ADU Rules in Manhattan Beach.
Local ADU regulations, permit fees, setback requirements, and typical timelines for Manhattan Beach. Last updated 2026-05-27.
Manhattan Beach ADU Requirements
Attached ADU: up to 25 ft
Manhattan Beach has limited transit access; replacement parking is generally required for garage conversions.
Manhattan Beach assesses a separate school impact fee for new ADUs.
Design 5 weeks · Permit 7 weeks · Build 38 weeks
Plain-language summary
In Manhattan Beach, a detached ADU requires a minimum 4-foot side setback and 4-foot rear setback. The maximum height for a detached ADU is 16 feet, while an attached ADU may be up to 25 feet. The maximum size for a detached ADU is 1,200 sq ft; a Junior ADU (JADU) is limited to 500 sq ft. Replacement parking is required for most projects. Typical permit fees range from $10,000 to $20,000. A typical project takes approximately ~12 months from design start to move-in, including 5 weeks of design, 7 weeks for permit review, and 38 weeks of construction.
⚠️ ADU rules change frequently. Always verify current requirements with the Manhattan Beach Building & Safety Department before submitting plans. Official source →
What to Watch Out For
- Coastal Zone applies to properties within the coastal development overlay area (generally west of Sepulveda Blvd). CDP required.
- Manhattan Beach has smaller average lot sizes; confirm lot coverage limits before designing.
- Alley-loaded lots (common in the sand section) have specific ADU placement guidelines.
How Long Does It Take to Get an ADU Permit in Manhattan Beach?
Site study, floor plans, elevations, structural drawings.
Plan check, corrections, and permit issuance by Manhattan Beach Building & Safety.
Foundation, framing, MEP rough-in, finishes, final inspection.
A licensed engineer on your lot, free.
30 minutes. We walk the property, figure out what's feasible, and answer any questions you have.
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