Secondary Dwelling Units: A Local Housing Solution in Your Own Backyard

What is a Secondary Dwelling Unit?

A Secondary Dwelling Unit (also referred to as an Accessory Dwelling Unit (ADU), second unit, in-law unit, or granny flat) has complete independent living facilities for one or more persons and generally takes one of four forms:

  • Detached: The unit is separated from the primary structure
  • Attached: The unit is attached to the primary structure
  • Repurposed Existing Space: Space (e.g., master bedroom) within the primary residence is converted into an independent living unit
  • Junior Accessory Dwelling Units (JADUs), which are no more than 500 square feet and are typically bedrooms in a single-family home that have an entrance into the unit from the main home and an entrance to the outside from the JADU.

Benefits of Second Dwellings

  • Second dwelling units are an affordable type of home to construct because they do not require paying for land or major new infrastructure.
  • Second dwelling units are installed on existing lots, which helps with contain urban sprawl and preserve open space.
  • Homeowners can construct a second dwelling on their lot or convert an underutilized part of their home such as a garage into a junior accessory dwelling unit. This flexibility benefits not just people renting the space, but the homeowner as well, who can receive an extra monthly rent income.
  • Second dwelling units give homeowners the flexibility to share independent living areas with family members and others, allowing seniors to age in place as they require more care and helping extended families to be near one another while maintaining privacy.

Did you Know?

The Town of Truckee, Nevada County, and Placer County all allow the construction of secondary dwelling units on residential lots as long as they meet building code and zoning requirements. Recent changes in State Law have relaxed the requirements and approval process for second dwelling units, such as reducing parking standards and limiting development fees.