Accessory Dwelling Units

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An “Accessory Dwelling Unit” (or ADU, sometimes called an in-law, secondary, or granny unit) is a second unit on a lot with a primary dwelling unit, which is the main housing unit located on the property. An ADU can be an attached or detached residential dwelling unit. ADUs are frequently rented and cannot be sold separately. ADUs may be built as smaller residences on the same property as a primary single-family residence and are required to provide complete and independent living facilities for one or more persons. ADUs must include a separate entrance, permanent kitchen, sleeping area, living area, and bathroom. ADUs may be built within the existing structure of the primary residence, which could include converting garage space, converting or expanding existing living space, or building out a smaller area of existing living space as a separate unit”. ADUs are also allowed on multifamily parcels and within multifamily buildings. Depending on the situation, ADUs may be as large as 1,000 square feet and could be a studio, one-bedroom, or multi-bedroom unit. An ADU can be an efficiency unit. An ADU may also be a prefabricated or manufactured home.

An attached accessory dwelling unit that is no more than 500 square feet and is contained entirely within a single-family residence is a Junior ADU or a “JADU”. A junior accessory dwelling unit may include separate sanitation facilities or may share sanitation facilities with the existing structure. For the purposes of life/safety regulations and providing utilities such as water, sewer, power, or other utilities, a junior accessory dwelling unit shall not be considered a separate or new dwelling unit.

This website provides home and property owners a summary of the resources to construct, own and operate an ADU in Rohnert Park. Owners may wish to share this website with professionals assisting them in the process, such as architects, designers, contractors, arborists, and engineers.

This website only addresses building ADUs on parcels that already have existing dwelling units – not new construction. If you are interested in constructing a dwelling unit and an ADU, please contact the City to discuss.

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Planning Division

City of Rohnert Park Development Services – Planning Division
130 Avram Ave.
Rohnert Park, CA 94928
Phone: (707) 588-2231
Email: [email protected]

Building Division

City of Rohnert Park Development Services – Building Division
130 Avram Ave.
Rohnert Park, CA 94928
Phone: (707) 588-2240
Email: [email protected]