Accessory Structures in Santa Rosa, CA (2026)
4 verified accessory structures rules for Santa Rosa, California, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
Santa Rosa allows one ADU plus one JADU on single-family lots under Zoning Code Section 20-42.130, adopted by urgency Ordinance on March 3, 2020 to align with California Government Code Sections 65852.2 and 65852.22. Detached ADUs are capped at 1,200 sq ft with 4-ft side/rear setbacks and a 16-ft (one-story) or 27-ft (two-story) height limit; JADUs are capped at 500 sq ft and must sit entirely within the existing single-family dwelling walls.
Santa Rosa ADU & JADU Ordinance (Sec. 20-42.130)
Some RestrictionsSanta Rosa City Code, Title 20 (Zoning), Section 20-42.130 (Accessory dwelling units), adopted by urgency Ordinance, March 3, 2020 (File REZ20-001)
20-42.130 Accessory dwelling units. Accessory dwelling units shall comply with the requirements of this Section, where allowed by Division 2 (Zoning Districts and Allowable Land Uses). A. Purpose. The provisions of this Section are intended to set standards, in compliance with California Government Code Sections 65852.2, and 65852.22, for the development of accessory dwelling units so as to inc...
Shed Rules
Santa Rosa requires a building permit for any accessory structure over 120 square feet of floor area, per the city's Accessory Structure Requirements Policy (Policy No. 2.5.3, effective June 2, 2005, revised July 2011) which implements California Building Code Section 1808 and Santa Rosa Zoning Code Section 20-42.030. Sheds 120 sq ft or smaller are exempt from a structural permit but cannot be used as habitable or conditioned space, and any electrical or plumbing installation requires a separate permit.
Shed & Accessory Structure Permit Rules (CBC 1808 / 20-42.030)
Some RestrictionsSanta Rosa Community Development - Building and Code Compliance, Accessory Structure Requirements, Policy No. 2.5.3, Effective June 2, 2005, Revised July 2011 (implementing CBC 1808 and Santa Rosa City Code Sec. 20-42.030)
PURPOSE: The following policy clarifies the requirement for foundations under accessory structures. Previous code (2001 CBC) allowed a one story wood or metal frame building not used for human occupancy and not over 400 square feet in floor area may be constructed with walls supported on a wood foundation plate when approved by the building official. This exception was removed from the CBC in 2...
Garage Conversions
Santa Rosa permits garage-to-ADU conversions ministerially under Zoning Code Section 20-42.130 with no replacement parking required and no setback required for existing legally constructed garages converted to an ADU with independent exterior access. Conversion to non-habitable storage requires a standard building permit, while conversion to habitable space (ADU or JADU) follows the city's 2020 ADU ordinance and California Government Code Sections 65852.2 and 65852.22.
Garage-to-ADU Conversions (Sec. 20-42.130 E.2.c / E.10.h)
Few RestrictionsSanta Rosa City Code, Title 20 (Zoning), Section 20-42.130(E)(2)(c), (E)(4)(b), and (E)(10)(h), adopted by urgency Ordinance, March 3, 2020 (File REZ20-001)
c. No setback shall be required for an existing legally constructed living area, garage, or other accessory structure that is converted to an accessory dwelling unit with independent exterior access from an existing or proposed residence. A setback of five feet from the side and rear property lines is required for an accessory dwelling unit constructed above an existing legally constructed gara...
Carport Rules
Santa Rosa Zoning Code Section 20-42.030 caps carports at 16 feet tall and requires the carport face to sit at least 19 feet back from the property line, curb, or sidewalk on street-facing lots. Any structure over 120 sq ft needs a building permit. Carports are subject to Design Review and the 2022 California Building Code.
accessory-structures/carport-rules
Some RestrictionsLooking for Sonoma County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Santa Rosa city rules.
Accessory Structures in Sonoma County →