ADU Builder in Falmouth, MA
Mussato Building Group designs, permits, and builds ADUs in Falmouth, 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 27 miles away, and we work across Falmouth Village, Woods Hole, North Falmouth, West Falmouth, East Falmouth, Teaticket, Hatchville, and Waquoit.
- Family-owned since 2004
- Licensed + insured in MA
- 100+ projects completed
- 5.0 stars from 21 Google reviews
- BBB accredited
Building an ADU in Falmouth
Falmouth covers the southwest corner of the Cape, from Woods Hole and Falmouth Village to the coves and ponds of East Falmouth and Waquoit.
State law allows one ADU of up to 900 square feet by right on most single-family lots, and that includes Falmouth. 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 Falmouth Board of Health.
“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 Falmouth
We prepare the drawings, file the applications, and schedule the inspections. Here is what a project like this usually needs:
- Building permit from the Falmouth Building Department, and a certificate of occupancy at the end.
- Review by the Falmouth 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 Falmouth 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.
- 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 Falmouth: FAQ
Can I build an ADU in Falmouth?
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 Falmouth. Setbacks, septic capacity, and conservation rules still apply, so we check your lot first.
Do you build ADUs in Falmouth Village and Woods Hole?
Yes. We build detached and attached ADUs all over Falmouth, including Falmouth Village, Woods Hole, North Falmouth, West Falmouth, East Falmouth, Teaticket, Hatchville, and Waquoit. Our base in South Yarmouth is about 27 miles away.
Will my septic system handle an ADU in Falmouth?
Falmouth Village and Woods Hole have town sewer, and most of the rest of Falmouth is on septic. On septic, Title 5 sizes the system by bedroom count, so an ADU with a bedroom can mean a septic upgrade. The Falmouth Board of Health reviews it before the building permit.
Can I rent out an ADU in Falmouth?
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 Falmouth rules before you plan on summer rentals.
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