Whittier Zoning and ADU Guide for Homeowners and Sellers

Last updated November 13, 2026. Reviewed by the Cash Home Buyers CA team. Information comes from City of Whittier planning and ADU pages; sources are listed at the end.

Whittier offers preapproved ADU plans and an ADU/JADU application through Planning Services. Check current requirements with the city before you build, legalize or sell a unit.

Whittier ADU resources at a glance

Does Whittier have preapproved ADU plans?

Yes. The city says its preapproved plans are currently for one-story, detached structures and lists several floor plans, from a 311 sq ft studio to larger layouts. A preapproved plan can shorten review, but you still need to apply to the city.

Can I rent an ADU on a short-term basis in Whittier?

No. The city’s short-term rental page says ADUs and JADUs are prohibited from receiving short-term rental permits, as are properties in zones that do not allow residential uses and those in high or very high fire severity zones. A buyer planning Airbnb-style income should know this.

How an ADU or garage conversion affects selling a house in Whittier

A permitted ADU can be a selling point. An unpermitted one is a problem lenders and inspectors notice. In California, sellers generally must disclose known unpermitted work. On a traditional listing you can try to permit the unit, remove it, price it in, or offer a credit.

How to sell a Whittier house with an unpermitted ADU

1. Check the city’s records for what is permitted at the address.
2. Gather what you have: plans, receipts, inspection cards.
3. Compare options: legalize, remove, or sell as-is.
4. Disclose honestly. A cash offer does not change disclosure duties but removes repair steps.

We buy Whittier houses as they are. See selling as-is in Whittier, our Whittier building permits guide and code enforcement guide.

Questions about a unit on your property? Call (424) 435-2326 or request a cash offer. There is no cost and no obligation.

Whittier’s preapproved ADU plans: sizes, styles and limits

Under Assembly Bill 1332, Whittier offers preapproved plans for one-story, detached ADUs in Craftsman, Spanish and Traditional styles. The city lists four plan sets: a 311-square-foot studio; a one-bedroom, one-bath unit at 495 square feet; a two-bedroom, one-bath unit at 757 square feet; and a two-bedroom, two-bath unit at 800 square feet.

The city notes that the preapproved plans cannot be modified in any way, so a lot that needs a different footprint would go through regular plan review instead.

Is your lot eligible for a preapproved plan?

The city’s checklist says the property must be zoned for single-family residential use, such as R-E, H-R or R-1, with an existing or proposed single-family home.

Setbacks are specific: the ADU must keep at least 4 feet from the side and rear property lines, exterior walls with doors or windows need at least 5 feet, and there must be at least 5 feet between the ADU and any other structure, measured wall to wall.

Mechanical equipment such as an air conditioner condenser or heat pump must be at least 5 feet from the property line and screened from the public right of way.

How the Whittier preapproved ADU process works

1. Confirm your lot meets the criteria above.
2. Complete the pre-submittal requirements. The city lists a residential fire flow test and a sewer lateral inspection, both requested through the Online Permit Portal under the Engineering tab.
3. Prepare documents. The checklist includes the preapproved plans, a Title 24 building energy analysis report, a site map, a hold harmless agreement, site photographs of all sides of the property at least 4 by 6 inches, and a title report.
4. Apply online and pay. Create an account on the Online Permit Portal, choose the building permit record type and the Preapproved Accessory Dwelling Unit option, and upload the documents. Plan review and new address fees are invoiced after completeness review, and all fees must be paid before the permit is issued.
5. Plan review. The city says completeness review takes 1 to 2 business days, plan check about 5 business days, and resubmittals about 5 days.
6. Inspections and final. Inspections are scheduled on the portal under Section 109 of the 2022 California Residential Code, and the permit is finaled after the Planning Division and Building and Safety Division complete their final inspections.

The city adds that other plans, fees or permits may be needed, such as a solar photovoltaic system, a fire sprinkler system or a geotechnical report.

What state law guarantees ADU owners

State law sets floors that cities cannot undercut, and the Department of Housing and Community Development’s March 2026 ADU Handbook summarizes them.

Local agencies must act on a complete application within 60 days, must allow ADUs of at least 800 square feet, and cannot require more than 4 feet of side and rear setback. A detached ADU can be 16 feet high, or 18 feet near major transit with extra height for roof pitch.

ADUs of 750 square feet or less and JADUs of 500 square feet or less are exempt from impact fees charged by local agencies, special districts and water corporations.

Parking cannot exceed one space per unit or bedroom, and none can be required in listed cases such as within half a mile walking distance of transit or when the ADU is within the existing home. Rental terms must exceed 30 days.

Whittier’s own page layers local standards, such as the 5-foot separation, on top of these rules.

Short-term rentals and ADUs in Whittier

The city’s short-term rental page says ADUs and junior ADUs, properties in zones that do not allow residential uses, and properties in high or very high fire severity zones cannot receive STR permits.

Where STRs are permitted, the city requires applying through its RentalScape portal, getting a business license after approval, and posting the permit number on every listing. If you are buying or selling a house based on nightly-rental income from a backyard unit, this matters.

Selling a Whittier house with an unpermitted unit

An unpermitted garage conversion or backyard unit raises the same questions every time: does it meet the setbacks, egress and utility requirements, and was it ever inspected?

California Civil Code section 1102.1 keeps your duty to disclose material facts in place in an as-is sale, so a known unpermitted unit is disclosed.

Under section 1102.3, a disclosure that reaches the buyer after an offer lets the buyer cancel within three days of in-person delivery or five days of mailing or agreed electronic delivery.

Your choices are to legalize the unit, remove it, price the house accordingly, or sell to a cash buyer who takes it as is. See the Whittier building permits guide for how the city handles permit records.

Whittier zoning and ADU FAQ

Does Whittier have preapproved ADU plans?

Yes, for one-story, detached ADUs, including a 311 sq ft studio and a 495 sq ft one-bedroom, one-bath.

Can a Whittier ADU be a short-term rental?

No. The city says ADUs and JADUs are prohibited from receiving short-term rental permits.

Can I sell a Whittier house with an unpermitted ADU?

Yes. It must be disclosed, but a cash buyer can purchase the property as it is.

What sizes are Whittier’s preapproved ADU plans?

The city lists a 311 sq ft studio, a 495 sq ft one-bedroom with one bath, a 757 sq ft two-bedroom with one bath, and an 800 sq ft two-bedroom with two baths, all one-story and detached.

How long does Whittier take to review a preapproved ADU application?

The city says completeness review takes 1 to 2 business days, plan check about 5 business days and resubmittals about 5 days.

Can Whittier’s preapproved ADU plans be changed?

No. The city says the preapproved plans cannot be modified in any way.

Sources

• City of Whittier: Preapproved ADU Plans
• City of Whittier: Planning Services
• City of Whittier: Short-Term Rentals

This guide is general information, not legal advice. Zoning rules change; confirm with the City of Whittier.