California ADU rules · Los Angeles County
Can I Build an ADU in San Fernando?
Yes — you can build an ADU in San Fernando. California's statewide ADU law requires every city, including San Fernando, 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
Local rule1 detached ADU + 1 conversion ADU + 1 JADU
Allows both a detached and a conversion ADU plus a JADU on a single-family lot.
Units on a multifamily lot
Local ruleUp to 25% of existing units as ADUs (minimum 1); up to 2 detached ADUs (proposed multifamily); up to 8 detached ADUs (existing multifamily), not to exceed number of existing units
Detached ADU cap for existing multifamily is the lesser of 8 or the number of existing units.
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
1,200 sq ft for 2+ bedrooms; 850 sq ft for 1-bedroom detached ADUs.
Max attached ADU size
Local rule850 sq ft (1-bedroom) or 1,200 sq ft (2+ bedrooms), or 50% of primary dwelling’s gross floor area, whichever is less (but not less than 800 sq ft)
Local cap applies; not less than 800 sq ft.
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
Local rule18 ft
Detached ADU: 18 ft plus 2 ft for roof pitch; attached ADU: up to 25 ft or primary dwelling height limit.
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
CA state lawNo front setback may block the mandatory 800 sq ft / 16-ft / 4-ft-setback ADU; otherwise per base zone
Separation from main house
CA state lawNone required
No statewide separation requirement between the ADU and the primary dwelling.
Parking
Parking required
Local ruleNone
No parking required for ADUs or JADUs.
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
Local ruleNot required
No replacement parking required when converting a garage/carport.
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 only for JADUs.
Impact-fee waiver
Local ruleWaived under 750 sq ft
Impact fees waived for ADUs under 750 sq ft; school fees apply for ADUs 500+ sq ft.
Permits required
CA state lawBuilding permit
Only a ministerial building permit — no conditional use permit or discretionary design review for a qualifying ADU.
San Fernando allows both a detached and a conversion ADU plus a JADU on single-family lots, sets a local detached ADU max of 1,200 sq ft (2+ bedrooms), and requires no parking for ADUs or JADUs. Owner-occupancy is required only for JADUs.
Frequently asked questions
Can I build an ADU in San Fernando?
Yes. California's statewide ADU law requires San Fernando 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 San Fernando?
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 San Fernando?
Side and rear setbacks are limited to 4 ft. No front setback may block the mandatory 800 sq ft / 16-ft / 4-ft-setback ADU; otherwise per base zone.
Is parking required for an ADU in San Fernando?
None. 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 San Fernando?
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 San Fernando?
Owner-occupancy: only for a jadu. ADUs under 750 sq ft are also exempt from impact fees.
Sources
- San Fernando Municipal Code, Article IV, Division 1, Sec. 106-520 et seq. (Ord. No. 1732, 5-5-2025)
- Sec. 106-520(6), (13)
- Sec. 106-520(3)(b)
- Sec. 106-520(3)(a)
- Sec. 106-520(6)(4), (9)(3)
- Sec. 106-520(9), (13)(d)
- Sec. 106-520(11)(c)
- Sec. 106-520(15)(b), (13)(f)
- Sec. 106-520(15)(d)-(e)
- 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 § 66333 (junior ADUs)
- Cal. Gov. Code § 66321 (size minimums & height)
- Cal. Gov. Code § 66323 (by-right ADU/JADU, 800 sq ft, 4-ft setbacks)
- Cal. Gov. Code § 66322 (ADU parking; § 66334 covers JADU parking)
Last updated 2026-06-25. This is an AI-assisted summary of San Fernando'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 San Fernando Planning before relying on it.
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