Junior ADU (JADU) Guide for Sacramento

What is a Junior ADU (JADU)?

A JADU is carved out of your home's existing footprint — no new foundation, no addition. It's capped at 500 sq ft, must have its own exterior entrance, and needs an 'efficiency kitchen' (sink, cooking appliance, counter). It can have its own bathroom or share one with the main house. Because it reuses existing structure, it's the lowest-cost legal unit you can add.

See also:Junior ADU (JADU) builder · JADU (glossary)

Does a JADU have an owner-occupancy requirement?

Yes — this is the single biggest difference from a standard ADU, and it's the rule that decides whether a JADU fits your plan. While California suspended owner-occupancy for standard ADUs permitted on or after January 1, 2020, a JADU still requires the owner to live on the property, in either the main house or the JADU itself. You can't build a JADU and then move away and rent both units; one of them has to remain your residence.

That requirement exists because a JADU is carved out of the existing single-family home rather than built as a fully independent dwelling, so the law treats the home and the JADU as one owner-occupied property. For a Sacramento owner who plans to live on site — including most multigenerational and house-hacking setups — the rule is a non-issue, since you're living there anyway. But if your goal is to rent both units and live elsewhere, a standard ADU is the better fit, because it carries no owner-occupancy requirement.

See also:Owner-occupancy (glossary)

Can you build a JADU and a regular ADU on the same lot?

Yes. A single-family lot in the City of Sacramento can hold both one standard ADU and one JADU — three units total once you count the main house. That combination is one of the most powerful ways to maximize a lot, because the JADU reuses interior space you already have (from about $85,000) while the standard ADU adds a fully independent unit that rents for more. Built together, they can turn a single-family parcel into a small income property without buying any land.

The one rule to plan around is owner-occupancy: even when you pair the two, the JADU still requires the owner to live in either the main house or the JADU itself. If your goal is to rent every unit and live elsewhere, the standard ADU carries no such requirement (for units permitted after January 1, 2020), so most build-out-the-lot strategies put the owner's residence in the JADU or main house and rent the standard ADU.

What does a JADU cost in Sacramento?

JADUs start around $85,000 and run roughly $200–$320 per square foot (2026 Sacramento-region market data), which makes them the cheapest legal unit you can add — below even a garage conversion's $95,000 starting point, because a JADU reuses interior space rather than rebuilding a garage shell. The cost lives almost entirely in two line items: adding the required separate exterior entrance and bringing in the efficiency kitchen (a sink, a cooking appliance, and counter space). A bathroom can be its own or shared with the main house, and sharing one keeps the budget down.

The single biggest swing factor is plumbing distance. Converting a bedroom or bonus room that already sits next to existing water and waste lines is the cheapest scenario; running new lines across the house to reach the new kitchen and bath is what pushes a JADU toward the top of the range. JADUs under 500 sq ft also stay well under the 750 sq ft impact-fee threshold, so local impact fees are waived (per California HCD).

See also:What an ADU costs in Sacramento

How does a JADU compare to a standard ADU?

A JADU and a standard ADU solve different problems. The JADU is smaller, cheaper, and tied to your home and your presence on the property; the standard ADU is larger, fully independent, rents for more, and carries no owner-occupancy requirement (for units permitted after January 1, 2020). The table lines up the trade-offs that usually decide it.

See also:Sacramento ADU rules & permits

What does it take to convert a bedroom into a JADU?

Most JADUs are a bedroom or bonus room converted in place, so the work is lighter than a new build — but it's still permitted as a dwelling. The cost lives almost entirely in two things: adding an exterior entrance and bringing in the efficiency kitchen. A room already next to existing plumbing is the cheapest scenario; running new water and waste lines across the house is what pushes the budget up.

• A separate exterior entrance for the JADU (a required feature)
• An efficiency kitchen: sink, a cooking appliance, and counter space
• A bathroom — its own, or shared with the main house to save cost
• Possible electrical and plumbing runs depending on where the space sits
• A building permit; a JADU is new dwelling space even inside existing walls

See also:What an ADU costs in Sacramento

When is a JADU the right choice?

Choose a JADU when you want the lowest-cost unit, you're comfortable living on the property, and you have a convertible interior space — a spare bedroom, a bonus room, or an attached garage area. If you want maximum rent, a fully independent unit, or the ability to move out, look at a detached or garage-conversion ADU instead. And remember you don't always have to choose just one: a single-family lot can hold both a JADU and a standard ADU, so a JADU can be the first, cheapest step toward a fully built-out lot.

See also:Garage conversion ADU · Detached ADU