Accessory Dwelling Units

An accessory dwelling unit (ADU)—also known as a granny flat or backyard home—is a secondary residential unit on a property with a proposed or existing home. Recent revisions to California State law have made ADUs easier and more affordable to build.

For questions about how to build an ADU or apply for an ADU permit, please visit the ADU page on the Los Angeles Department of Building and Safety website.

ADU Benefits

Homeowners build ADUs for various reasons, including:

ADUs benefit communities by adding more housing units while maintaining the character of a neighborhood. ADUs are more affordable to build than other types of housing, such as single-family homes, because they do not require buying new land.

ADU Laws and Regulations

Since 2017, California State lawmakers have passed multiple bills to make it easier for homeowners to build ADUs. Five bills made effective on January 1, 2020 have significantly streamlined the ADU construction and approval process. These bills and their key provisions include: 

AB 68 and AB 881: 

SB 13: 

AB 670 and AB 671:

The official ordinance for the City of Los Angeles can be found here
Please visit the ADU page on the Los Angeles Department of Building and Safety website for more information on how to build an ADU and submit your building plans.

Types of ADUs

Homeowners can build many different types of ADUs. ADUs can be attached or detached from the existing home, or located within the existing home. 

ADU images courtesy of Office42 Architecture, Duvivier Architects, and Connect Homes. 

  • Tribune
  • an ADU in Venice
  • ADU in luscious backyard
garage conversion
Garage Conversion

A converted former garage.  

home conversion
Home Conversion

A converted area of the primary home, with its own kitchen and bathroom. 

detached adu
New Detached ADU

A new independent structure, separated from the primary home and often placed in the backyard.

Garage Addition

A new unit that shares at least one wall with the garage. Units can be built above the garage.  


ADU attached to home
Home Addition

A unit that shares at least one wall with the primary home. 


Junior ADU
Junior ADU (JADU)

An ADU of no more than 500 square feet that can be built within a proposed or existing single-family home or accessory structure.