The simplest definition of an accessory dwelling unit (ADU) – also known as a ‘granny flat,’ ‘in-law apartment’ or ‘backyard cottage’ – is a secondary independent structure built on the same land as an existing primary single-family house. An ADU may be built as detached units in the backyard, over a garage (where allowed), or as a garage conversion (detached or attached). An existing room within a house may also be converted into a separate unit (this is considered a Jr. ADU) as long as it meets state and/or local regulations.
These secondary units, made for one or two persons, range in size of about 150-800 square feet depending on the jurisdiction and the size of the lot and primary house. Units must provide living, sleeping, eating, cooking and sanitation through a partial or full kitchen, shared or separate baths, depending if it’s an ADU or a Jr. ADU and on the state and/or local jurisdiction’s requirements. ADUs can be used by homeowners to house their adult children or aging parents – or use as a rental unit as a source of additional income.
Several bills passed by the California Legislature that took effect January 2017 – and bills clarifying the law in January 2018 – make it easier for homeowners to build secondary units by relaxing development standards (such as setbacks, parking, height requirements, etc.) and lowering cost of impact fees (e.g. utility fees). Local jurisdictions may choose to relax development standards even further.
ADUs can play a role to alleviate the housing crisis in the greater Bay Area and are considered to be a highly sustainable option as the small footprint can reduce greenhouse gas emissions, reuse existing infrastructure and foster more dense land use.
Housing Trust is pleased to have the opportunity to address issues with the development of ADUs by offering technical and financial assistance as we work to bring more affordable housing to our communities – and we thank JP Morgan Chase and their PRO Neighborhoods initiative for their financial support.
Housing Trust is currently developing a program that will include a series of workshops to assist homeowners navigate the design, local permitting process, contracting, financing and construction process as well as education on becoming a landlord. We are also crafting the type and amount of financial support we could offer a homeowner to incentivize the construction of ADUs. We plan to launch this program sometime in the spring of 2018 and will communicate via this page as well as our mailing list, so please be sure to submit your contact information through our ADU interest list form below.