Accessory Units & Junior Units

Accessory Dwelling Units (ADUs) and Junior Accessory Dwelling Units (JADUs) are an inexpensive way to create smaller, more affordable rental housing units that may provide revenue streams for you, while increasing the availability of rental housing in the county.

Accessory Dwelling Unit Survey

The County of Sonoma and partnering cities want your input on potential barriers and incentives for building accessory dwelling units and/or junior accessory dwelling units. Thank you for taking the time to fill out this survey (English or Spanish) to inform our efforts to increase housing in Sonoma County.

Accessory Dwelling Unit

Accessory dwelling units (ADUs) are backyard cottages up to 1,200 square feet.

An ADU is a small permanent home that may be established in addition to the main dwelling on a parcel zoned for residential use. ADUs may be attached or detached from the main dwelling.

Most residential zoning districts allow one  ADU unless there is a "Z" (Accessory Dwelling Unit Exclusion) overlay zoning on the property..

ADUs can be rented for long-term occupancy, but they cannot be used as vacation rentals.

Read More about Accessory Dwelling Units

Junior Accessory Dwelling Unit

Junior Accessory Dwelling Units (JADUs) are a very small living unit (up to 500 square feet) created out of a bedroom within an existing single family home.

It’s created by adding an efficiency kitchen (see "Efficiency kitchen" Sec. 26-02-140) and exterior door to an existing, legal bedroom. It may include a bathroom or may share a bathroom with the house.

Junior Units are allowed in every zoning district that allows a single-family dwelling.

Can be rented for long-term occupancy, but cannot be used as a vacation rental.

Read More about Junior Dwelling Units

Contact Information

Contact Planning by Phone
Monday – Friday
10:00 AM – 12:00 PM
1:00 PM – 3:00 PM
2550 Ventura Avenue
Santa Rosa, CA 95403
38.465074, -122.723705

State ADU Law

California Department of Housing and Community Development's web site describing state laws and regulations about Accessory Dwelling Units.

View State Web Site

Housing Initiatives

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Permit Sonoma is introducing several initiatives to help meet the County's ambitious housing production goal.

Housing for All Strategy

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multi-unit housing

The County's strategic priority to ensure housing for all income levels.

Find My Property's Zoning

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Zoning Map

Instructions for finding your zoning by address or parcel number.