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Patrice Peterson
★★★★★9 months ago
We hired Jimmy for a garage to ADU conversion project. The project was completed quickly, with diligent work from Jimmy's team, resulting in a finished product that exceeded our expectations!
ADU Builder in Chino, CA
J.O. Construction is an ADU builder based in Chino that designs, permits and builds accessory dwelling units: detached backyard units, garage conversions, units above a garage and multi-family ADUs. We have finished ADUs from 700 to 893 sq ft in Fontana, Riverside, Rancho Cucamonga, Santa Ana and San Clemente, and most of our Google reviews come from ADU owners. Call (951) 436-6568.
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ADUs we have built, newest first
Real jobs, newest first. Dates are the month we posted each stage on our Instagram.
A duplex ADU in San Clemente: two rental units on one lot
A San Clemente property and a plan for two units on it, designed to get the most out of the lot, with interior designer 8a Interiors.
A 730 sq ft detached ADU in Fontana with 2 bedrooms and 2 baths
Two bedrooms, two bathrooms and a full kitchen in 730 sq ft, in a Fontana backyard.
A 700 sq ft ADU above the garage in San Clemente
A San Clemente lot where the new unit went on top of the existing garage: 700 sq ft, two bedrooms and one bath.
A multi-family ADU in Fontana, pour to finish line in about 4 months
A multi-family ADU project on a Fontana property.
An 893 sq ft ADU and pool house in Fontana, built in two phases
A Fontana backyard with a pool.
A historic garage conversion ADU in Floral Park, Santa Ana
A Tudor style garage in Santa Ana's Floral Park historic neighborhood.
A custom ADU in Rancho Cucamonga with a pocket corner door
A fully custom ADU in Rancho Cucamonga: a living room that opens to the yard at the corner, white oak details and a custom concrete floor.
An 800 sq ft detached ADU in Riverside, built in about 4 months
A Riverside backyard with room for a separate unit, and interior designer 8a Interiors on the job from ground breaking.
What is included
- Detached ADUs, garage conversions and above-garage units
- Multi-family ADUs for investors
- Plans with a designer or your architect
- The city submittal
- Trenching, slab and framing
- Rough trades and city inspections
- Finishes through the final
The job, in three frames
How the job runs with J.O. Construction, in the order it happens.
Step 1: Plans and the city
We site the unit, work out the plans with a designer and send them to the city.
Step 2: Slab and frame
Trench for utilities, pour the slab, then framing and the roof.
Step 3: Finishes and final
Rough trades and inspections, then the kitchen, bath and the final sign-off.
Which kind of ADU fits your lot
| Type | What it uses | One we built | Good when |
|---|---|---|---|
| Detached ADU | New slab, walls and roof in the yard | 730 sq ft, 2 bed, 2 bath, Fontana (Mar 2026) | You have yard space and want the most privacy |
| Garage conversion | The garage slab, walls and roof you already have | Historic Tudor garage, Floral Park, Santa Ana (Apr to Aug 2025) | The garage is used for storage, not cars |
| ADU above the garage | The garage footprint, built up a story | 700 sq ft, 2 bed, 1 bath, San Clemente (Jan 2026) | The yard is small and you want to keep parking |
| Multi-family ADU | Two or more units on one property | Duplex ADU, San Clemente (Jul 2026) | You own a rental property and want more units |
Garage Conversion in Chino
Converting a garage is the fastest way to add a unit, since the slab, walls and roof are already there. We converted an 1,100 sq ft garage into a two-bed, two-bath casita, and a historic garage in Santa Ana's Floral Park. More on garage conversions.
Detached ADU in Chino
A detached unit gives the most privacy and the most rent. Ours run from 730 to 1,200 sq ft, with full kitchens, one or two baths and laundry. We built an 800 sq ft backyard unit for a client who then sent us her neighbors. More on detached ADUs.
Above-Garage ADU in Chino
When the lot is tight, the unit goes over the garage. We finished a 700 sq ft, two-bed, one-bath ADU above a garage in San Clemente, and have another going up there with corrugated metal and cedar siding. More on above-garage ADUs.
Multi-Family ADU in Chino
Investors hire us to add more than one unit at a time. We finished a duplex ADU in San Clemente and a multi-family ADU project in Fontana, both designed to get the most rentable space out of the lot. More on multi-family ADUs.
How we build an ADU: the decisions that matter
The lot and the city come first. Before plans go in, we check setbacks, utility locations and where the trench for sewer and power will run. That is what keeps a design from changing halfway through plan check.
Designers on the job from ground breaking. Several of our ADUs were built with interior designer 8a Interiors from the first day, including the 800 sq ft Riverside unit and the Fontana pool house. If you need an architect for the floor plan, we can refer one; one client wrote that we "referred the architect who drew up my floor plans." Or we run the whole thing as design-build, plans and build under one contract.
