1 rule for unincorporated Hawaii County, Hawaii.
Verified from official government sources
Hawaii County (the Big Island) regulates Accessory Dwelling Units, formerly called 'ohana dwellings,' under Chapter 25 (Zoning) of the Hawaii County Code. After the County Council passed Bill 123 in September 2024 (signed by Mayor Mitch Roth), the County abolished the separate ohana-permit process, redefined ohana units as 'Accessory Dwelling Units' (ADUs), and now allows up to three ADUs per lot in the RS (Single-Family Residential), RD (Duplex Residential), RA (Residential-Agricultural), A (Agricultural), and FA (Family Agricultural) zoning districts. Each ADU is capped at 1,250 sq ft of living area (lanais, garages and carports excluded), must meet the underlying zone's yard setbacks, must have potable water and an approved wastewater system, and is built under a regular building permit (no separate ADU permit required). Bill 123 was adopted to comply with HRS Sec. 46-4.8 (added by Act 39, SLH 2024), the state law that requires every Hawaii county to allow at least two ADUs on residentially-zoned urban lots.
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