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ADU Rules in Chino, CA (2026): what state law and the city allow

Last checked Oct 15, 2026

Yes, you can build an ADU on a single-family lot in Chino. Since January 1 2026, state law allows a converted ADU, a junior ADU (JADU) and a new detached ADU on the same single-family lot (Gov. Code 66323). Chino's own ADU section, Municipal Code 20.11.020, was last amended in July 2022 and still says one ADU and one JADU; where a local rule conflicts with state ADU law, state law controls (Gov. Code 66316). Below is each rule side by side, with the code section, and what it means on a real job. To check your own lot, call (951) 436-6568 or the Chino Planning Division at (909) 334-3253.

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State law and Chino's code, side by side

Rule	State law	Chino code (20.11.020, Ord. 2022-010)
Units on a single-family lot	Any combination of one converted ADU, one JADU and one new detached ADU; the detached one may be capped at 800 sq ft in that combination (66323(a))	One ADU and one JADU
Detached size	Up to 1,200 sq ft (66314(d)(5)). A city must allow at least 850 sq ft, or 1,000 sq ft with more than one bedroom (66321(b)(2)), and always an 800 sq ft unit with 4 ft setbacks (66321(b)(3))	50% of the house or 1,200 sq ft, whichever is less; a detached unit up to 80% of the house's floor area; 800 sq ft guaranteed
Attached size	Up to 50% of the house (66314(d)(4))	Same 50% / 1,200 sq ft limit
Setbacks	No more than 4 ft side and rear; none for a conversion in the same footprint (66314(d)(7))	Flagged by the state in 2023 (see below)
Height	A city must allow at least 16 ft detached; 18 ft within half a mile walk of major transit, plus 2 ft to match the roof pitch; attached up to 25 ft or the zone's limit, whichever is lower (66321(b)(4))	1 story and up to 16 ft
Parking	At most 1 space per unit; none when a garage is converted or torn down (66314(d)(10), (11)); none at all within half a mile walk of transit, in a historic district, or for a unit inside the house (66322)	1 space per ADU with the state exemptions; no replacement parking for a garage conversion
Owner living on site	Not required for an ADU. For a JADU, only if it shares a bathroom with the house (66333)	Owner must live on site for any JADU
Renting it out	A city may require rentals of 30 days or longer (66315)	At least 31 days
Fire sprinklers	Not required unless the house needs them (66314(d)(12))	Not stated in 20.11.020
Design	Not covered on this page	Must match the main house

In October 2023 the state housing department (HCD) wrote to Chino that parts of this ordinance did not comply with state law, including the unit count, size and height limits and setbacks. We found no newer Chino ADU amendment in the code as published (Municode, Supplement 38, posted August 11 2026). The practical step: ask Planning how it applies the state rules to your address before you pay for plans, and we do that with you.

Junior ADUs (JADU)

A JADU is a unit of up to 500 sq ft built entirely inside the house; an attached garage counts as part of the house. It needs its own entrance and an efficiency kitchen, and you can have one per lot (Gov. Code 66313(d), 66333). Since January 1 2026 the owner has to live on the property only when the JADU shares a bathroom with the house; a deed restriction is recorded, rentals must run longer than 30 days, and no parking is required (66334). Chino's code allows JADUs only inside the house or an attached garage.

Fees on an ADU in Chino

Impact fees: none on an ADU of 750 sq ft or less; above that, only in proportion to the size of the main house (Gov. Code 66311.5(c)(1), renumbered from 66324 on January 1 2026). Utility connection: a converted unit inside an existing structure needs no new connection and pays no connection fee; other ADUs may be charged in proportion to size or plumbing fixtures (66311.5(d), (e)). School fees: units of 500 sq ft or less are exempt (Ed. Code 17620; HCD); above that, Chino's fee schedule lists $5.38 per sq ft, collected by the Chino Valley Unified School District before the permit. City fees: the building permit fee is based on project valuation and plan check is 75% of it (schedule effective July 1 2026). Fire review: $452 for an ADU at the Chino Valley Fire District.

The permit path in Chino, step by step

1. Plans go to the city. Chino offers free pre-approved detached ADU plans in studio, 1, 2 and 3 bedroom sizes, given at no cost in exchange for a signed hold-harmless statement; they still go through plan check, with what the city calls "a shorter turnaround period".

