Junior ADU

Junior ADU conversion across San Diego County

A junior ADU converts an attached garage into an independent living space up to 500 square feet that shares plumbing and an entry with the main home, qualifying under California JADU law with lower permit fees and a simpler plan check process than a full ADU. We connect San Diego County homeowners with insured local crews that handle the full conversion from permit drawings through framing, insulation, drywall, flooring, and kitchen and bathroom connections. Garage Convert SD is a referral service, insured but not licensed, cslb.ca.gov.

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Interior of an attached garage being converted to a junior ADU in San Diego County with framing, insulation, and a new kitchenette rough-in underway

What's included in this service?

JADU-specific permit drawings confirming the unit is within 500 square feet and contained within the existing structure
Garage door removal and wall infill with framing, insulation, drywall, and exterior finish to close the opening
Kitchenette rough-in connecting to the main home plumbing with an efficiency sink and countertop cooking setup
Bathroom connection options sharing the main home bath or adding a half-bath within the JADU footprint
Insulation, drywall, and fire-rated assemblies meeting California JADU code requirements
Flooring, interior finish, and final permit inspection sign-off

When do you need this service?

Your attached garage qualifies for a JADU and you want lower permit costs than a full ADU requires
A family member needs a private living space with their own kitchenette without the expense of full separate plumbing
You want to add a rental unit but your budget does not support a full ADU conversion with a dedicated bathroom and separate entry
Your property has an attached garage and limited setback room for a detached ADU or new construction
You want to complete the conversion faster than a full ADU and get the unit occupied sooner

What do homeowners ask about Junior ADU?

What is the difference between a JADU and a full ADU?

A JADU (junior accessory dwelling unit) is limited to 500 square feet, must be within an existing attached structure like an attached garage, and can share a bathroom with the main home. A full ADU has no size cap up to California limits, can be detached or attached, and requires its own bathroom and kitchen. JADUs have lower permit fees but more restrictions on rental use and cannot be sold separately from the main home.

How much does a junior ADU conversion cost in San Diego?

A junior ADU conversion in San Diego County typically runs $50,000-$90,000 depending on whether you share the main home bathroom or add a half-bath, the kitchenette scope, and the interior finish level. The on-site estimate from the crew confirms the price before any work starts.

Can I rent out a junior ADU in San Diego?

Yes, with a restriction. California JADU law requires the property owner to live on-site, either in the main home or in the JADU itself, while the other unit is rented. You cannot rent both the main home and the JADU and live off the property. A full ADU does not carry this restriction.

Does a junior ADU need its own bathroom?

No. A JADU can share a bathroom with the main home if the unit has interior access to it. If you want a private bathroom within the JADU footprint, a half-bath can be added within the 500 square foot limit. The crew confirms the plumbing scope at the on-site estimate.