Building an Accessory Dwelling Unit (ADU)
Simply, an ADU is a secondary residence with a full kitchen that may be built attached or detached to an existing residence or a remodel of an existing garage into an ADU. These legally rentable ADUs have been also known as Junior ADU, Granny Flat, In-Law Unit, Additional Residential Accommodations ("ARA"), Casita and more.
In 2017 new laws came into effect in the state California allowing and even encouraging the development of ADUs to provide more flexible latitude for home owners to add an ADU.
An ADU may be as large as 1200 SF or more but will vary based on the size of the property and restrictions created by the amount of lot area available or specific city requirements.
Our Staff at BY Building Design is experienced in designing ADUs and can provide complete standard or custom designed ADU plans for you. We provide everything you need for working plans, including the energy code compliance report and the e-submission of your plans to your county or city planning department for review and approval for permits. Feel free to browse the ADU plans below for some ideas on a few standard plans we provide.
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The list of links below will help you learn more about what your city or county requires regarding ADUs. In some cases a city may not provide direct links for ADU information, in which case their municipal code would be the place to look. Please visit your city or county website if a link is not available here. We are adding new information to this list regularly.
New! ADU Funding for Homeowners - Provided By The State of California
New! Senate Bill No. 9 Housing Development - The Planning and Zoning Law provides for the creation of accessory dwelling units by local ordinance. Updated Sept. 16th, 2021
This helpful video is the State Seminar presented to City Building Officials with question and answer session. American Planning Association (APA) webinar for ADU statute updates, effective January 1, 2020
For more information the State website is the best place to start. We recommend you contact your local city or county Planning Department for your particular property.
