What’s a JADU (and can I build one)?

What's the difference between an ADU and a JADU? Why build a JADU? Is my home eligible? Learn the answers to these questions (and many more) in this blog post.

Last updated 
January 3, 2023
What’s a JADU (and can I build one)?

What’s a JADU (and can I build one)?

Recent California laws AB 68 and AB 881 allow California homeowners to build one ADU and one JADU on their property, but what’s the difference between the two?

In this blog post, we’ll explain what a JADU is, answer some common questions, and help you decide if a JADU is the right choice for you and your home.

What is a JADU?

Most people know that an ADU is an Accessory Dwelling Unit, but what about a JADU? A JADU is a Junior Accessory Dwelling Unit. In addition to being smaller than the typical accessory dwelling unit (as the name suggests), there are a number of distinctions between the two.


First, a junior accessory dwelling unit must be located within a proposed or existing single-family home or attached accessory structure (like a garage).

Spaces that can be converted into a JADU include:

  • Attached garages
  • Attics
  • Basements
  • Primary bedrooms
  • Rec rooms


The JADU requires a separate exterior entrance. No interior entry to the main house is required.


JADUs can be no larger than 500 square feet in floor area. However, some jurisdictions allow an additional 150 square feet for ingress/egress (state law requires that cities allow this for ADUs, but it’s up to the jurisdiction to decide with JADUs).

Bathroom & Kitchen

A JADU’s bathroom can be separate from or shared with the primary unit, but it must have its own separate kitchen. So-called “efficiency kitchens” are allowed, which have a 12" wide 2 burner electric cooktop, a 24" wide undercounter fridge, and a compact sink.


No parking is required for a JADU. Certain jurisdictions require that JADU applicants replace any lost parking (due to garage conversion), but the City of Los Angeles does not require replacement parking.


Unlike ADUs, which often need to have separate utility meters and/or connections, a JADU's gas, water, and sewer connections can be hooked directly up to the main house. Additionally, a single water heater can serve both the main house and the JADU, which can be a huge cost savings. However, the JADU cannot share an HVAC system with the main house, so you will still need a dedicated ductless mini-split head and condenser for the unit.

Can I build a JADU?

If you own a single-family home in California, yes!

Homeowners may build one (attached or unattached) ADU and one (attached) JADU on their property.

Why build a JADU?

There are many compelling reasons for adding a JADU. Like full-size ADUs, junior accessory dwelling units can be legally rented out for supplementary income (though LA requires a minimum 30-day rental period).

Because utilities can be shared with the primary dwelling, homeowners can save money by building a junior accessory dwelling unit rather than a full one. Separate utility connections require trenching, which can be costly.

JADUs are ideal for visiting guests, live-in nannies, caretakers, or extended family members. The attached nature of the JADU allows for integration into the main house while maintaining some privacy.

What are the drawbacks?

Here are a few things you’ll want to take into consideration before adding a JADU:

Owner occupancy

First, a junior accessory dwelling unit requires an owner occupancy deed restriction. This means you can only rent out your JADU if you live in the existing house as your primary residence (alternatively, you can live in the JADU and rent out the main house).

Size limit

Junior accessory dwelling units are limited to 500 square feet, which may be too small for some homeowners’ needs. Additionally, the JADU must be created from existing space within the home, and you can’t build an addition to increase the amount of space available. This provision makes certain homes better suited to JADU development than others.

Parking replacement

If you choose to convert your garage into a junior ADU, you may need to replace parking. This can be a deterrent for some would-be JADU applicants.

Single-family only

Because junior accessory dwelling units may only be built within single-family homes, owners of multifamily properties will need to choose an ADU over a JADU.

Does Otto design and build JADUs?

Yes, Otto can create a beautiful custom JADU tailored to your home. Otto’s architects have extensive experience designing for small floor plans, efficiently maximizing all available space to make every square foot count.

If you want to build a JADU in your LA-area home, contact Otto today for a free consultation.

Want more ADU info?
Get our free guide!

Oops! Something went wrong while submitting the form.