Kauai County, HI Building Setbacks & Zoning: Setback Rules (2026)

Section 8-4.3(b) of the Kaua'i County Code 1987 sets the baseline yard setbacks for every Residential District structure not involving a land subdivision. The front setback bars any structure, including garages, carports, decks above grade, and accessory or storage structures, from coming closer than 10 feet to the right-of-way line of a public thoroughfare, a private street's property line, or the pavement line of a driveway or parking lot serving more than three dwelling units. The rear setback is 5 feet or half the total height of the nearest building wall, whichever is greater, and the side setback follows the same five-feet-or-half-wall-height formula measured from the ground to the highest wall nearest the property line.

Section 8-4.3(b)(4) further limits how far eaves, roof overhangs, and other appurtenances may project into a required setback, capping the intrusion at half the setback distance or four feet, whichever is less, while fences under six feet are exempt. Section 8-4.3(b)(7) lets the Planning Department impose a larger setback than these minimums as a permit condition where topography, drainage, sun exposure, or privacy concerns warrant it. For subdivided parcels, § 8-4.4(a)(4) applies the same § 8-4.3(b) figures but allows an applicant to vary front setbacks on the subdivision map as long as none is under 10 feet, and § 8-4.4(b)(4) sets a 15-foot rear setback (25 feet where a maintenance easement is required) for single-family attached lots. Multi-family lots use the § 8-4.3(b) figures too, under § 8-4.4(c)(4).