What is difference between Adu and Jadu?

Accessory Dwelling Units (ADUs) have been known by many names: granny flats, in-law units, backyard cottages, secondary units and more. No matter what you call them, ADUs are an innovative, affordable, effective option for adding much needed housing in California. HCD is the state’s leader on local ADU ordinances, which while optional have grown exponentially in number as more cities, counties, and homeowners become interested in ADUs as one solution to increasing the supply of affordable housing.

According to California’s legislation, a JADU is officially designated as a separate dwelling unit of up to 500 square feet. It must have a separate entrance, distinct from the main home. An ADU, in comparison, can be up to 1500 square feet in some locales.


ADUs, or accessory dwelling units, have been an ad-hoc housing option forever. They are also known as granny flats, laneway homes, and carriage houses. Accessory dwelling units typically solve one or two challenges for homeowners: money and family.

An ADU can help a family member, such as a senior parent or a young adult, with a decent place to live. The structure is not subject to the normal rental market of a senior-care facility or living with multiple roommates.

Additionally, the budgetary bump from rental income could make living in certain properties affordable. An ADU can also be an asset at the time of resale if the unit is code-approved and permitted. Now, the JADU, or junior accessory dwelling unit, can be a consideration.

Junior accessory dwelling units as affordable housing

In recent years, they’ve become more recognized and acknowledged as a benefit in places with expensive housing. They’re now built using formalized processes for their construction. In the past, it would have been a garage makeover, for example. In another trend toward affordable housing options, California has recognized the JADU.

A JADU must be located within the walls of a proposed or existing space.

You cannot put up a small shed and call it a JADU. In fact, you cannot build any new space for the JADU. The JADU can be located within a converted garage, but that will trigger a parking requirement, meaning you will have to replace any converted parking spaces on a 1:1 basis. Just adding a JADU to your existing home, however, does not trigger a parking requirement, so that’s good news.

Beyond that, the details can change in each municipality. If you’re interested in a JADU project, you’ll need to think hyper-local to ensure that you meet the requirements for permitting. Yes, that means you’ll need to meet the state code at a minimum, and then comply with the local ordinances that apply. You’ll go through a specific permitting process for this project, so an experienced professional would be an invaluable resource.

For more information call us today for a free estimate Tel. (310)-984-9398 or Contact us: TheAduGuys@gmail.com and you’ll learn everything you need to know about the ADU process – from planning & permitting to designing & construction.

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