Hawaii County, HI Building Setbacks & Zoning: Structure Height Limits (2026)

Hawaii County Code § 25-5-4 sets the RS (single-family residential) district height limit at thirty-five feet, measured under the general rules in § 25-4-20: no building or structure erected after 1996 may exceed the zoning district's established height limit, and any existing structure that already exceeds it can't be built any higher. Basements and other floors below ground don't count toward the limit at all; § 25-4-21 permits any number of underground floors in every district. Section 25-4-22 carves out a short list of exemptions, each capped separately: chimneys, spires, belfries, water tanks, monuments, steeples, antennae, flagpoles, vent pipes, fans and elevator-machinery screening may rise up to ten feet above the governing height limit; safety railings up to forty-two inches above it; utility poles, lines and telecommunication antennas up to five hundred feet from grade; one amateur radio antenna per building site up to ninety feet above grade; energy-saving devices like heat pumps and solar collectors up to eight feet above the limit; and, in the A and IA agricultural districts, nonresidential agricultural structures up to one hundred feet where the director finds the extra height above forty-five feet necessary.

Accessory structures are separately capped at twenty feet under § 25-4-23, regardless of the main district height limit, unless another section of the chapter says otherwise. A homeowner who can't meet the RS district's thirty-five-foot limit, minimum lot size or yard requirements isn't simply out of luck: § 25-5-8(e) lets the planning commission grant exceptions to RS height, building site area, average width and yard rules inside an approved planned unit development, and lets the director grant the same exceptions inside a cluster plan development.