Chino Hills Zoning and ADU Guide for Homeowners and Sellers

Last updated November 13, 2026. Reviewed by the Cash Home Buyers CA team. Information comes from the City of Chino Hills; sources are listed at the end.

Chino Hills allows one ADU and one junior ADU (JADU) per property in single-family residential zones, with no owner-occupancy requirement. Detached ADUs top out at 850 sq ft for one bedroom or 1,000 sq ft for two or more, and a JADU is capped at 500 sq ft.

Chino Hills ADU rules at a glance

Detached ADUs need independent water, gas and electric lines with separate meters. The city page does not describe the application process, so call City Hall at 909-364-2600 or Community Development at 909-364-2740.

What if my Chino Hills ADU or garage conversion has no permit?

Ask Community Development what records exist for your address. The city lists unpermitted construction among its code enforcement issues, so see our Chino Hills code enforcement guide.

How an unpermitted unit affects a sale

Sellers generally have to disclose known unpermitted work. On a traditional sale, buyers may ask for the unit to be legalized, removed or priced out, and lenders can be cautious about living space missing from city records. A cash buyer can purchase the property with the unit unresolved and price the risk into the offer.

How to sell a house in Chino Hills with an unpermitted ADU

1. Check city records. See our Chino Hills building permits guide.
2. Ask Community Development. Find out what legalizing would take.
3. Compare options. Legalize, sell with a credit, or sell as-is.
4. Disclose honestly. A cash offer does not change what you must disclose.

See selling a house as-is in Chino Hills or our cash-offer process.

Questions about your unit? Call (424) 435-2326 or request a cash offer. No cost, no obligation.

Chino Hills ADU numbers, laid out for a seller

The city lists a minimum ADU size of 220 square feet, a detached maximum of 850 square feet for one bedroom or 1,000 square feet for two or more, and a JADU of up to 500 square feet. Height is 18 feet for a one-story unit.

The front setback matches the main house and side and rear setbacks are 4 feet, measured from the eave.

Parking is one off-street space for an ADU with one or more bedrooms, with exemptions such as being within a half mile of public transit or entirely within an existing home or garage. Owner occupancy is not required, and the minimum rental term is 31 days.

Utilities and fees buyers ask about

Detached ADUs need independent water, gas and electric lines with separate meters. Development Impact Fees apply to ADUs of 750 square feet or more, not to JADUs. If you are selling a unit, ask for proof that the meters and fee payments were handled, and note that the page itself does not describe the application process, so call City Hall at 909-364-2600 or Community Development at 909-364-2740.

The ADU Ineligibility District

The city’s page notes an exception to ADU eligibility called the ADU Ineligibility District, cited as CHMC 16.10.140(H). Before assuming your lot can hold a unit, or that a buyer can add one, ask Community Development whether the address falls inside it.

Chino Hills zoning and ADU FAQ

What is the minimum rental term for a Chino Hills ADU?

The city lists a minimum rental term of 31 days.

Does a Chino Hills ADU need its own utility meters?

The city says detached ADUs need independent water, gas and electric lines with separate meters.

How big can a Chino Hills ADU be?

Detached ADUs can be 850 sq ft with one bedroom or 1,000 sq ft with two or more. A JADU is limited to 500 sq ft.

Do I have to live on the property?

The city says no owner occupancy is required for ADUs or JADUs.

Is parking required for a Chino Hills ADU?

One off-street space for an ADU with one or more bedrooms, unless an exemption applies.

Can I sell a Chino Hills house with an unpermitted ADU?

Yes, with disclosure. A cash buyer can purchase it as-is and price the risk into the offer.

What the numbers mean for an owner

Chino Hills’ ADU standards are unusually specific, which helps when you check whether an existing unit fits the rules. A detached unit is limited to 850 square feet with one bedroom or 1,000 square feet with two or more, with a 220-square-foot minimum, and a one-story unit is capped at 18 feet tall.

Setbacks are 4 feet on the side and rear, measured from the eave, and the front setback matches the main house. A JADU is limited to 500 square feet. ADUs of 750 square feet or more are subject to Development Impact Fees; JADUs are not.

The city also requires independent water, gas and electric lines with separate meters for detached ADUs, which is a good first clue when you are trying to tell whether an older guest house was built to current standards. Check the ADU Ineligibility District in CHMC 16.10.140(H) to see whether your lot is excluded.

If you plan to rent or sell the unit

• The minimum rental term is 31 days.
• No owner occupancy is required.
• One off-street parking space is required for an ADU with a bedroom, with exemptions such as being within a half mile of public transit or entirely inside an existing home or garage.

Disclosing an ADU in Chino Hills

A buyer will ask whether the unit was permitted. Under Civil Code 1102.1, the transfer disclosure statement cannot be waived in an as-is sale, and a late disclosure lets the buyer cancel within three days of in-person delivery or five days of mailing. See our California as-is guide, the natural hazard disclosure guide and the Chino Hills building permits guide.

Sources

• City of Chino Hills: Accessory Dwelling Units

This guide is general information, not legal advice. Rules change; confirm requirements with the City of Chino Hills.