Accessory Structures in Napa, CA (2026)
5 verified accessory structures rules for Napa, California, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
City of Napa permits ADUs and JADUs on residential lots under Napa Municipal Code Title 17, consistent with California Gov Code §65852.2 (renumbered §66310-66339 by SB 477) and §65852.22. Detached ADUs up to 1,200 sq ft; JADUs to 500 sq ft.
ADU Rules in Napa, CA
Few RestrictionsADU Permits
City of Napa must approve or deny ADU permit applications ministerially within 60 days under California Gov Code §65852.2(b). Applications go through the Building Division with site plan, floor plan, elevations, and Title 24 documentation. No discretionary hearing for code-compliant ADUs.
ADU Permit Process in Napa, CA
Some RestrictionsADU Impact Fees
ADUs under 750 sq ft are exempt from all city development impact fees under California Gov Code §65852.2(f)(3). ADUs 750 sq ft and larger pay impact fees proportional to the primary dwelling. Napa cannot require new utility connections for ADUs sharing existing service.
ADU Impact Fees in Napa, CA
Few RestrictionsShed Rules
City of Napa follows California Building Code §105.2 and Napa Municipal Code Title 17. Detached one-story sheds under 120 sq ft are exempt from a building permit but must meet zoning setbacks, height limits, and lot-coverage. Larger sheds need a permit.
Shed Rules in Napa, CA
Few RestrictionsGarage Conversions
Garage-to-ADU conversions in Napa are ministerial by right under California Gov Code §65852.2 and Napa Municipal Code Title 17. Existing-footprint conversions need no added setback, and the city cannot require replacement parking. Title 24 / CalGreen energy compliance applies.
Garage Conversion Rules in Napa, CA
Few RestrictionsLooking for Napa County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Napa city rules.
Accessory Structures in Napa County →