Home Additions on Cape Cod
Mussato Building Group designs and builds home additions across Cape Cod: room additions, second floors, garage additions, sunrooms, and in-law suites. Every addition is engineered and constructed to match your home’s existing structure, style, and quality. 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.
Whether you need more living space or a dedicated room for a growing family, we handle the drawings, the engineer’s review, the permits, and the construction, and Joe Mussato oversees every job.
- Family-owned since 2004
- Licensed + insured in MA
- 100+ projects completed
- 5.0 stars from 21 Google reviews
- BBB accredited
Room additions and second floors
A first-floor addition needs room on the lot, a foundation, and a roof that ties into the one you have. A second floor uses the footprint you already own, which matters on a small lot, but the existing framing and foundation have to carry it. We look at both and tell you which one the house and the zoning support.
Built to match
The test of an addition is whether it looks like it was always there. We match the roof pitch, the siding and trim, the window style, and the floor heights, and we plan the connection so the old and the new structure work as one.
- Room additions & second-floor additions
- Garage additions & conversions
- Sunrooms & enclosed porches
- In-law suites & bump-outs
- Living space & kitchen expansions
- Structural integration with existing home
- Permit coordination & code compliance
- Matching materials & finishes
Planning an addition on Cape Cod
Zoning first
Setbacks, lot coverage, and height decide how far a house can grow. Many older Cape homes sit closer to the lot line than today’s rules allow, and adding to one can require a hearing at the Zoning Board of Appeals.
Bedrooms and septic
Title 5 sizes a septic system by the number of bedrooms. An addition that adds a bedroom needs the Board of Health to confirm the system can take it, or an upgrade.
Flood zones
In a FEMA flood zone, an addition large enough to count as a substantial improvement means the whole house has to meet the flood standards, not just the new part.
Conservation Commission
An addition within 100 feet of a wetland, a pond, or a coastal bank needs a filing with the town’s Conservation Commission.
Historic review
In the Old King’s Highway district along Route 6A, and in the historic districts of towns like Provincetown, the exterior of an addition is reviewed before the building permit.
Tying into the house
Where the new roof and walls meet the old ones is where additions leak or settle if the work is rushed. We plan the framing, the flashing, and the foundation connection before we open the house.
“Mussato Building Group has been a loyal and trusted partner of ours for over ten years and one hundred projects. Their professionalism and quality of work are second to none. We look forward to working with them far into the future.”
Our Process
Site Assessment
We evaluate your existing structure, zoning requirements, and how the addition will integrate with your home.
Design & Permits
Drawings, engineer review, and permit acquisition, we handle it all before any work begins.
Foundation & Framing
Structural work executed to code, with attention to how the new structure connects to the existing one.
Finishing
Interior and exterior finishes matched to your existing home, right through to the final detail.
Home Additions in Our Featured Areas
- Home Additions in Osterville, MAOsterville village, Wianno, and Oyster Harbors
- Home Additions in Cotuit, MACotuit village and Santuit
- Home Additions in New Seabury, MAMaushop Village, The Mews, and Bright Coves
- Home Additions in Chatham, MAChatham Village, North Chatham, and South Chatham
- Home Additions in Orleans, MAOrleans Village, East Orleans, and South Orleans
- Home Additions in Provincetown, MAthe West End, the East End, and the Commercial Street area
Other work on Cape Cod
- Custom Home Builder on Cape CodNew homes, frame to finish, with one team
- Home Remodeling on Cape CodKitchens, bathrooms, and whole-home renovations
- Deck Builder on Cape CodNew decks, deck replacement, stairs, and railings
- Deck Replacement on Cape CodTear-out and rebuild of old, soft, or unsafe decks
- Basement Finishing on Cape CodMedia rooms, gyms, bars, guest suites, and egress windows
- Basement Remodeling on Cape CodDated or damp finished basements rebuilt from the foundation in
- Basement Egress Windows on Cape CodCode-size escape windows and window wells for basement bedrooms
- Bathroom Remodeling on Cape CodTile showers, tubs, vanities, and powder rooms
- Kitchen Remodeling on Cape CodLayouts, islands, custom cabinetry, and counters
- ADU Builder on Cape CodDetached guest cottages, in-law suites, and garage conversions
- Roofing Contractor on Cape CodRoof replacement, new roofs, and storm damage repair
- Deck Staining on Cape CodCleaning, repairs, and stain for wood decks
- Basement Waterproofing on Cape CodFinding the leak and keeping the basement dry
Home Additions FAQ
How much does a home addition cost on Cape Cod?
It depends on the size, the foundation, and how much of the new space has plumbing, like a kitchen or a bathroom. We price the job line by line after a visit and a first set of drawings.
Is it better to build up or build out?
It depends on the house and the lot. Building up avoids a new foundation, but the existing structure has to carry the load and the stairs take floor space. Building out needs room inside the setbacks. When both are possible, we price both.
Do I need a permit for a home addition in Massachusetts?
Yes. An addition needs a building permit and a zoning review, and often other approvals: the Board of Health if it adds a bedroom, the Conservation Commission near wetlands or the shore, and a historic review in a historic district.
Can you match my existing siding, roof, and trim?
Yes. Matching the existing house is how we build every addition. New cedar shingles take time to weather to the color of the old ones, and we tell you what to expect before we start.
Which towns do you build additions in?
All 15 towns of Barnstable County: Barnstable, Bourne, Brewster, Chatham, Dennis, Eastham, Falmouth, Harwich, Mashpee, Orleans, Provincetown, Sandwich, Truro, Wellfleet, and Yarmouth.
Tell Us About Your Project
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