Kauai County has 3 different zoning designations for accessory type of dwelling units on residential properties. Here we cover the differences of these designations.

ARU (Additional Rental Unit)

• 1 ARU allowed per main dwelling
• 800 sf max
• 1 additional parking space (In addition to the normal 2 parking spaces for a main dwelling)
• Must have a kitchen
• No short term rentals (6 month min.)
• May be attached or detached
• May be eligible for Additional Rental Unit (ARU) Subsidy

ARU zoning code defintion: Means a rental unit that includes a kitchen, bedroom(s) and bathroom facilities, attached or detached from a dwelling unit that is used for the purpose of a long term rental unit. When built within an existing residential dwelling unit or attached to one, the two units together shall constitute a multi-family dwelling. An additional rental unit is not a dwelling unit.

Guest House

• 1 Guest House allowed per main dwelling
• May be attached or detached
• 800 sf max
• 1 additional parking space (In addition to the normal 2 parking spaces for a main dwelling)
• Does not necessarily need a kitchen
• Not be able to be combined with ARU (Says you can have 1 ARU or 1 guest house, but not both)
• Can be for tenant, guest, or owner use
• No short term rentals (6 month min. )

Guest House zoning code definition: Means a building with a floor area of no more than 800 square feet, may contain a kitchen, and is used for dwelling purposes by guests, tenants, or owner(s). A Guest House shall not be used for a transient vacation rental (TVR) or homestay operation within or outside of the visitor destination area (VDA).

ADU (Additional Dwelling Unit)

• 1 ADU allowed per main dwelling
• May be attached or detached
• No square footage restriction (other square footage limitations may apply)
• 2 additional parking spaces required (In addition to the normal 2 parking spaces for a main dwelling)
• Must contain a kitchen
• May possibly be used for short term rentals (other restrictions apply)

ADU zoning code definition: Means a structure or portion thereof designed and used for single-family residential purposes as permitted under Article 15 of this Chapter, and which can be detached from or attached to an existing residence, to be used for single-family occupancy and containing one kitchen.

For all 3 types of accessory units in Kauai, you must first get sign offs from several outside departments, including:

• Department of water to make sure there is sufficient water,
• Sewer or septic (health dept)can handle the added bedroom(s)
• Fire Department

This is done via the “clearance forms” found on the county website.

Navigating the county requirements can be puzzling. Dalkita can help with this and help design your dream home expansion!

-Article by: Matthew Taylor-Rennert