California ADU rules · Orange County

Can I Build an ADU in Yorba Linda?

Yes — you can build an ADU in Yorba Linda. California's statewide ADU law requires every city, including Yorba Linda, to approve a qualifying accessory dwelling unit by right, plus a junior ADU (JADU) on a single-family lot. What varies city to city are the local specifics below.

Figures below reflect Yorba Linda's adopted ADU ordinance layered on California state law.

Can you build one?

ADUs allowed

Local rule

Conditional

Detached ADUs over 1,000 sq ft (up to 1,200 sq ft on lots ≥15,000 sq ft) require discretionary Design Review; otherwise, ADUs and JADUs are ministerial.

§ 18.20.830, § 18.20.850.D.2

Units on a single-family lot

CA state law

1 ADU + 1 JADU

At least one ADU and one JADU per single-family lot (a conversion ADU may also be possible).

Cal. Gov. Code § 66323 (by-right ADU/JADU, 800 sq ft, 4-ft setbacks)

Units on a multifamily lot

Local rule

conversions (>=1 or 25% of units) + up to 2 detached

Only up to 2 detached ADUs allowed per multifamily lot, not 4 or 8 as in state baseline.

§ 18.20.830.C, § 18.20.840.B

Junior ADU (JADU)

CA state law

Allowed

Up to 500 sq ft, within the walls of an existing single-family home (single-family lots only).

Cal. Gov. Code § 66333 (junior ADUs)

Size & height

Max detached ADU size

Local rule

1,000 sq ft

Ministerial max is 1,000 sq ft; up to 1,200 sq ft allowed with discretionary review on lots ≥15,000 sq ft.

§ 18.20.850.D.1–2

Max attached ADU size

Local rule

1,000 sqft or 50% of primary, whichever is greater (up to 1,200 sqft discretionary on lots ≥15,000 sqft)

Ministerial max is 1,000 sq ft or 50% of primary dwelling, whichever is greater; up to 1,200 sq ft with discretionary review on large lots.

§ 18.20.850.D.1–2

Guaranteed minimum size

CA state law

800 sq ft

An 800 sq ft ADU must be allowed regardless of FAR/lot-coverage caps; a city also cannot cap an attached ADU below 850 sq ft (1,000 for 2+ bedrooms).

Cal. Gov. Code § 66321 (size minimums & height)

Max JADU size

CA state law

500 sq ft

Cal. Gov. Code § 66333 (junior ADUs)

Max height

CA state law

16 ft

16 ft baseline; cities must allow 18 ft within ½ mi of a major transit stop or where the primary dwelling is two-story, and 20 ft on a lot with a multistory multifamily building.

Cal. Gov. Code § 66321 (size minimums & height)

Setbacks

Side setback

CA state law

4 ft

A city cannot require more than 4 ft side or rear setback; conversions of existing structures are exempt.

Cal. Gov. Code § 66323 (by-right ADU/JADU, 800 sq ft, 4-ft setbacks)

Rear setback

CA state law

4 ft

Cal. Gov. Code § 66323 (by-right ADU/JADU, 800 sq ft, 4-ft setbacks)

Front setback

Local rule

must meet front yard setback of zoning district

Front setback must comply with base zone; no local override to allow encroachment.

§ 18.20.850.F

Separation from main house

Local rule

None required

No specific separation required; must comply with building/fire code.

§ 18.20.850.C

Parking

Parking required

Local rule

Up to 1 space

1 space per ADU required unless exempt; no parking required for JADUs.

§ 18.20.850.E, § 18.20.860.F

Transit parking exemption

CA state law

Yes — no parking required near transit & for conversions

No parking may be required within ½ mi walking distance of transit, in a historic district, for an ADU within an existing structure, within one block of car-share, or in certain permit-parking areas.

Cal. Gov. Code § 66322 (ADU parking; § 66334 covers JADU parking)

Garage-conversion replacement parking

Local rule

Not required

No replacement parking required for garage/carport conversions.

§ 18.20.850.E

Approval, timeline & cost

Approval path

CA state law

Ministerial (by right)

No public hearing or discretionary design review for a qualifying ADU.

Cal. Gov. Code § 66317 (ministerial approval, 60-day deadline)

Approval timeline

CA state law

60 days

The agency must act within 60 days of a complete application — and the ADU is deemed approved if it does not.

