Duct sealing
Mastic and tape on every joint. Aeroseal injection if access is limited. A typical home leaks 25–40% of conditioned air — we cut that to under 5%.
Ductwork —
fix the part nobody else wants to touch.
Cold rooms? Hot upstairs? Whistling registers? It's almost always the ductwork. We measure, redesign, seal, and rebalance — the work most contractors skip.
- Manual D duct design
- Aeroseal & mastic sealing
- Static-pressure tested
Master Plumber #MP176295.0 on GoogleOpen 24 hours
Same-day callback
Get a quote on ductwork repair & replacement
30 seconds. Rob calls you back personally.
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What we do
Repair, replace, or redesign — whatever the diagnosis is.
Ductwork is invisible, undersized in most homes, and full of leaks. Fixing it has a bigger impact on comfort and bills than upgrading the equipment.
Duct replacement
Old, crushed, or undersized ducts replaced with proper sheet metal or insulated flex. Sized per Manual D for your equipment.
Adding runs / supplying problem rooms
That bedroom over the garage that won't cool? Usually a duct sizing or run-length issue. We diagnose with static pressure measurements and add or upsize as needed.
Static pressure & balancing
We measure static pressure at the air handler — most homes are over the equipment's rated max, which kills capacity and burns out blowers. We fix root causes, not symptoms.
How it works
From phone call to walkthrough — done right.
1. Diagnose with measurement
Static pressure, supply/return splits, room-by-room CFM. We don't guess — we measure first.
2. Recommend the smallest fix
Sometimes it's $200 of mastic. Sometimes it's a full redesign. We recommend the smallest fix that solves the actual problem.
3. Clean execution
Floors and furniture protected. Drywall patches done cleanly. We work fast and tidy.
4. Verify performance
Re-measure after the fix to confirm we hit the target — proper static pressure, balanced room CFM, no whistling.
Why Competitive
We don't promise quality. We deliver it.
We size it for your house, not the catalog
Manual J load calc on every install — most contractors skip it. Wrong size = short cycling, comfort issues, and 20% wasted fuel.
Mass Save rebates handled for you
We're a registered Mass Save partner. Up to $10,000 in rebates on qualifying heat pumps and high-efficiency boilers — we file the paperwork.
Owner on every install
Rob is a Master Plumber (MA #MP17629). He's on every install personally — not a sales rep, not a sub.
Clean, labeled, serviceable
Our installs are diagrammed, labeled, and tidy. The next tech who walks in (even if it's not us) can service the system without guessing.
FAQ
Common questions about ductwork repair & replacement.
Why is one room always hot or cold?
Almost always a ductwork issue — undersized run, long flex with kinks, leaks at the boot, or a return air problem. Static pressure measurement narrows it down fast.
What does duct sealing cost?
Spot mastic-sealing major joints typically runs $400–800. Whole-home Aeroseal injection is $1,500–3,500 depending on the home. Both pay back in lower bills within a few years.
Should I replace my ducts when I replace my AC?
If the existing ducts are 30+ years old, leaky, or undersized, yes — putting a new SEER 18 unit on bad ducts is throwing money away. We'll measure before quoting.
More cooling services
Other cooling work we handle.
Reviews on Google5.0Don't take our word for it. Take theirs.
From neighbors across Lakeville, Plymouth, Newton, Needham, Wellesley and beyond.
“Rob's work is top notch. I'm a picky engineer. His choice of equipment, materials and his workmanship was excellent. In the bidding process, Rob was responsive, honest, competent, creative, and respectful.”
“He answered his phone at 6:30am. Within 15 minutes, Rob called and told me how to repair it myself — he did not take advantage of the situation. Saved me $300.”
“Rob was very professional and did an excellent job. Far surpassed my expectations. Will use him again in the future.”
“I recommend Rob with my highest level of support! Rob has installed multiple systems for me over the years.”
“His professionalism and craftsmanship went above and beyond what we expected. Highly recommend!”
“Great about keeping me in the loop. Very polite & respectful. Rob cleaned up on his way out — even brought his own vacuum.”
“Professional, very neat and orderly. Came when he said he would and did a great job.”
“Competitive Plumbing and HVAC was very responsive. I consulted with them and they did exactly what I wanted.”
Read more reviews on GoogleWhere we've done work
Based in Lakeville. We serve it all.
Every red dot is a job we've completed. We're rooted in Lakeville and travel across Massachusetts — don't see your town? Call us, we probably cover it.
- Lakeville, MAHQ
- Berkley, MA
- Boston, MA
- Plymouth, MA
- Bourne, MA
- Sandwich, MA
- Newton, MA
- Needham, MA
- Wellesley, MA
- Headquarters
- Service area
- Past job
Open right now
(508) 944-7623Ready to get it done right?
Call us. We answer 24/7 — and we'll tell you straight up what it takes to fix it.