Historic and special rules handled with the city, not around it. On the Santa Ana garage conversion in the Floral Park historic district we coordinated with the city historic department from day one, which kept the job on time.
Products picked for the job. The Rancho Cucamonga ADU has a Windor Systems pocket corner door that opens the living room to the yard, set in February 2025 before drywall.
You see every stage. Slab, framing, rough plumbing and electrical, stucco and finishes all go up on our Instagram while the job runs.
How long an ADU takes with us
On our recent jobs, construction ran about 4 months for the 800 sq ft detached ADU in Riverside (ground broken Oct 2024, finished Feb 2025) and for the Santa Ana garage conversion (Apr to Aug 2025), and about 6 months for the 700 sq ft unit above a garage in San Clemente (Jul 2025 to Jan 2026). Plans and the city permit come before that. The step-by-step version is on our ADU timeline page.
ADU rules in Chino
State law sets the floor for every city: a city has to act on a complete ADU application within 60 days, and ADUs of 750 sq ft or less pay no impact fees. Chino adds its own standards in its zoning code and offers pre-approved detached ADU plans. The full list, with the code sections and the date we checked them, is on our Chino ADU rules page.
What moves the price of an ADU in Chino
Square footage, detached versus a conversion, how far the sewer, water and power lines have to run, and the finish level. A garage conversion reuses the slab and walls, so it usually costs less than a new detached unit of the same size. We price your unit from the plans and put it in writing.
Is this the right call for your project?
Call us for this when
- You want rental income or room for family on the lot you own
- There is space in the yard, a garage you do not park in, or room to build up
- You want one builder handling the design, the city and the build
Pick something else when
- The garage is the space you have: see garage conversions
- The yard is tight: build over the garage
- You own a rental property and want more than one unit: multi-family ADUs
After the final inspection: keeping it in shape
- 1
Keep the unit's own paperwork
Permit card, plans and the address the city assigned. A tenant or a buyer will ask.
- 2
Service its HVAC separately
The ADU has its own system. Change its filter on its own schedule.
- 3
Walk it before each new tenant
Check under sinks, around the shower and at the windows between tenants. Small leaks found early stay small.
Before you call
What moves the price
- Square footage
- Detached versus a conversion: a garage conversion reuses the slab and walls
- How far utilities have to run
- The finish level
- Priced from the plans and put in writing
ADU Builder services near Chino
Recent work from our crews
More on our Instagram, where we post each stage as it happens.
Return to J.O. Construction, Chino.
What clients sayReal words from Google, unedited.
A
Antonio Reyes
★★★★★a year ago
Thank you Jimmy for taking on our project for our ADU build. It was a pleasure from beginning to end to work with you guys. Always very transparent and there to answer any phone calls or questions.
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Bert MTZ
★★★★★2 years ago
ADU 730sf in Fontana, two bedrooms two bathrooms, complete kitchen. … Provided a good service and choices with the option of getting upgrades. Communication was key and Jimmy made it easy to reach out and listen to concerns or changes.
ADU questions owners ask us
How much does it cost to build an ADU?
It depends on size, detached versus conversion, utility runs and finishes. We have not published a price range yet because we only post numbers from our own finished jobs. We price your unit from the plans, in writing, before anything starts.
How big can an ADU be in Chino?
State law lets a detached ADU be up to 1,200 sq ft, and a city has to allow at least 800 sq ft with 4 ft side and rear setbacks. The exact limit on your lot depends on the zoning and the main house. Our Chino ADU rules page has the details.
How long does an ADU take to build?
Construction ran about 4 to 6 months on most of our recent ADUs, after the permit. A city has 60 days to act on a complete ADU application. One client wrote that her 800 sq ft unit "stayed on track very close to the schedule we had discussed."
Do you handle ADU plans and permits?
Yes. We work with designers and architects on the plans and handle the city submittal, corrections and every inspection through final.
Is a garage conversion cheaper than a detached ADU?
Usually, for the same size, because the slab, walls and roof already exist. One owner hired us to turn an 1,100 sq ft garage into a two-bed, two-bath casita.
Can I rent out my ADU?
Yes. Many of our clients build to rent. State law does not let a city require you to live on the property for an ADU, and rentals must be longer than 30 days. Details on our ADU rules page.
Room for a unit? Let's look.
Tell us about the yard or the garage. We will tell you what fits.
Mon to Fri, 7 AM to 5 PM
Start a conversation
Thinking about a project? Let's talk.
Answer a few quick questions and Jimmy will call you back to talk it through. No pressure and no obligation.
- Jimmy runs your job from the first call to the final inspection
- Licensed and bonded, CA #1057456
- Design, permits and construction under one roof
Rather just talk to someone? Call (951) 436-6568
Mon to Fri, 7 AM to 5 PM