top of page

JADU vs ADU: Key differences between JADU and ADU

A junior accessory dwelling unit (JADU) is a home addition type built and connected to your existing house. According to California State regulation, a maximum of 500 square feet is allowed on your property. Also, regulations do not allow adding more than 150 square feet to your property. Essentially, it's a converted part of your home that's designed to be a smaller version of a regular accessory dwelling unit (ADU).

ADU 22175 Dolores  Atlas Construction
ADU home addition in 140 Arrayo grand way

Difference in Size

The maximum size allowed for Junior Accessory Dwelling Units (JADUs) is 500 square feet, while ADUs can be up to 1,200 sq ft, depending on the rules of your area. Generally, 500 sq ft is sufficient to meet the needs of most homeowners, especially with good design. However, unlike ADUs, JADUs cannot add an extra 150 sq ft for ingress and egress during conversions. This means you can only use the existing space you plan to convert.

Unlike JADU, ADUs can have sizes ranging from 300 to over 1,200 square feet. However, if attached to the primary residence on a property, they must not exceed half of the square footage of the existing home.

ADU Kitchen vs JADU Kitchen

When it comes to the kitchens in Junior Accessory Dwelling Units (JADUs) and Accessory Dwelling Units (ADUs), there are some notable differences in terms of their size and complexity. To begin with, a JADU kitchen is typically referred to as an "efficiency kitchen" and is designed to provide basic cooking facilities. This means that it must contain a food preparation counter, storage cabinets, and appliances that require no more than 120V of electricity. Because of this, a JADU kitchen is intended for simpler cooking tasks and usually features smaller appliances.

On the other hand, an ADU kitchen is more comprehensive and resembles a traditional kitchen in most ways. It requires facilities for cooking, food preparation, running water, and cabinetry, making it much more capable of handling complex cooking and food preparation tasks. With more space and more advanced appliances than a JADU kitchen, an ADU kitchen is designed to meet the demands of a full kitchen in a separate dwelling unit.

Kitchen Sink
Home Deck

Difference in cost

The comparison between an Accessory Dwelling Unit (ADU) and a Junior Accessory Dwelling Unit (JADU) lies in their cost structure, which is determined by differences in size, requirements, and construction implications. To briefly compare the two, JADUs are smaller than ADUs, with a maximum size of 500 square feet.

Due to their smaller size and simpler requirements, JADUs can be significantly less expensive, costing between $50,000 to $90,000. On the other hand, ADUs can range from $200,000 to $400,000 in California and most other areas in the US.

The difference in Renting out the ADU and JADU

If you're thinking about adding a JADU (Junior Accessory Dwelling Unit) to your home, there are several ways you can use the newly renovated space. You can live in it yourself, house in-laws there, or generate rental income through tenants. However, it's crucial to note that many jurisdictions require the house to be owner-occupied if you decide to rent out your JADU. This means that you'll need to live in the rest of your home while a tenant is renting the JADU.

California's new law, effective in 2022, states that Accessory Dwelling Units (ADUs) are not required to be owner-occupied. This means that local agencies cannot mandate ADU owners to live in either their ADU or their main house if they are renting either. You can rent out both your ADU and main house as long as you are not renting out a JADU. However, if you are renting out a JADU, you are required to live in the primary residence.

Renting out an ADU or JADU for less than 30 days is generally not allowed under California law. However, homeowners can apply for an exception by meeting certain requirements and specifying the number of days they occupy their home. If you want to rent out a JADU, you must live in the rest of your home. If you're renting out an ADU, you don't need to live in either the ADU or the main house. Make sure to comply with California law and obtain necessary permits to rent out your unit(s).

Refer to ADU Handbook prepared by California Department of Housing and Community development to learn more. 

Empty apartment
ADU by Atlas General Construction

JADU limitations

In some local areas, regulations limit the installation of 220-volt kitchen appliances, preventing the use of conventional ranges. Additionally, these areas may also restrict the use of full-sized refrigerators in a kitchenette. As a result, a Junior Accessory Dwelling Unit (JADU) under such constraints might serve more as a leisure area than a separate living unit, particularly if there’s a shared primary bathroom. However, this may not be an issue for certain renters, like those who are often traveling and see the JADU as a temporary residence, students, or a single elderly person who regularly joins you for meals, akin to the traditional concept of a “granny flat.”

Given that JADUs only need to meet minimal criteria, such as having an independent entrance and a kitchenette, they can be a quick and easy way to expand living space. Yet, this might be limiting when leasing to someone desiring a more equipped kitchen or a private bathroom. Some might consider The JADU a compromise, but it remains a practical choice.

For personalized advice on understanding the nuances between JADUs and ADUs and to delve deeper into your specific requirements, don't hesitate to schedule a one-hour complimentary consultation with Atlas General Construction. Let our experienced team guide you through creating the ideal additional living space tailored to your unique preferences and lifestyle.
Refer to the  link to learn more about Home additions


bottom of page