Los Angeles County ADU Guide

City of Los Angeles

ADUs are permitted through a ministerial process in all areas zoned for single-family or multifamily residential use where a dwelling exists or is proposed.

Official source verified 2026-08-16Official jurisdiction resource ↗
01 / Plan path

Choose the right production starting point.

ADUs are permitted through a ministerial process in all areas zoned for single-family or multifamily residential use where a dwelling exists or is proposed.

Express PlanStarting at $4,500

For a qualifying jurisdiction preapproved plan adapted into the property-specific architectural production set.

Custom PlanStarting at $6,500

For an original floor plan and architectural production set developed around the property and homeowner.

02 / Size + fee checkpoints

Size affects more than floor area.

City materials state that an ADU attached to an existing single-family dwelling may not exceed 50 percent of the existing living area, and that attached and detached ADUs may not exceed 1,200 square feet. A setback of no more than four feet from side and rear lot lines is required, and a detached ADU may not be located between the primary dwelling and the street.

Parking requirements may not exceed one space per unit or bedroom. For an ADU over 750 square feet on a lot with a multifamily structure, fees must be proportional to the average size of the dwelling units on the lot. Confirm current fees with Building and Safety.
500 SFConfirm school-fee assessment rules750 SFState impact-fee protection checkpoint1,000 SFTwo-bedroom state minimum allowance1,200 SFCommon local upper-range checkpoint
03 / Site conditions

Property conditions can change the path.

  • Zoning and any specific plan or overlay
  • Hillside ordinance and grading requirements
  • Very High Fire Hazard Severity Zone status
  • Historic Preservation Overlay Zone status
  • Existing dwelling and utility records
04 / Consultant screen

Likely disciplines to evaluate.

  • Structural engineering
  • Title 24 energy documentation
  • Survey where boundaries or topography require it
  • Geotechnical, civil or historic consultation when triggered

Consultants are retained only when required by the property, design, or reviewing agency. Their proposals and coordination are separate from the architectural production fee unless stated otherwise in the agreement.

05 / Property-specific next step

Turn the guide into a preliminary project report.

Enter the address to screen jurisdiction, mapped constraints, likely agencies, drawing requirements, consultants, and the preliminary fee path.

Check the property →Email Bennett Design Studio →
Important: This guide is general planning information, not a zoning determination, permit approval, fee quote, or guarantee of feasibility. Current parcel records, adopted codes, agency interpretations, utility requirements, site investigation, and written agency confirmation control.