Building an ADU on Martha’s Vineyard

Yes, ADUs are allowed on Martha’s Vineyard, but rules vary by town such as Edgartown, West Tisbury, Chilmark, Oak Bluffs, and Tisbury. Each town has its own zoning bylaws governing size, placement, usage, and permitting. Some properties may also be affected by conservation, coastal, or watershed regulations.

On Martha’s Vineyard, ADUs are most commonly used as guest houses, in-law apartments, caretaker residences, or flexible overflow living space during the summer season. Many homeowners build ADUs to support multigenerational living while maintaining privacy and preserving the character of the main home.

Rental rules for ADUs vary by town and may restrict short-term rentals. Some towns allow long-term rentals only, while others require owner occupancy or special permits. Understanding local rental bylaws early in the design phase is critical to ensure the ADU can be used as intended.

ADU costs on Martha’s Vineyard are influenced by site access, foundation requirements, utility connections, coastal or conservation reviews, and finish level. Detached ADUs and guest houses typically cost more than garage conversions or additions, especially when year-round construction and higher wind or flood zone standards apply.

The ADU timeline typically includes design, zoning review, permitting, construction, and inspections. Because Vineyard projects often involve additional regulatory review, planning timelines can be longer than mainland builds. Working with a local builder familiar with Vineyard processes helps avoid delays.