Op-Ed: Proposed ADU rules could help boost Maui County housing supply
Op-Ed: Proposed ADU rules could help boost Maui County housing supply
By: Jonathan Helton | Grassroot Institute of Hawaiʻi
Helton is a policy analyst at the Grassroot Institute of Hawaiʻi and the author of the policy brief “Four more ways to speed up Lahaina’s wildfire recovery.”
“Maui County homeowners could soon have more freedom to build accessory dwellings on their properties if two recent proposals become law.
One, Bill 27 (2026), would authorize ADUs to be slightly larger than what is currently allowed. The measure is now awaiting Mayor Richard Bissen’s signature after the Maui County Council approved it on Friday, March 20.
The other, a proposed bill being reviewed by the various county planning commissions, would allow two ADUs on all residential lots throughout the county.
Sometimes referred to as ohana units or granny flats, ADUs have long been legal in Maui County. Between 2012 and 2024, more than 500 ADUs were permitted, equivalent to 6% of all units permitted during that time.
ARTICLE CONTINUES BELOW ADNow, these proposed changes would make it even easier for homeowners to build more ADUs, whether that be to facilitate more multigenerational family living or increase the supply of rental housing.
Specifically, Bill 27 would allow ADUs to be up to 720 square feet if built on lots smaller than a half-acre. Currently, ADUs on Maui cannot be larger than 500 square feet on lots that are smaller than 7,500 square feet, and must be no larger than 600 square feet on lots that are between 7,500 and 9,999 square feet.
Having an additional 120 to 220 square feet to work with would allow homeowners to add an extra bedroom or two or more living space in general.
As for allowing two ADUs on all residential lots throughout the county, this would obviously help ease the county’s housing shortage.
ARTICLE CONTINUES BELOW ADCurrently, homeowners in residential zones on Maui can construct two ADUs only on lots that are larger than 7,500 square feet, while for homeowners on Lānaʻi and Molokaʻi, 7,500 square feet is the threshold before they can even have one.
On Lānaʻi, where almost 75% of residential lots are smaller than 7,500 square feet, 1 this limitation makes ADUs functionally illegal. On Molokai, the majority of lots are 10,000 square feet or larger, but homeowners there are allowed only one ADU.
Allowing homeowners on all three islands to have at least two ADUs per residential lot would not only be a matter of fairness, it would also put the county in compliance with the state’s Act 46, which was signed by Gov. Josh Green in 2024 as a means to address Hawaii’s housing crisis statewide.
One concern about allowing two ADUs per residential lot, as expressed by the Maui Department of Fire and Public Safety, is that it could interfere with the county’s fire prevention efforts.
ARTICLE CONTINUES BELOW ADHowever, there are already checks in place to address this. The county code states that in order for a homeowner to build an ADU, the lot “must have direct access to a street that meets fire code requirements for fire apparatus access roads.” There are also other ways to regulate fire safety, such as ensuring access to fire hydrants.
The bottom line is that Maui residents need access to housing. For too long, strict laws have made it difficult to build affordable options.
ARTICLE CONTINUES BELOW ADARTICLE CONTINUES BELOW ADSimple zoning changes related to ADUs could help reverse that trend so more residents can continue calling Maui County home.”
*****Views expressed in Op-Ed pieces are those of the author’s alone and do not reflect or represent the opinions, policies or positions of Maui Now.*****
Sponsored Content
