Serving South Coast, Cape Cod & Islands | M-F: 9 to 4 | (781) 831-1234
Family-owned • Mass Save® contractor • Since 2007
McMahon is a family-owned crew sealing up drafty homes across the South Shore, South Coast, and Cape Cod & Islands. With 60+ years across insulation, carpentry, and roofing, we’ll do it right the first time. Plus most jobs are covered by Mass Save®.
McMahon Services
Insulation, mold remediation, and the carpentry or roofing that often comes with them. One licensed crew handles the whole job so you have peace of mind the entire job done and done right.
Weatherization
Air sealing, insulation, and Mass Save guidance for homes losing heat, leaking air or costing too much to heat and cool.
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Spray Foam
Spray foam for attics, crawlspaces, rim joists, and other areas that need stronger air sealing and tighter insulation coverage.
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Mold Remediation
Mold-related work when moisture, musty odors or visible problem areas need direct remediation, not a temporary patch.
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Repair Support
Carpentry and roofing support when openings, roof conditions or related repairs need to be handled alongside the main scope.
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Don’t see your project? Talk to us
How Mass Save® Works
Mass Save® is a Massachusetts utility program funded by every customer’s bill. It covers most of the cost of weatherizing your home but most homeowners don’t know how much. We’ve been a Mass Save® contractor for years, so we’ll tell you up-front what your home qualifies for.
Mass Save® Contractor
Approved installer for Massachusetts’ utility-funded weatherization program. We handle the paperwork.
BPI-Certified
Trained and tested in building science and home performance, not just installation.
Licensed & Insured
Massachusetts Home Improvement Contractor. Fully insured for every home and every job.
60+ Years in the Trades
Three generations of insulation, carpentry, and roofing experience. Family-owned since 2007.
South Shore to Cape Cod
Local crew based in Carver, MA. Serving the South Shore, South Coast, and Cape Cod & Islands.
Homeowner reviews
Google Business Profile
Based on 43 verified reviews
Common Questions
McMahon answers common questions about cost, service area, Mass Save, and which type of work fits the home before a quote is scheduled.
Often, yes. Mass Save covers 100% of air sealing in most homes and 75–100% of insulation work. The Mass Save energy assessment that determines what you qualify for is also free. See what Mass Save covers.
It usually starts the process. A free Mass Save home energy assessment identifies what your home qualifies for, then we handle the work and the paperwork. You see the rebates and incentives applied directly to your job. More on the Mass Save process.
We work across most of the South Shore, South Coast, and Cape Cod & Islands from our base in Carver, MA. That includes Plymouth, Carver, Marshfield, Duxbury, Pembroke, Hanover, Norwell, Hingham, Kingston, Wareham, Marion, Mattapoisett, Fairhaven, Dartmouth, Lakeville, Middleboro, Bourne, Sandwich, Falmouth, Mashpee, Barnstable, Yarmouth, and most surrounding towns. If you’re nearby and not sure, call or email and we’ll let you know.
Yes. Most homes lose serious heat through air leaks and under-insulated attics. After insulation and air sealing, homeowners typically notice it right away: less drafty, easier to heat, and lower monthly bills. See how Mass Save weatherization works.
Call, email, or send a quote request with your town, what you’re trying to fix, and a short note about the home. We’ll follow up to schedule a Mass Save assessment or come take a look.
Ready when you are
Most projects start with a free Mass Save home energy assessment. Share your town and what you’re trying to fix — we’ll let you know whether insulation, weatherization, spray foam, mold work, or repair support is the right next step.
No-pressure quotes Family-owned South Shore & Cape Cod