Cal. Gov. Code § 66317 (ministerial approval, 60-day deadline)

Owner-occupancy

Local rule

Only for a JADU

Owner-occupancy required for JADUs; not required for ADUs permitted 2020–2025 per state override.

§ 18.20.850.H, § 18.20.860.B

Impact-fee waiver

CA state law

Waived under 750 sq ft

An ADU of 750 sq ft or less pays no impact fees (the 750 sq ft threshold itself is exempt under § 66311.5); larger ADUs pay fees proportional to the primary dwelling. JADUs (≤ 500 sq ft) are exempt.

Cal. Gov. Code § 66311.5 (impact fees: none for an ADU ≤ 750 sq ft or JADU ≤ 500 sq ft)

Permits required

CA state law

Building permit

Only a ministerial building permit — no conditional use permit or discretionary design review for a qualifying ADU.

Cal. Gov. Code § 66317 (ministerial approval, 60-day deadline)

Yorba Linda-specific factors that can change the answer

State law sets the floor, but these local conditions often decide whether a specific parcel works.

Very High Fire Hazard Severity Zone (VHFHSZ)

ADUs must comply with local fire/building code; no special ADU prohibition.

Historic District

ADUs in historic districts are exempt from parking requirements.

Yorba Linda caps ministerial detached ADUs at 1,000 sq ft (up to 1,200 sq ft with discretionary review on large lots) and allows only 2 detached ADUs on multifamily lots. Attached ADUs may be larger than 1,000 sq ft if they do not exceed 50% of the primary dwelling, subject to the same discretionary review for larger units.

Frequently asked questions

Can I build an ADU in Yorba Linda?

Yes. California's statewide ADU law requires Yorba Linda to approve a qualifying accessory dwelling unit ministerial (by right), plus a junior ADU (JADU) on a single-family lot.

How big can an ADU be in Yorba Linda?

A detached ADU of at least 1,000 sq ft must be allowed, and an ADU of 800 sq ft can never be zoned out by floor-area or lot-coverage limits. A JADU can be up to 500 sq ft.

What are the setback requirements for an ADU in Yorba Linda?

Side and rear setbacks are limited to 4 ft. must meet front yard setback of zoning district.

Is parking required for an ADU in Yorba Linda?

Up to 1 space. No parking can be required within ½ mile of transit, for conversions, or for units inside the primary home. When a garage is converted, replacement parking is not required.

How long does ADU approval take in Yorba Linda?

A complete application must be acted on within 60 days, with ministerial (by right) — no public hearing or discretionary design review for a qualifying ADU.

Do I have to live on the property to build an ADU in Yorba Linda?

Owner-occupancy: only for a jadu. ADUs under 750 sq ft are also exempt from impact fees.

Sources

  • Yorba Linda Municipal Code, Article 9, Sections 18.20.800–18.20.870 (Ord. 2023-1106)
  • § 18.20.830, § 18.20.850.D.2
  • § 18.20.830.C, § 18.20.840.B
  • § 18.20.850.D.1–2
  • § 18.20.850.F
  • § 18.20.850.C
  • § 18.20.850.E, § 18.20.860.F
  • § 18.20.850.E
  • § 18.20.850.H, § 18.20.860.B
  • Cal. Gov. Code §§ 66310–66342 (ADU Law)
  • HCD 2025 Accessory Dwelling Unit Handbook
  • Cal. Gov. Code § 66323 (by-right ADU/JADU, 800 sq ft, 4-ft setbacks)
  • Cal. Gov. Code § 66333 (junior ADUs)
  • Cal. Gov. Code § 66321 (size minimums & height)
  • Cal. Gov. Code § 66322 (ADU parking; § 66334 covers JADU parking)
  • Cal. Gov. Code § 66317 (ministerial approval, 60-day deadline)
  • Cal. Gov. Code § 66311.5 (impact fees: none for an ADU ≤ 750 sq ft or JADU ≤ 500 sq ft)

Last updated 2026-06-25. This is an AI-assisted summary of Yorba Linda's ADU rules, drawn from its published ordinance and California ADU law — general information, not legal advice, and it may be incomplete or out of date. Verify the controlling rule for your specific parcel with Yorba Linda Planning before relying on it.

Will an ADU work on your Yorba Linda lot?

Ask GoCodebook about your address and get the size, setback, parking and permit rules that actually apply to your parcel — with the exact citation.

Check my parcel free

Related