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UpsideADU

Rules & Permits · 2026

ADU rules & permits by county

California sets the ADU floor — 4 ft setbacks, units to 1,200 sq ft, a 60-day permit clock — but the office that reviews your build, and the local site conditions, change by county. Pick yours.

For the statewide picture — SB 1211, AB 1033, and the 2025 preemption — see California ADU law in 2026.

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