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Released by: Permit Sonoma
For Immediate Release

New and Modified Zoning Regulations for Housing

Accessory Units and Junior Units

Santa Rosa, CA  –  March 7, 2017  –  On January 24, 2017, the Board of Supervisors adopted code changes for accessory dwelling units (“accessory units”) and junior accessory dwelling units (“junior units”).  This action was in response to changes in State law and the housing crisis. 

These new rules for accessory units, formerly called second units, make it easier for property owners to build those units.  Relaxed regulations include smaller lot sizes, some reduced setbacks, and a simpler, faster permit process. 

These changes also allow a new type of housing called a junior unit.  A junior unit is a very small living unit, up to 500 square feet, created within an existing bedroom in a house.  Junior units are allowed in all zoning districts where single-family dwellings are allowed.  Property owners may construct a junior unit with a building permit; a separate planning permit is not required.

Board of Supervisors Chair Shirlee Zane commented, “I am confident that these new accessory unit zoning regulations will lead to construction of more affordable housing, sooner rather than later.  Adding a junior unit or accessory unit to eligible properties is an efficient way to generate income for the property owner while helping to address Sonoma County’s housing crisis.”

Both accessory units and junior units may be rented; neither unit can be used for short-term rentals (e.g., vacation rentals).  These new rules apply to properties located in unincorporated areas of the county, excluding the coastal zone.

Information may be found at the project website: or by contacting County staff at or (707) 565-7388.


Contact Information

Bradley Dunn
Policy Manager
County of Sonoma
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