ADUs & In-Law HomesRoom for Family. Value for the Property.
Independent living space on your lot for family, guests or long-term rental where permitted.
We check what the lot can support, then build the unit from the ground up.
- Early site & septic capacity review
- Permits & inspections coordinated
- Sitework, build & finish by one team
ADUs & In-Law Homes by Green Island
Photographs of Green Island's own work.











What we do
An accessory dwelling unit or in-law home adds independent living space on your property — for family, guests or long-term rental where permitted. We help you understand what the lot can support and build the unit from the ground up.
Why Green Island: Because we handle sitework, septic and construction, your ADU is planned as one project — not handed between separate contractors.
What's included
- Early review of the site, septic capacity and access
- Foundation and utility connections
- Framing, exterior envelope and roofing
- Kitchen, bath and interior finishes sized for the space
- Coordination of permits and inspections
- Landscaping and walkways to tie the unit into the property
How we approach the work
- Conversation and site visit — we learn the property, the goals and the constraints.
- Clear scope — what is included, what still needs to be decided and what information we need.
- Scheduled, coordinated work — one team managing the phases in the right order.
- Walk-through and follow-up — we finish what we start and stand behind it.
More New Construction work

New Home Under Construction
Our crew and trucks on site at a new home going up.
What clients say about Green Island
"Experience was great, would hire them again for any other project that I may have in the future. Price was fair, and great communication with us through the entire project."
Related services
New ConstructionServing Cape Cod, Martha's Vineyard, Nantucket & the South Shore of Massachusetts
Proudly based in Edgartown, Massachusetts.
Discuss Your ADU Project
Prompt Follow-Up. Clear Scope. Transparent Next Steps.
Complex projects may require site plans, engineering, septic information and design selections before responsible pricing can be established.