The City of El Cerrito permits ADUs across most residential zones. El Cerrito 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.

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

• Detached ADU: A standalone unit separate from the primary dwelling.
• Attached ADU: A unit physically connected to the primary dwelling.
• Conversion ADU: A unit created by converting existing non-livable space within the primary dwelling or accessory structures (e.g., garages, basements). 
• Junior ADU (JADU): A unit no larger than 500 sq ft, entirely within the existing primary dwelling.

• Maximum Size:
  
  • Detached: Up to 850 sq ft.
  • Attached: Up to 50% of the primary dwelling’s floor area, not exceeding 1,000 sq ft.
• Setbacks:
  
  • Minimum 4 ft from side and rear property lines
• Height Limits:
  
  • Typically, 18 ft, up to 25–35 ft depending on daylight plane compliance.
• Parking Requirements:
  
  • Additional parking is not required if the ADU is:
    
    • Located within half a mile of public transit
    • Converted from an existing structure
    • In a historic district or environmentally sensitive area

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

• Zoning Compliance Review: Verify that the intended ADU meets zoning standards.
• Site Plan and Elevations: Include detailed drawings of the ADU's layout and location. 
• Architectural Drawings: Introduce overall plans detailing the ADU's layout and construction.
• Structural Calculations and Engineering: Add calculations and engineering information to guarantee the structural integrity of the ADU.
• Title 24 Energy Documentation: Assure compliance with California's energy standards.
• Permit Submission: Present applications via the City of El Cerrito's online portal.
  

Homeowners also need to go through El Cerrito's existing fee schedule, utility connection requirements, and fire code requirements.

The duration of permit review and approval of Accessory Dwelling Units (ADUs) in El Cerrito varies with the project complexity and the city's workload. No timeframes are given on the official city website, but employing experts familiar with working in El Cerrito's ADU process helps to quicken the approval process.

All single-family, duplex, and multi-family residential areas in El Cerrito qualify for ADUs. There are no minimum lot sizes for most ADU areas. There may be special conditions in the hillside or environmentally sensitive areas for setbacks, height, or lot coverage.

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