California ADU rules · Los Angeles County
Can I Build an ADU in Manhattan Beach?
Yes — you can build an ADU in Manhattan Beach. California's statewide ADU law requires every city, including Manhattan Beach, 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 rule2 total (1 ADU + 1 JADU, or 2 ADUs but only 1 detached); if JADU present, only 1 ADU allowed
Only one detached ADU allowed per lot; if a JADU is present, only one ADU is allowed in addition.
Units on a multifamily lot
Local ruleNew multifamily: 1 ADU per lot; Redevelopment: up to 25% of pre-existing units as ADUs (rounded down), not more than number of pre-existing units
New multifamily limited to 1 ADU per lot; redevelopment follows state 25% rule.
Junior ADU (JADU)
Local ruleAllowed
JADUs allowed only on single-family lots.
Size & height
Max detached ADU size
Local rule1,200 sq ft
Studio/1-bed: 850 sq ft; 2+ beds: 1,200 sq ft. Local max matches state ceiling.
Max attached ADU size
Local rule50% of primary, not to exceed detached ADU maximums (850/1,200 sq ft)
Attached ADU max is 50% of SFR, capped at detached ADU max.
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 minimum is 220 sq ft; must be within existing/proposed SFR.
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
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
Local rule5 ft
Detached ADUs must be at least 5 ft from other buildings on the lot.
Parking
Parking required
Local ruleUp to 1 space
1 off-street space per ADU; JADUs require no additional parking.
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 if garage/carport is converted.
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 JADU (owner must occupy primary or JADU); not required 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
Local ruleADU permit (ministerial), Building permit
Both ADU permit and building permit required.
Manhattan Beach-specific factors that can change the answer
State law sets the floor, but these local conditions often decide whether a specific parcel works.
Sprinkler requirement if primary dwelling requires sprinklers
ADU must have sprinklers if primary dwelling does
Manhattan Beach allows only one detached ADU per lot and requires a 5-foot separation from other buildings. Detached ADUs above or below a garage may be up to 26 feet tall.
Frequently asked questions
Can I build an ADU in Manhattan Beach?
Yes. California's statewide ADU law requires Manhattan Beach 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 Manhattan Beach?
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 Manhattan Beach?
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 Manhattan Beach?
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 Manhattan Beach?
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 Manhattan Beach?
Owner-occupancy: only for a jadu. ADUs under 750 sq ft are also exempt from impact fees.
Sources
- MBMC Chapter 10.74; Ord. No. 21-0001 (eff. Feb. 19, 2021)
- MBMC § 10.74.040(A); § 10.74.030(F)
- MBMC § 10.74.050
- MBMC § 10.74.040(B)(1)
- MBMC § 10.74.040(B)(1)(a)
- MBMC § 10.74.050(1)
- MBMC § 10.74.040(B)(4)
- MBMC § 10.74.040(F); § 10.74.050(7)
- MBMC § 10.74.040(F)(4)
- MBMC § 10.74.050(6); § 10.74.030(D)(2)
- MBMC § 10.74.030(A), (D)(4)
- MBMC § 10.74.040(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 § 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)
- 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 Manhattan Beach'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 Manhattan Beach Planning before relying on it.
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