The City of Dublin permits ADUs across most residential zones. Dublin follows both state and local ADU laws, allowing most single-family homes to build one detached ADU and one Junior ADU (JADU) per lot. Multi-family properties may be eligible for multiple ADUs, depending on site conditions.

Dublin aligns with California’s broader ADU legislation but has its own requirements for height, setbacks, and design review.

• Detached ADU: A standalone unit located on the same lot as the primary residence.
• Attached ADU: A unit physically connected to the main home, sharing a wall but with a separate entrance.
• Conversion ADU: Created by converting an existing structure, such as a garage, basement, or attic, into a livable unit. 
• Junior ADU (JADU): A smaller unit, up to 500 sq ft, built entirely within an existing single-family home, including an attached garage

• Maximum Size:
  
  • Detached: Up to 1,200 sq ft
  • Attached: Up to 50% of the primary dwelling's net floor area, up to 1,200 sq ft. 
• Setbacks:
  
  • Minimum 4–5 ft from side and rear property lines, depending on ADU type and lot configuration
• Height Limits:
  
  • Typically,16 ft, up to 24 ft, depending on location, zone, and unit type
• Parking Requirements:
  
  • Additional parking is not required if the ADU is:
    
    • Located within ½ mile of public transit
    • Converted from an existing structure (e.g., garage, basement, or other accessory building)
    • Located in a historic district or other designated area with special standards

To build an ADU in Dublin, the following approvals are typically required:

• Zoning compliance review
• Site plan and elevations
• Architectural drawings
• Structural calculations and engineering
• Title 24 energy documentation
• Permit submission through the City of Dublin’s Citizen Self-Service (CSS) Portal
  

Homeowners should also review Dublin’s current fee schedule, utility connection requirements, and fire code compliance.

Permit review times in Dublin typically range from 6 to 12 weeks, depending on project complexity and City workload. Projects requiring corrections or plan revisions may take longer. Engaging professionals familiar with Dublin’s ADU process can help streamline approval and reduce delays.

Most residential zones in Dublin are eligible for ADUs, including single-family residential (R-1) and other designated residential zones. A primary dwelling must exist or be proposed on the lot. There are generally no minimum lot size requirements for ADUs in most areas, although some hillside, environmentally sensitive, or special overlay zones may have additional restrictions regarding setbacks, height, or design.

For the most current and complete information, refer directly to the City of Dublin.