ADU rules in Hawaii County, HI — also called accessory dwelling unit regulations or granny flat ordinances — cover setbacks, owner-occupancy, parking, and permit requirements.
Hawai'i County allows one ohana dwelling (accessory dwelling unit) on RS, RA, FA and A zoned lots. The lot must be a legal lot of record, meet height, yard and parking rules, and have adequate sewage, water, fire and street access.
Under HCC Chapter 25 (Zoning), Section 25-6-30, an ohana dwelling is permitted on building sites in the RS, RA, FA and A districts. Section 25-6-33 allows not more than one ohana unit per lot with the first single-family dwelling. Combined lot area must be at least 10,000 sq ft (25-6-35(a)), and the detached ohana unit's yards must equal the district minimums plus 5 extra feet. Ohana units are prohibited in the State conservation district and on lots already permitting multiple dwellings (25-6-32). No variances are allowed (25-6-38). 2024's Bill 123 renamed ohana units as 'accessory dwelling units' and eased limits.
Illegally constructed ohana dwellings are subject to enforcement, permit revocation and code-compliance action by the planning director (HCC 25-6-39.5, 25-6-39.6).
Other ordinances people look up for this city. Green dot = verified primary-source excerpt.
Hawaii County, HI
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Hawaii County, HI
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Hawaii County, HI
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See how Hawaii County's adu rules rules stack up against other locations.
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