ADU Builder in Barnstable, MA
Mussato Building Group designs, permits, and builds ADUs in Barnstable, MA, from detached guest cottages to in-law suites and garage conversions. We are a family-owned general contractor founded in 2004, with more than 100 projects completed and a 5.0 rating from 21 Google reviews. Our base in South Yarmouth is about 6 miles away, and we work across Hyannis, Barnstable Village, West Barnstable, Centerville, Osterville, Marstons Mills, and Cotuit.
- Family-owned since 2004
- Licensed + insured in MA
- 100+ projects completed
- 5.0 stars from 21 Google reviews
- BBB accredited
Building an ADU in Barnstable
Barnstable is the largest town on Cape Cod, with seven villages that run from the Route 6A homes of Barnstable Village to the harbors of Hyannis, Osterville, and Cotuit.
State law allows one ADU of up to 900 square feet by right on most single-family lots, and that includes Barnstable. What usually decides the project here is the lot and the septic system: an ADU with a bedroom adds to the bedroom count the system has to carry under Title 5, so we start with the Barnstable Board of Health.
In the Old King’s Highway district of Barnstable along Route 6A, a detached ADU that can be seen from the street also needs a certificate from the OKH committee, so we design the cottage to fit the historic houses around it.
“As the General Manager of Pretty Picky Properties I’ve had the pleasure of working with Joe and his team for nearly 10 years. Joe’s carpentry skills are unmatched. He’s always respectful, finishes on time, priced well, and transparent from start to finish. You will not regret hiring Mussato Building Group.”
ADU permits in Barnstable
We prepare the drawings, file the applications, and schedule the inspections. Here is what a project like this usually needs:
- Building permit from the Barnstable Building Department, and a certificate of occupancy at the end.
- Review by the Barnstable Board of Health of septic capacity under Title 5 if the ADU adds a bedroom.
- Zoning review of setbacks, height, and lot coverage under the Barnstable zoning bylaw.
- Conservation Commission review if the ADU is within 100 feet of a wetland, coastal bank, dune, or salt marsh.
- Flood-zone design if FEMA maps the lot in an AE or VE zone.
- A certificate from the Barnstable Old King’s Highway committee if the ADU can be seen from a public way in the historic district.
- Detached ADUs and guest cottages
- Attached ADUs and in-law suites
- Garage and lower-level conversions
- Kitchens and bathrooms sized for small spaces
- Foundations, framing, and exteriors matched to the main house
- Heat, hot water, and electrical for a second dwelling
- Zoning, septic, and permit coordination
- Site work and paths between the houses
ADU Builder in Barnstable: FAQ
Can I build an ADU in Barnstable?
In most cases, yes. State law allows one ADU of up to 900 square feet, or half the size of the main house if that is smaller, by right on single-family lots in Barnstable. Setbacks, septic capacity, Old King’s Highway review, and conservation rules still apply, so we check your lot first.
Do you build ADUs in Hyannis and Barnstable Village?
Yes. We build detached and attached ADUs all over Barnstable, including Hyannis, Barnstable Village, West Barnstable, Centerville, Osterville, Marstons Mills, and Cotuit. Our base in South Yarmouth is about 6 miles away.
Will my septic system handle an ADU in Barnstable?
Parts of Hyannis are on town sewer and the town is extending sewer to other villages, but most homes in Barnstable still use septic systems. On septic, Title 5 sizes the system by bedroom count, so an ADU with a bedroom can mean a septic upgrade. The Barnstable Board of Health reviews it before the building permit.
Can I rent out an ADU in Barnstable?
Long-term rentals are allowed, and the town cannot require you to live on the property. Short-term rentals of an ADU can be restricted by the town, so check the Barnstable rules before you plan on summer rentals.
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