2. The city has 15 business days to say whether the application is complete and 60 days to approve or deny a complete one on a lot with an existing home, or it is deemed approved (Gov. Code 66317). If you file the ADU together with a new house, the city may wait to decide the ADU until it decides the house.

3. Chino's published plan check estimate is "4-5 weeks for the first review, and 1-2 weeks for the second and subsequent reviews" (Building Division FAQ, Rev 1/15/2020).

4. The Chino Valley Fire District reviews the ADU in "7 to 10 business days" and needs a fire flow report from your water provider. The city will not issue the building permit until the fire district approves.

5. Build and inspections. Inspection requests made before 3 pm are scheduled for the next business day. The permit expires after 180 days without progress, with one 180-day extension. How long the build takes on our jobs is on our ADU timeline page.

What these rules mean on a real job

Garage conversions: the parking rule is the one owners ask about first. State law and Chino's code both say a city cannot make you replace the garage parking when the garage becomes an ADU. We have turned an 1,100 sq ft garage into a two-bed, two-bath casita, and a historic Tudor garage in Santa Ana into a unit. More on garage conversions.

Special districts: in Santa Ana's Floral Park historic district we coordinated with the city historic department from day one, which kept that job on time. A historic district also removes the parking requirement under state law.

Building up: Chino's code still says 1 story and 16 ft, while state law requires cities to allow an attached ADU up to 25 ft or the zone's limit. If you want a unit above the garage, settle the height question with Planning first. We built a 700 sq ft unit above a garage in San Clemente.

Grants: the state's CalHFA ADU grant, up to $40,000, has been fully allocated since December 28 2023 and no new round is posted.

Sources

Every rule on this page comes from these, opened and read on the date shown.

California Government Code 66314, 66315, 66316, 66317, 66321, 66322, 66323 (as amended by SB 543 and AB 1154), leginfo, read Oct 15 2026
Government Code 66311.5 (fees, renumbered from 66324), leginfo, read Oct 15 2026
Government Code 66313 and 66333 (JADUs), leginfo, read Oct 15 2026
HCD ADU Handbook, updated March 2026, read Oct 15 2026
HCD findings letter on Chino's ADU ordinance, Oct 3 2023, read Oct 15 2026
Chino Municipal Code 20.11.020, Ord. 2022-010 (Municode, Supplement 38), read Oct 15 2026
City of Chino, Accessory Dwelling Units page, undated, read Oct 15 2026
City of Chino, pre-approved ADU program hold-harmless statement, read Oct 15 2026
City of Chino Building Division FAQ, Rev 1/15/2020, read Oct 15 2026
City of Chino building fee schedule, effective July 1 2026, read Oct 15 2026
Chino Valley Fire District ADU submittal guideline, undated, read Oct 15 2026
CalHFA ADU grant program, read Oct 15 2026

This guide supports our ADU builder page, where you can see every ADU we have built. Or go back to the J.O. Construction home page.

What clients sayReal words from Google, unedited.

GoogleReviews4.8★★★★★21 reviews See all reviews

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!

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.

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.

Questions owners ask us

How many ADUs can I build on my lot in Chino?

Under state law since January 1 2026, a single-family lot can have one converted ADU, one JADU and one new detached ADU (Gov. Code 66323). Chino's 2022 code still says one ADU and one JADU, so confirm with Planning for your address.

Do I have to live on the property?

Not for an ADU. For a JADU, only if it shares a bathroom with the main house (Gov. Code 66333). Chino's code still asks the owner to live on site for any JADU.

Do I need to replace my garage parking if I convert it?

No. State law and Chino's code both say a city cannot require replacement parking when a garage is converted to an ADU.

How long does Chino take to approve an ADU permit?

State law gives the city 60 days to decide a complete application. Chino's published plan check estimate is 4 to 5 weeks for the first review and 1 to 2 weeks for each recheck, and the fire district review takes 7 to 10 business days.

Want a timeline for your lot?

Call and tell us what you want to build and where. We will walk you through it.

Mon to Fri, 7 AM to 5 PM