Accessory Dwelling Units (ADU & JADU)

• Number of ADUs/JADUs
  • In general, one ADU and one JADU are permitted on a single family lot.
  • There are some exceptions where the number of total units may be greater, such as proposals with Section 66323 ADUs or ADUs on lots with multifamily residences.
• Size Limits for Attached and Detached ADUs
  • Studio to 1 bedroom ADU
    • 50% of the square footage of the primary residence’s living area, with a cap of 850 sq. ft.
    • Where 50% of the living area does not provide for an 800 square foot ADU, an 800 square feet ADU may be allowed.
  • 2+ bedroom ADU
    • 50% of the square footage of the primary residence’s living area, with a cap of 1,000 sq. ft.
    • Where 50% of the living area does not provide for an 800 square foot ADU, an 800 square feet ADU may be allowed.
• Height Limits
  • Detached ADUs
    • Standard: 16 feet
    • Increased height: Up to 18 feet if located:
      • Within ½ mile of transit
      • On lots with multi-story, multi-family buildings
  • Attached ADUs: Height limit of the zoning district.
• Setbacks
  • Side and rear yards: 4 feet minimum
  • Front yard: Generally, not permitted in front setback. Except, front setback requirements may yield to the extent needed to allow an ADU if the setback would prohibit an 800 square foot ADU with 4-foot side and rear setbacks.
  • Between a detached ADU and main residence: 6 feet, except if this would prohibit an ADU up to 800 square feet with 4 foot side and rear setbacks.
  • No setback required for conversions of existing structures
• Location
  • Detached ADUs must be placed at the rear or side of the primary home, except for ADUs using Government Code Section 66323.
• Parking
  • 1 space per ADU or per bedroom, whichever is less, unless exempt.
    • May be provided as tandem parking to other parking, tandem on a driveway, may be uncovered, and may be located within the front setback.
  • Parking is not required if the ADU is:
    • Within an existing or proposed residence or an existing accessory structure
    • Within ½ mile of public transit
    • Located in a historic district
    • On a lot that needs an on-street parking permit but one is not offered to the ADU.
    • Within on block of a car-share vehicle.
• Exterior Access and Design
  • The ADU needs its own exterior access.
  • For Second Story ADUs: Exterior stairs to a second story attached ADU needs to be located behind the residence.
    • If this is not possible due to site constraints, use one of the following to obscure visibility from the public right-of-way:
      • incorporate screening into the architectural design;
      • addition of trees or landscaping as screening;
      • use of colors on the stairway that match the structure.
  • For Attached ADUs: use exterior colors, materials, and architectural details that match the existing residence.
• Utilities
  • ADUs do not require separate utility connections unless they are part of a new build.
  • Fire sprinklers are not required if the main home does not have them.
  • Units that are more than 150 feet from the curb and where the lot is more than 400 feet from a fire hydrant may require additional review for fire protection.
  • Projects need to have a compliant sewer lateral. A sewer lateral certificate or sewer lateral video needs to be provided to the Pinole Public Works Department for review.

The number of ADUs allowed on multifamily residential lots are described below:

• ADUs within Existing Space: Non-habitable spaces (e.g., storage rooms, attics, basements) can be converted to ADUs, not to exceed 25% of the existing multifamily units.
• Detached ADUs
  • Up to 2 detached ADUs can be constructed on a lot with proposed multifamily dwellings.
  • Up to 8 detached ADUs can be constructed on a lot with existing multifamily dwellings, provided the total number of ADUs does not exceed the existing units on the lot.

Government Code Section 66323 provides a process for creating certain types of ADUs/JADUs that meet specific criteria. These units are not required to meet all of the typical objective development or design standards otherwise required under the Zoning Code but must meet the listed criteria.*

For more information, please click on the link for Government Code Section 66323 or see the ADU/JADU Checklist available on the Planning Permit Information webpage.

*Please note: Units must still comply with building code and engineering standards. Permits, occupancy, impact fees for ADUs 750 square feet or greater, and other requirements not related to development standards still apply.

• ADUs that are 750 square feet or larger are required to pay an additional City development impact fee. The development impact fee is based on ADU size divided by the residence size multiplied by the Development Impact Fee (based on ADU bedroom count) shown in the Master Fee Schedule.
• ADUs that are less than 750 square feet are not required to pay City development impact fees.
• ADUs may still be required to pay fees established by outside districts/agencies, such as West Contra Costa Unified School District and the West Contra Costa Transportation Committee. More information on outside fees can be found on the City’s Fees webpage.