ADU addition rules in Hawaii (Oahu) and how to build a legal quad

[Caleb MacDonald]

Hi all.

I've been looking for potential house hacking properties on Oahu and have found several on the MLS that come with 4 separate units. It all cases 3 of the 4 units have a reduced kitchen meaning that either there is no stove (only a cooktop) or the refrigerator is in a different room. These properties all seem to have been modified to their current condition as quadplexes, but I've also read that only one or now maybe two ADUs are permitted per property.

Bottom line is that ADU limitation rules as I read them would not allow 4 units to exist on one residential property, so how is it that these properties have four units? I suspect that because they don't have "full" kitchens they can skirt the ADU rules.

I may be interested in buying a single family or duplex and adding more units to it to bring it up to four total units, but I would like to understand how the kitchen design would allow me to do this legally. Does anyone have knowledge on this?   

Thanks BP community!