ADU rules in Urban Honolulu, HI — also called accessory dwelling unit regulations or granny flat ordinances — cover setbacks, owner-occupancy, parking, and permit requirements.
Most Urban Honolulu lots sit in apartment or mixed-use zones where ADUs under ROH Sec. 21-5.720 are not permitted; ADUs are generally limited to R-5 through R-20 single-family neighborhoods like Manoa, Kaimuki, and Nuuanu.
Because Urban Honolulu is dominated by A-1, A-2, BMX, and commercial districts that already allow multiple dwelling units, the accessory dwelling unit framework in ROH Sec. 21-5.720 rarely applies. ADUs are permitted only in Country, R-3.5, R-5, R-7.5, R-10, and R-20 districts, which in the Urban Honolulu CDP cover neighborhoods such as Manoa, Makiki Heights, Kaimuki, Nuuanu, and Kalihi Valley. Lots in these zones must meet minimum lot size, parking, and owner-occupancy rules. Ordinance 25-2 (2025) refined permit and advertising provisions. After-the-fact permits are available for pre-September 14, 2015 units. ADUs may not be rented for less than 30 days.
Building an ADU on an apartment-zoned Urban Honolulu lot, short-term rental below 30 days, or advertising an unpermitted unit can trigger notices of violation and daily civil fines.
Urban Honolulu, HI
ROH 15-14.5 drives Schedule XXII no-parking signs throughout Urban Honolulu, while ROH 15-13.5 sets how close to the curb vehicles must park.
Urban Honolulu, HI
LUO 21-6.60 requires EV-ready stalls in new multi-family (8+ stalls) and commercial (12+ stalls) parking across Urban Honolulu, with compact resizing allowed...
Urban Honolulu, HI
ROH 15-16.6 prohibits storage parking of commercial vehicles on Urban Honolulu streets without posted signs; LUO 21-6.20 sets the companion off-street parkin...
Urban Honolulu, HI
Urban Honolulu has no blanket overnight parking ban; ROH 15-14.6 enforces parking prohibited during certain hours only on sign-posted routes.
Urban Honolulu, HI
ROH 15-14.1 prohibits stopping, standing, or parking in front of any public or private driveway or within 4 feet of either side across dense Urban Honolulu n...
Urban Honolulu, HI
Urban Honolulu property owners obtain fence and wall permits from the Honolulu Department of Planning and Permitting under ROH 18-3.1, which exempts retainin...
Side-by-side rule comparisons with other cities in Honolulu County.
See how other cities in Honolulu County handle adu rules.
See how Urban Honolulu's adu rules rules stack up against other locations.
Help us keep this page accurate. If you notice an error or outdated information, let us know.