ADU Jurisdiction Guide: City of Napa
Fees and Regulations (June 2022)

ADU-allowed Zones

Having ADU on your property is allowed as long as your lot is zoned for residential use (exceptions may vary) and as long as you have an existing single-family home or a multi-family building.

ADU Size Limitations

Floor Area: Maximum of 1,200 Square Feet.

ADU Building Height

The ADU shall be limited to 16’. Building heights greater than 16’, without going over maximum height for the zoning district in which the ADU is located, may be granted with the approval of an administrative permit.

Minimum Lot Size

No minimum. One ADU is allowed per single-family/multi-family lot.

Setbacks Requirements

  • Front: 20 feet
  • Side and Rear: 4feet (Napa Zoning Ordinance)

Parking Space Requirements

  • One (1) parking space per ADU is required to be provided on-site. 
    • Parking spaces may be covered or uncovered, provided as tandem parking on an existing driveway, or on a paved surface in a setback or yard area
  • However, no additional parking is required when at least one of these scenarios applies:
    • The ADU is located within a half-mile of a public transit stop.
    • The ADU is within a designated historic district.
    • The ADU is within a block of car-sharing facilities.
    • The ADU is located where on-street parking permits are required but not offered for ADUs.
  • When a garage or other parking structure or area is demolished in conjunction with the construction of an ADU or converted to an ADU, replacement of the lost parking is not required. However, replacement parking is encouraged and may be located in any configuration on the same lot as the ADU as a covered, uncovered, or tandem parking space.

Owner Occupancy Requirements


Other Regulations

  • A deed restriction is required for a JADU, acknowledging owner occupancy and prohibition on sale separate from primary residence.
  • An ADU shall provide a separate bathroom and a separate kitchen from the primary residence. 
  • An ADU requires a separate exterior entrance.
  • New or separate utility connections may be required, but connection fees or capacity charges shall be proportional to the impact of the ADU on the sewer or water systems.
  • Fire Sprinklers are not required for a new ADU if they are not required in the primary residence. 
  • Bedrooms: Two bedrooms maximum per ADU.
  • No ADU shall be used for transient occupancy.

ADU Permit Fees

  • Maverick 392 (Under 500sqft): $0
  • Maverick 504: $5,114
  • Maverick 748: $7,610
  • Annual Sewer Service Charge: $369.30
  • Plan Check and Inspection Fee: $318

NOTE: Subject to change by July 1st by a construction cost index

Impact Fees

A local agency, special district, or water corporation shall not impose any impact fee upon the development of an accessory dwelling unit less than 750 square feet. Any impact fees charged for an accessory dwelling unit of 750 square feet or more shall be charged proportionately in relation to the square footage of the primary dwelling unit.

Source: AB-68 Land Use: Accessory Dwelling Units


Contact References

City of Napa Planning Division

City of Napa Water Department

City of Napa Sanitation District

  • Address: 1515 Soscol Ferry Road Napa, CA 94558
  • Phone: (707) 258-6000 x401 
  • Email:
  • Website: 
  • Contact Person: Adam Damron
  • Mobile: (707) 258 6007
  • Email:


  • Phone: (707) 257 5918

Fire Prevention

  • Phone: (707) 257 9590

We hope this quick reference guide helps you out in your ADU project. Part of our service if you build with us is the full service of our in-house permit technician who handle the processing of your permit on your behalf with no mark-ups. 

If you’re interested in building with ADU.Works, please don’t hesitate to book a consultation with us or give us a quick call through our number +1 (650) 227 4810. We’ll gladly discuss the specifications of your permit processing and accommodate any questions you may have. Our team looks forward to hearing from you.

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