California ADU rules · Los Angeles County
Can I Build an ADU in Bell?
Yes — you can build an ADU in Bell. California's statewide ADU law requires every city, including Bell, 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 ruleup to 2 detached OR conversions (>=1 or 25% of units, rounded down)
Bell limits detached ADUs on multifamily lots to 2, not 4 or 8 as in state law.
Junior ADU (JADU)
Local ruleAllowed
JADUs allowed only within or attached to a single-family dwelling, not in detached garages.
Size & height
Max detached ADU size
CA state law1,200 sq ft
Statewide default cap for detached new-construction ADUs in the absence of a compliant local ADU ordinance. The unconditional by-right floor a city must always allow is 800 sq ft (see Guaranteed minimum size); a city with a compliant ordinance may set its own ceiling.
Max attached ADU size
Local rule50% of primary or 1,200 sq ft, whichever is less (>=800 if otherwise precluded)
Same rule as detached; must allow at least 800 sq ft if otherwise precluded.
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
Local rule500 sq ft
JADU max size is 500 sq ft or 50% of primary dwelling, whichever is less.
Max height
Local rule16 ft
Detached ADUs limited to 1 story, 16 ft; above-garage ADUs allowed in R-2, R-3, C-3R zones.
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 rulesame as main building
Front setback for ADUs matches main building; conversions exempt.
Separation from main house
Local rule10 ft
Detached ADUs must be at least 10 feet from the primary dwelling.
Parking
Parking required
Local ruleUp to 1 space
1 space per ADU or per bedroom (whichever is less); exemptions per state law.
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 garage/carport is converted or demolished for ADU.
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, not for ADUs.
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.
Bell-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
ADUs in historic districts are exempt from parking requirements.
Bell limits detached ADUs on multifamily lots to 2 and requires a 10-foot separation from the primary dwelling for detached ADUs. ADU and JADU sizes are capped at 50% of the primary dwelling or 1,200 sq ft, whichever is less.
Frequently asked questions
Can I build an ADU in Bell?
Yes. California's statewide ADU law requires Bell 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 Bell?
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 Bell?
Side and rear setbacks are limited to 4 ft. same as main building.
Is parking required for an ADU in Bell?
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 Bell?
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 Bell?
Owner-occupancy: only for a jadu. ADUs under 750 sq ft are also exempt from impact fees.
Sources
- Bell Municipal Code Chapter 17.54 (Ord. 1266 § 9, 2020)
- § 17.54.050(B)
- § 17.54.020, Table 17.54.050-1
- Table 17.54.050-1, § 17.54.050(E)(5)
- Table 17.54.050-1
- Table 17.54.050-1, § 17.54.050(E)(2)
- § 17.54.050(E)(4)
- § 17.54.070
- § 17.54.070(E)
- § 17.54.100
- 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 § 66321 (size minimums & height)
- Cal. Gov. Code § 66322 (ADU parking; § 66334 covers JADU parking)
- 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 Bell'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 Bell Planning before relying on it.
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