination with licensed design professionals to develop plans for your property.

  3. 3

    Permitting

    Plan check submittals, corrections, and city coordination.

  4. 4

    Construction

    Site prep, foundation, framing, MEP, finishes — managed under one contract.

  5. 5

    Final inspection & turnover

    Inspections, sign-off, and a clean turnover of your finished ADU.

Costs

ADU cost ranges.

Every project is different — these ranges are typical for projects in Southern California. We provide a clear written estimate after a feasibility call.

  • Standard 1-car garage conversion$90k–$140k
  • 2-car garage conversion$120k–$180k
  • Garage conversion + small addition$160k–$220k

Ranges exclude permit fees, utility upgrades, and site-specific conditions.

Timeline

Typical ADU timeline.

From plans through final inspection. Actual schedules depend on city, scope, and site conditions.

  • Feasibility & design2–6 weeks
  • Permitting & plan check2–6 months
  • Construction4–8 months
  • Inspections & turnover2–4 weeks

Permitting Help

We handle the permit process across LA & OC.

ADU rules differ by jurisdiction. We coordinate plan check submittals, corrections, and inspections so you don't have to navigate it alone.

  • Zoning and feasibility review
  • Plan check submittals
  • Corrections & resubmittals
  • Inspection coordination
  • Utility and setback guidance

Why Build Construction Corporation

  • Licensed General Contractor (License #1124836)
  • Permits-to-turnkey ADU delivery
  • Serving Los Angeles & Orange County and LA County
  • Clear written estimates and contracts
  • Organized project communication

FAQ

ADU questions in Los Angeles & Orange County.

Common questions homeowners ask before starting an ADU project.

Get Started

Ready to explore an ADU in LA & OC?

Tell us about the property and what you have in mind. We'll review the scope and follow up with next steps. If you are still exploring, the property planner is an optional starting point.

Free ADU Feasibility Call

Tell us about your property and we'll contact you with next steps.

By submitting, you agree that we may contact you about your project. See our privacy policy. We serve Los Angeles and Orange counties on these ADU pages.

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Planning a project?

Send us your project details and we'll respond with next steps and a clear written estimate.