1. What is an Accessory Dwelling Unit?
An ADU is an accessory or second dwelling unit, including its own kitchen, bedroom, and bathroom facilities, attached or detached from the primary dwelling unit on the zoning lot. ADUs are intended to be “accessory” to the main house, and are typically much smaller and sited to the rear or side of the house.
2. Why are ADUs important?
As identified in the Mayor’s Affordable Housing Strategy, there is a major shortage of affordable housing on Oahu, especially for rental housing. ADUs can help address this problem by allowing existing homeowners to build a second unit on their property. In addition, seniors will have the option to age in place by moving into the ADU and renting the larger home for additional income.
3. Where can I build an ADU?
An ADU can be built on any lot zoned Residential (R-3.5, R-5, R-7.5, R-10, and R-20) or Country District with a lot area of 3,500 square feet (SF) or more provided that there is adequate infrastructure and subject to meeting all other Land Use Ordinance provisions for the zoning lot and there are no restrictive covenants.
4. How big can an accessory dwelling unit be?
An ADU can be a maximum of 400 SF for lots ranging between 3,500 SF and 4,999 SF and 800 SF for lots greater than 5,000 SF.