California ADU rules · Riverside County
Can I Build an ADU in Norco?
Yes — you can build an ADU in Norco. California's statewide ADU law requires every city, including Norco, 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.
Can you build one?
ADUs allowed
CA state lawYes — by right
ADUs and JADUs are allowed by right in all residential and mixed-use zones; ministerial approval, no hearing.
Units on a single-family lot
CA state law1 ADU + 1 JADU
At least one ADU and one JADU per single-family lot (a conversion ADU may also be possible).
Units on a multifamily lot
Local ruleconversions (>=1 or 25% of units) + up to 2 detached
Norco limits detached ADUs on multifamily lots to 2, not 8.
Junior ADU (JADU)
CA state lawAllowed
Up to 500 sq ft, within the walls of an existing single-family home (single-family lots only).
Size & height
Max detached ADU size
Local rule1,200 sq ft
Local cap is 1,200 sq ft, including up to 50 sq ft each of patio/porch.
Max attached ADU size
Local rule850 (studio/1-bed), 1,000 (2-bed); conversions: no limit but ≤50% of primary
Explicit local size caps for attached ADUs; conversions limited by 50% of primary.
Guaranteed minimum size
CA state law800 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).
Max JADU size
CA state law500 sq ft
Max height
CA state law16 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.
Setbacks
Side setback
CA state law4 ft
A city cannot require more than 4 ft side or rear setback; conversions of existing structures are exempt.
Rear setback
CA state law4 ft
Front setback
Local ruleADUs not allowed in front yard setback, except as needed to enable 800 sq ft ADU with 4 ft setbacks
Front setback exception only to guarantee state-minimum ADU.
Separation from main house
Local rule10 ft
Detached ADUs must be at least 10 ft from all other buildings.
Parking
Parking required
CA state lawUp to 1 space
At most 1 space per ADU (or per bedroom, whichever is less) — and waived in the common cases below.
Transit parking exemption
CA state lawYes — 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.
Garage-conversion replacement parking
CA state lawNot required
When a garage/carport is demolished or converted to build an ADU, replacement parking cannot be required.
Approval, timeline & cost
Approval path
CA state lawMinisterial (by right)
No public hearing or discretionary design review for a qualifying ADU.
Approval timeline
CA state law60 days
The agency must act within 60 days of a complete application — and the ADU is deemed approved if it does not.
Owner-occupancy
Local ruleOnly for a JADU
Owner occupancy required for JADUs only.
Impact-fee waiver
CA state lawWaived 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.
Permits required
CA state lawBuilding permit
Only a ministerial building permit — no conditional use permit or discretionary design review for a qualifying ADU.
Norco-specific factors that can change the answer
State law sets the floor, but these local conditions often decide whether a specific parcel works.
Historic District Demolition Notice
Special demolition notice required for ADUs in historic districts.
Animal Area Preservation
ADU location must preserve required animal keeping area (PAKA) or open animal area per animal units.
Norco limits detached ADUs on multifamily lots to 2 and requires a 10-foot separation from all other buildings for detached ADUs. Unique local rules require ADUs to preserve animal keeping areas.
Frequently asked questions
Can I build an ADU in Norco?
Yes. California's statewide ADU law requires Norco 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 Norco?
A detached ADU of at least 1,200 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 Norco?
Side and rear setbacks are limited to 4 ft. ADUs not allowed in front yard setback, except as needed to enable 800 sq ft ADU with 4 ft setbacks.
Is parking required for an ADU in Norco?
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 Norco?
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 Norco?
Owner-occupancy: only for a jadu. ADUs under 750 sq ft are also exempt from impact fees.
Sources
- Norco Municipal Code § 18.30.47, Ord. 1111 (2024), Ord. 1117 (2024)
- Norco Municipal Code § 18.30.47(E)(5)
- Norco Municipal Code § 18.30.47(E)(1)(b)
- Norco Municipal Code § 18.30.47(E)(1)(a)
- Norco Municipal Code § 18.30.47(E)(2)(e)
- Norco Municipal Code § 18.30.47(E)(2)(c)
- Norco Municipal Code § 18.30.47(F)(3)
- Norco Municipal Code § 18.30.47(E)(19)
- Norco Municipal Code § 18.30.47(E)(7)
- Cal. Gov. Code §§ 66310–66342 (ADU Law)
- HCD 2025 Accessory Dwelling Unit Handbook
- Cal. Gov. Code § 66317 (ministerial approval, 60-day deadline)
- 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 § 66314 (local ordinance standards)
- 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 Norco'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 Norco Planning before relying on it.
Will an ADU work on your Norco 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