JADU Builder in Sacramento: Laws, Cost & Timeline (2026 Guide)
- Result Construction
- Jan 14
- 6 min read
Table of Contents
Hey, so you’re thinking about adding a JADU — that smaller, inside-the-house secondary unit — to your Sacramento home. Maybe it’s for your parents so they can stay close without taking over the whole place, or for your grown-up kids who need their own corner but still want to be around, or even just to get a little rental income that actually helps with the mortgage. Either way, you’re smart to look into this early because JADUs are one of the easiest and cheapest ways to add living space right now.
I’ve seen a bunch of these projects happen around here — some families in Elk Grove, Roseville, Folsom, Citrus Heights, Rancho Cordova, West Sac, Natomas, Carmichael, Fair Oaks, and even out toward Vacaville, Davis, Woodland, Rocklin, Lincoln, Vallejo, Antioch — and the ones that go smooth usually start with the same question: “What do I actually need to know about laws, costs, and how long this will take?”
Let’s just walk through it like we’re sitting on the porch talking — no fancy stuff, just the real info.
What a JADU Actually Is (and Why People Call It a Junior ADU)
A JADU is basically a mini version of a regular ADU, but it has to be built completely inside your existing single-family home. No new detached building, no garage conversion to a separate structure — it’s carved out of space you already have, like turning a basement, bonus room, or large bedroom into its own little apartment.
The official California rules (Government Code § 65852.22 and HCD guidelines) say:
Max 500 square feet
Has to have an efficient kitchen (small sink, fridge, microwave , or cooktop, no full stove in some cities)
Can share the main house bathroom or have its own
A separate entrance is nice, but not always required
Owner must live in either the main house or the JADU (this rule is still active in 2026)
Because it’s inside the house, most cities and Sacramento County treat JADUs as simpler than full ADUs — fewer permits, less red tape, and usually faster approval.
A buddy of mine in Carmichael did this for his mom a couple years back — converted the downstairs guest suite into a JADU. She has her own kitchenette, her own TV area, and her own door to the side yard. He still sees her every day, but she has her privacy. Cost him way less than a backyard unit and was done in under 4 months.
JADU Laws & Rules in Sacramento (2026 Update)
California has made JADUs pretty straightforward, but Sacramento County and the City have a few local twists you need to know.
Key JADU rules right now:
Max size: 500 sq ft (some cities enforce strictly, some are more flexible on measurement)
Kitchen: Efficiency only — no full oven/range in most cases (microwave + cooktop is standard)
Bathroom: Can share the main house bathroom or add a small one inside the unit
Owner occupancy: You (the owner) must live in either the primary house or the JADU — this is stricter than regular ADUs
Parking: No extra parking required for JADUs in most cases
Permitting: Usually ministerial (no public hearing), 30–60 days max
Sacramento County and the City both allow JADUs on any single-family lot that already has a primary home. No minimum lot size, no extra setbacks, no height issues because it’s inside.
To check your house specifically, use the County Online Map Viewer or the City’s ADU/JADU portal — put in your address and it’ll show you if there are any weird overlays.
For the full eligibility picture, our post on can I build an ADU on my property covers both ADUs and JADUs with the same tools.
Get JADU Cost Estimate
Thinking a JADU might be perfect for your house? Call us & we’ll look at your space and give you a real cost number, no sales pressure.
How Much Does a JADU Cost in Sacramento Right Now?
JADUs are usually the cheapest way to add a secondary unit because you’re not building new foundation or exterior walls. In 2026, most Sacramento JADUs end up between $80,000 and $150,000, depending on how much plumbing/electrical you need and what finishes you pick.
Typical breakdown:
Basic conversion (using existing bathroom, minimal kitchenette) — $80,000–$110,000
Full conversion (new bathroom inside, better kitchen, flooring) — $110,000–$140,000
High-end finishes (new windows, nice cabinets, smart features) — $140,000–$180,000
Biggest cost drivers:
Adding a new bathroom or moving plumbing — adds $15k–$30k
Kitchenette quality — basic vs. nicer appliances/fixtures
Flooring and drywall work — cosmetic stuff adds up fast
Permits — usually $2,000–$6,000 (lower than full ADUs)
One family I know in Natomas converted an oversized laundry room + storage into a JADU for their son. They kept the existing bathroom, added a small kitchenette, and new flooring — total around $95k. Now he pays them rent, and they’re both happy.
For a quick sense of your own numbers, Result Construction has a custom ADU/JADU Calculator on their site — just put in approximate size and your city and it gives a realistic range.
Start My JADU Project
If a JADU sounds like the right fit for your family, let’s talk. We’ll help you figure out what’s possible in your house and a real budget.
Typical JADU Timeline in Sacramento (2026)
Because JADUs are inside the existing home, they usually go faster than detached or garage units.
Rough timeline most families see:
Planning & design — 2–4 weeks (pre-approved layouts speed this up)
Permitting — 30–60 days (ministerial approval, no public hearing)
Construction — 2–4 months (mostly interior work)
Final inspections & occupancy — 1–3 weeks
Total: 4–8 months from start to move-in day for most projects.
The fastest one I’ve seen was in Roseville — they reused almost everything and had it done in about 3.5 months. The slowest was a complicated plumbing reroute in a 1950s house — took closer to 9 months.
For the full step-by-step process, check our guide on how to build an ADU — it covers JADUs too Get ADU Cost Estimate
Want to know what a JADU would cost and how long it would take on your property? Call us, we’ll give you straight answers based on your house.
Why Pick a Local JADU Builder in Sacramento?
A lot of people try to save money by going with the lowest bid or a general contractor who says they can do JADUs. That works sometimes, but most of the time it leads to delays, surprise costs, or work that doesn’t meet code.
A true local JADU builder knows:
Sacramento County vs City differences
Which inspectors are strict on what
How to submit complete packages the first time (avoids 30-day resubmits)
Realistic pricing so you don’t get hit with change orders
How to make the unit feel nice without blowing the budget
One family in Fair Oaks hired a cheap out-of-area guy — ended up paying almost 40% more because of permit mistakes and rework. A local specialist would have caught those early.
Start My JADU Project
If you’re ready to move forward with a JADU, give us a call & we’ll walk you through what’s realistic for your home and get a plan started.
For design inspiration that works well inside Sacramento homes, take a look at our ADU models — several are JADU-friendly layouts.
Frequently Asked Questions
1. What is a JADU in Sacramento?
A Junior Accessory Dwelling Unit (JADU) is a small secondary unit (max 500 sq ft) built completely inside your existing single-family home — like a converted bedroom or basement with its own kitchenette.
2. What are the main JADU laws in Sacramento?
Max 500 sq ft, efficiency kitchen, can share bathroom, owner must live in the house or JADU, no extra parking usually required, 30–60 day permitting.
3. How much does a JADU cost in Sacramento in 2026?
Typical range is $80,000–$150,000 — cheaper than full ADUs because it’s interior work only. Basic conversions start lower, nicer finishes push higher.
4. How long does it take to build a JADU?
Usually 4–8 months total — planning 2–4 weeks, permitting 30–60 days, construction 2–4 months, final inspections 1–3 weeks.
5. How do I find a good JADU builder in Sacramento?
Look for someone who specializes in ADUs/JADUs, has recent local projects, gives clear itemized quotes, and communicates well. Ask for references and proof of local permitting experience.