About ADUs

What are ADUs?

An accessory dwelling unit (ADU), also known as a “mother-in-law” or “granny” flat, is an attached or detached residential dwelling unit placed on the same lot that is zoned for single-family, multi-family, or mixed-use/residential. An ADU provides complete independent living facilities for one or more persons. This includes permanent provisions for living, sleeping, eating, cooking, and sanitation, all on the same parcel as the primary, single-family dwelling/multi-family unit lot/or mixed-use/residential property. Each ADU has its own separate entrance, a kitchen, a bathroom and sleeping space.

ADU laws began to be created in 2017 (and have continued to be improved in subsequent years) by the State of California to provide new housing opportunities within existing neighborhoods. The additional units help diversify the market for renters and can provide supplemental income for homeowners. The City must abide by the State’s laws, but they can add items related to public health and safety for all. An ADU increases the value of the property and increases the amount of affordable housing in Laguna Beach.

                                                                         A stand-alone backyard ADU example, less than 800 feet in size.


There are four types of ADUs. All are legal in Laguna Beach, but the size of your yard, setbacks, slopes within your lot, and other conditions may limit the choices you have. All require independent entryways and may be no larger than 16′ in height. Exception: Those over 800 square feet have a height maximum of 12′.

New-build: Detached ADUs/Stand-alone/New square footage creation on a lot: Detached ADUs would not be located in the house or within the existing footprint. They can be located in the back or side yard. The size of a new, free-standing ADU typically ranges from 400-800 square feet, although larger units are possible, including a 2-bedroom ADU at 1,000 square feet. Note that ADUs larger than 800 square feet have much more stringent rules.  Stand-alone ADUs tend to be the most expensive approach and require the largest yard space to conform with the State’s rules regarding setback and building separation requirements. The greatest benefits are that higher rents can be charged and this concept provides more privacy for all parties. One parking space per ADU or bedroom,  would need to be created, but there are exceptions: for example, if the property is located within .5 mile of a public transportation stop, no new parking would be required. Note that in Laguna, the City no longer has a bus system or trolley for the neighborhoods, so the bus stops would be OCTA stops on Coast Highway or Laguna Canyon road.

New-build: Attached ADUs/Addition: An ADU can be created by  by adding more square footage to an existing house or garage; this would be a ground level addition.  An expansion can provide more privacy than an interior conversion. It also may be possible to extend the existing home’s plumbing and electricity rather than creating new utility connections, although the homeowner may want to add a sub-panel for electric service for a 2nd unit if you wish the renter to pay the electric bill for that unit only. They typically require land area, but less than a stand-alone unit. The size of thee units can be 50% of floor area of the existing primary dwelling OR 850 square feet max of 1000 square feet max. for more than one bedroom. The attached ADU that is added cannot exceed 16′ in height, unless it exceeds 800 square feet; then it is 12′ feet max.. There are size limitations for the “addition” and additional parking may need to be created.  There are exceptions, including being located within .5 mile walking distance of a public transit stop or having room in your driveway for tandem parking.

Garage or Carport Conversion: An existing attached or detached garage or carport may be converted into an ADU. It is created within the existing footprint. No new parking is required for these units and they are not limited in size.

Interior Conversion: There are two types of interior conversions. The first type can be walled off in the house and can be any size. It can also be a basement within the 4 walls of the house. It requires a full kitchen including oven. The second type is a Junior ADU, (typically called a JADU).  It is created within the walls of an existing house or attached garage and the size of this unit would be between 150 – 500 square feet and have a kitchenette. An oven is not required. A bathroom in the main house may be shared with the JADU. The conversion would be permanent and have a separate entrance. Note that a deed restriction would need to be recorded/filed with on a junior ADU as the use runs permanently with the land.   No new parking need to be created for the interior JADU or converted interior units.

The State Requires that Laguna Beach Allow ADUs to be Built With Minimal Approval Processes

Typically, in the past, when a Laguna Beach homeowner wanted to build an addition to their house, they had to go through a lengthy entitlement process. This would have included appearing in front of the Design Review Board where neighbors were provided the opportunity to express their support or concerns regarding the project. In the case of ADU and JADU applications, the homeowner does NOT have to appear in front of the City’s Design Review Board. If the application is complete, the State code states that the City must approve the project within 60 days.

                       A creative example of an ADU built inside the existing house (less than 500 square feet; independent entrance).

Some specific key criteria

When you contact Laguna ADU, LLC, we will meet with you at your home in order to help you determine the best location(s) for an ADU. We will provide you with all the criteria required that allows you to create an ADU on your property. Of course, the most expeditious and affordable approach would be to create a unit within the footprint of your existing house or in a garage that already exists.

Some specific criteria outlined by the State of California includes:

  • Height: An ADU cannot be higher than 16′ high. In Laguna, the height of ADUs larger than 800 square feet can only be 12′ high.
  • Size:
    • ADU Detached (new stand-alone unit):
      • 1 bedroom up to 850 square feet max
      • 2+ bedrooms up to 1,000 square feet max
    • ADU Attached & Conversions:  whichever is the lower of the following:
      • 50% of the floor area of the existing primary dwelling
      • a one-bedroom at 850 square feet max
      • two or more bedrooms at 1,000 square feet max
    • Basement conversion: Must already have a “finished” floor and walls — and size is not limited.
    • Interior conversion: no limit in size unless it is a JADU.
    • JADU: Minimum of 150 square feet and maximum of 500 square feet. A JADU is typically inside the existing walls of the house.
  • Setbacks:
    • Front: applicable City zoning/building standards (20′ street setback in front)
    • Side & Rear: A minimum of 4 feet
  • Parking:
    • Regular-stand-alone ADUs or additions : One space per ADU which can be a tandem spot on an existing driveway. There are exceptions, such as if the new ADU will be located within .5 miles of a public transit stop. Note that the City has discontinued the neighborhood bus and trolley service, so those can’t be used to meet the criteria.
    • Conversions: No new parking required if in an existing garage or on a carport
    • JADUs: No new parking requirements.

What are the Benefits of Creating an ADU or Junior ADU on your property?

  1. Increase property value.
  2. Create rental income.
  3. Provide a space for a caretaker.
  4. Create a mother-in-law unit.
  5. Create a unit for a grown child.
  6. Add to the State of California’s (and Laguna’s) rental housing stock.

Click here to see all the updated California Laws for ADUs.