ADU Builder in Brewster, MA
Mussato Building Group designs, permits, and builds ADUs in Brewster, 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 10 miles away, and we work across West Brewster, Brewster Village, and East Brewster.
- Family-owned since 2004
- Licensed + insured in MA
- 100+ projects completed
- 5.0 stars from 21 Google reviews
- BBB accredited
Building an ADU in Brewster
Brewster sits on the bay side of the Lower Cape, with sea captains’ houses along Route 6A and quiet neighborhoods around its freshwater ponds and Nickerson State Park.
State law allows one ADU of up to 900 square feet by right on most single-family lots, and that includes Brewster. 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 Brewster Board of Health.
In the Old King’s Highway district of Brewster 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.
“I’ve worked with Joe and his team on several projects and the workmanship is consistently excellent. Their attention to detail and the ease of communication is second to none. Highly recommended.”
ADU permits in Brewster
We prepare the drawings, file the applications, and schedule the inspections. Here is what a project like this usually needs:
- Building permit from the Brewster Building Department, and a certificate of occupancy at the end.
- Review by the Brewster 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 Brewster 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 Brewster 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 Brewster: FAQ
Can I build an ADU in Brewster?
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 Brewster. Setbacks, septic capacity, Old King’s Highway review, and conservation rules still apply, so we check your lot first.
Do you build ADUs in West Brewster and Brewster Village?
Yes. We build detached and attached ADUs all over Brewster, including West Brewster, Brewster Village, and East Brewster. Our base in South Yarmouth is about 10 miles away.
Will my septic system handle an ADU in Brewster?
Brewster homes are on septic systems, so a new bedroom always starts with the septic design. On septic, Title 5 sizes the system by bedroom count, so an ADU with a bedroom can mean a septic upgrade. The Brewster Board of Health reviews it before the building permit.
Can I rent out an ADU in Brewster?
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 Brewster rules before you plan on summer rentals.
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