Junior ADU (JADU) Builders in the Bay Area
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What Is a JADU?
A junior accessory dwelling unit (JADU) is a small, independent living space of up to 500 square feet created inside an existing single-family home. It is usually carved out of a bedroom or other existing space. Under California law, a JADU needs its own exterior entrance and at least an efficiency kitchen, and it can share a bathroom with the main house.
Because a JADU uses space you already have, it is often the fastest and least disruptive way to add a rentable or family unit to your property.
JADU vs. ADU
- Size: a JADU is capped at 500 sq ft. A full ADU can usually be 850 to 1,200 sq ft, depending on the city.
- Location: a JADU sits inside the existing home. An ADU can be detached, attached or a conversion.
- Kitchen and bath: a JADU needs an efficiency kitchen and may share the main home’s bathroom. An ADU has its own full kitchen and bathroom.
- Owner occupancy: with a JADU, an owner must live in either the main home or the JADU. ADUs generally have no owner-occupancy rule.
- Parking: no extra parking is required for a JADU.
A single-family lot can generally have both: one JADU plus one ADU. See our Bay Area ADU builders page for full ADUs.
Process
Our ADU Process
Step 1
Initial Consultation
We begin with a thorough initial consultation to understand your needs, assess your space, and discuss your vision, budget, and timeline.
Step 2
Planning and Design
At Axiom Renovation, we understand that the planning and design phase of an ADU project is crucial to its success. Our dedicated project managers will work closely with you to understand your goals, design ideas and budget for the project.
Step 3
Material Selection
We guide you through selecting high-quality materials that fit your design and budget, ensuring durability and aesthetic appeal.
Step 4
Demolition and Preparation
Careful demolition and preparation work are performed to ready the space for construction, minimizing disruptions and ensuring a clean work environment.
Step 5
Construction and Installation
Our skilled craftsmen handle the construction phase, including obtaining permits, scheduling appointments, and the actual construction and installation with precision, building the new space according to the approved design.
Step 6
Electrical and Plumbing Work
Licensed professionals conduct all electrical and plumbing work, ensuring everything is up to code and seamlessly integrated into the new ADU.
Step 7
Painting and Finishing
We pay close attention to detail during the painting and finishing stage, ensuring all surfaces are properly prepared and beautifully finished.
Step 8
Fixture and Appliance Installation
We expertly install all fixtures and appliances, ensuring they function correctly and fit perfectly with the overall design.
Step 9
Final Touches and Clean-Up
Final touches are added, and a thorough clean-up is performed, leaving your new space pristine and ready for use.
Step 10
Final Walkthrough and Client Satisfaction
We conduct a final walkthrough with you to ensure every detail meets your expectations and address any remaining concerns, ensuring your complete satisfaction.
What Goes Into Building a JADU
Most JADU projects are interior conversions, but they still involve real construction:
- A new exterior door, and often new windows that meet egress rules
- Fire separation between the JADU and the main house where required
- Plumbing and electrical for the efficiency kitchen, and a bathroom if you want one
- A check of your electrical panel capacity, which sometimes needs an upgrade
- A recorded deed restriction, which most cities require before they issue the permit
We handle the design, the permit set, the city submittal and the construction, so you have one contractor from start to finish.
Who a JADU Works For
Homeowners usually build a JADU to house a parent or adult child, to give a caregiver or nanny a private space, or to rent a room-sized unit with its own entrance. Many JADUs and ADUs must be rented for at least 30 days at a time, so they are a long-term rental rather than a short-term one.
Frequently Asked Questions
What is a JADU?
A junior accessory dwelling unit (JADU) is a living space of up to 500 square feet created inside an existing single-family home, with its own exterior entrance and at least an efficiency kitchen.
How big can a JADU be?
California law caps a JADU at 500 square feet, and it must be located within the existing single-family home.
Does a JADU need its own bathroom?
No. A JADU can share a bathroom with the main home. If it does, it needs an interior connection to the main house.
Do I have to live on the property to have a JADU?
Yes. An owner must live in either the main home or the JADU, and most cities record a deed restriction that says so.
Does a JADU need parking?
No. California law does not require additional parking for a JADU.
Can I have a JADU and an ADU on the same lot?
Generally yes. A single-family lot can typically have one JADU plus one ADU. Local rules vary, so we confirm what your city allows during the site assessment.