Considering building an Accessory Dwelling Unit? Before you dive it, it’s important to understand the Department of Planning and Permitting Guidelines. Here are five major considerations to make as you take the appropriate steps toward building an Accessory Dwelling Unit (ADU).

1. Is there a difference between an ADU and Ohana housing? Yes, these terms are often used interchangeably, however, they are different. Ohana dwellings restrict occupancy to family members and have no size limitations. Ohana units come with their own specific set of guidelines and require two off-street parking spaces. ADUs, which do not require family living within them, requires only one off-street parking space and have size limitations.
2. What defines an ADU? An ADU is a second “home” that includes its own kitchen, bedroom, and bathroom that is either attached or detached from the primary dwelling unit on the zoning lot. These units are intended to be “accessories” to the main unit and are typically smaller in size.
3. Where can an ADU be built? An ADU can be constructed on Residentially or County zoned lot with an area of 3,500 square feet or more. The area must supply an adequate infrastructure and meet all other Land Use Ordinance provisions for the zoning. There must be no other restrictive covenants.
4. How big can I build my ADU? ADU can be no larger than 400 square feet for lots ranging between 3,500 and 4,999 square feet. Lots greater than 5,000 square feet can have units up to 800 square feet.
5. What are the different ways by which I can add an ADU to my lot? New units can be built separately from the main dwelling unit or attached. Existing structures, such as garages, basements or attics can be converted to ADU pending building code standards are met.

There are a number of other major considerations to make and we will continue to address these in future posts. These represent the very basics in terms of what you need to know so it is extremely important that you speak with a professional architect in order to fully understand everything from the permit acquisition process to who can reside within your ADU space.  If you have questions in the meantime, please fill out our online estimator for more information.