How to Build an ADU in Los Angeles From Planning to Completion

Homeowners who plan to build an ADU in Los Angeles benefit from understanding the full design and construction process before starting. A clear roadmap helps prevent delays budget overruns and inspection issues.

The first step to build an ADU in Los Angeles is a feasibility review. This includes evaluating setbacks access utility connections and whether a detached unit or garage conversion ADU is appropriate. Zoning and parcel data should be reviewed using official city and county sources.

Once feasibility is confirmed architectural plans and engineering are prepared. These include structural calculations and energy documentation required for approval. Energy compliance standards are outlined under the California Title Twenty Four Energy Code
https://energycodeace.com

Permit approval is handled by LADBS for City of Los Angeles projects
https://ladbs.org

Unincorporated properties are reviewed by LA County Public Works
https://pw.lacounty.gov

Construction begins after permits are issued and includes foundation framing utilities insulation drywall finishes and inspections. Contractors performing this work must be licensed and in good standing with the California Contractors State License Board
https://www.cslb.ca.gov

Homeowners who build an ADU in Los Angeles with a full service contractor benefit from coordinated inspections and consistent communication. Learn more on our ADU design build process page explore garage conversion ADU services or estimate costs using our ADU cost calculator.