Junior ADU (JADU) Guide for Sacramento
Updated June 12, 2026 · Upside ADU
Quick answer
A Junior ADU (JADU) is an accessory unit of up to 500 square feet created within the existing walls of a single-family home, often a converted bedroom. It needs its own entrance and a small kitchen, may share a bath with the main house, and keeps an owner-occupancy requirement. JADUs are the cheapest ADU type, from about $85,000.
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 key difference from a standard ADU. While California suspended owner-occupancy for standard ADUs permitted after January 1, 2020, JADUs still require the owner to live in either the main house or the JADU. If you want to rent both units and live elsewhere, a standard ADU is the better fit.
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 with the main house. That combination is a powerful way to maximize a lot, though the JADU's owner-occupancy rule still applies.
What does a JADU cost in Sacramento?
JADUs start around $85,000 and run roughly $200–$320 per square foot, depending on whether the space already has plumbing nearby and how much of a kitchen and bath you add. Converting a bedroom adjacent to existing plumbing is the cheapest scenario.
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.
Junior ADU vs. standard ADU (Sacramento, 2026)
| Factor | Junior ADU (JADU) | Standard ADU |
|---|---|---|
| Max size | 500 sq ft | Up to 1,200 sq ft detached |
| Built where | Inside existing walls | Detached, attached, or garage conversion |
| Owner-occupancy | Required | Not required (permitted after Jan 1, 2020) |
| Typical cost | From ~$85,000 | From ~$95,000 (conversion) to $500,000 |
| Kitchen | Efficiency kitchen OK | Full kitchen |
| Bathroom | Can share with main house | Own bathroom |
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
This guide is general information, not legal or tax advice. ADU rules change often and vary by city — we confirm the current requirements for your jurisdiction during your free feasibility check.
Sources & references
- Accessory Dwelling Units — official guidance — California Dept. of Housing & Community Development (HCD)
- ADU resources & pre-approved plans — City of Sacramento — Community Development
External links open official government and lender resources. Construction price and rent figures reflect 2026 Sacramento-region market conditions; confirm current rules and fees with your jurisdiction.