Whole-system duct and dryer vent check with before-and-after photos - you see exactly what came out of your vents
That "$99 whole-house special" is a bait ad - the real number appears once they are in your hallway, or the "clean" is a shop-vac at the register. We photograph the inside of your ducts before and after instead.
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AfterTrusted Duct Sealing Nationwide
If your energy bill keeps climbing while a few rooms stay too hot or too cold, the problem is often not your furnace or air conditioner. It is the ducts. In a typical home, a surprising share of conditioned air escapes through gaps, loose joints, and cracked seams before it ever reaches a room, and it leaks into attics, crawlspaces, and wall cavities where nobody benefits from it. Morton’s Air Duct Cleaning has been finding and closing those leaks in homes across the country since 2005. Every job starts with a written price before we touch anything, and a 365-Day Done Right Promise stands behind the work. Call (323) 918-4345 and a live person answers, any hour, any day.
Duct Sealing Services
Duct Sealing Services close the holes, gaps, and loose connections in your home’s ductwork so the air your system heats or cools actually arrives in the rooms you live in. Ducts leak at every joint, at the boots where they meet the registers, at the plenum next to the furnace, and wherever an old piece of tape has dried out and let go. Morton’s technicians locate those leaks, seal them with the right materials for each spot, and test the result so you are not taking our word for it. Most homes need sealing at a handful of accessible points, and the job usually takes between two and five hours. Typical duct sealing runs $400 to $1,200 depending on how much ductwork is reachable and how many leaks we find. You see the written price before any work starts, and it does not change when the invoice arrives. If the ducts are also dirty, pairing the work with an Air Duct Cleaning visit saves a second trip.
Mastic and Foil Tape Sealing
We seal seams and joints with water-based mastic and UL 181 rated foil tape, the materials that hold up for years. Ordinary cloth duct tape dries out and peels in a few seasons, so we do not use it on your system.
Register Boot and Plenum Sealing
The biggest leaks tend to hide where ducts meet the registers and where the main trunk meets the furnace or air handler. Our technicians seal those connections first, because a small gap there wastes more air than a dozen pinholes down the line.
What happens when you call
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A real person answersNo phone trees, you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
HVAC Duct Sealing
HVAC Duct Sealing treats the ductwork as one connected system with your furnace, air handler, and coil, not as a pile of separate pipes. Leaks on the supply side push cooled or heated air into spaces you never use. Leaks on the return side pull dusty attic or crawlspace air straight into the system and then into your rooms. Both problems make the equipment run longer for the same comfort, which shortens its life and raises your bill. Morton’s has worked on residential HVAC ductwork since 2005, and our technicians check the supply plenum, return plenum, and every accessible trunk connection during the same visit. For a standard single-system home, HVAC Duct Sealing generally runs $450 to $1,000. The written quote spells out which connections we plan to seal, so you know exactly what you are paying for.
Supply Side Leak Sealing
Supply leaks waste the air you already paid to heat or cool. We trace the runs that feed the rooms with weak airflow first, since those are usually where the worst gaps are, then work back toward the main trunk.
Return Side Leak Sealing
A leaky return pulls in whatever is nearby: insulation fibers, attic dust, garage fumes, or damp crawlspace air. Sealing the return side keeps that air out of your home and takes strain off the blower.
Duct Insulation
Duct Insulation keeps the air inside your ducts at the temperature you set, which matters most for runs that pass through unconditioned attics, crawlspaces, and garages. A bare or poorly wrapped duct in a hot attic can lose a meaningful share of its cooling before the air reaches the register. We seal first and insulate second, because wrapping insulation around a leaking duct only hides the problem. Morton’s installs foil-faced duct wrap and replaces damaged or missing insulation on accessible runs. Insulating a typical set of attic ducts runs $500 to $1,500, depending on length, access, and the R-value your climate calls for. Once the wrap is on, the ducts also sweat less in humid weather, which cuts down on moisture stains on ceilings below.
Attic and Crawlspace Duct Wrap
Attic runs take the worst temperature swings in the house. We wrap them tightly with the right thickness for your region and tape every seam so the wrap does not slip or gap over time.
Replacing Torn or Missing Insulation
Rodents, old age, and past repair work leave bare patches that nobody notices. We find those spots, remove what is damaged, and rewrap the section so the run is covered end to end.
Duct Repair
Duct Repair covers the damage that sealing alone cannot fix: crushed sections, disconnected runs, torn flex duct, and sagging lines that have pulled away from their fittings. A duct that has fully separated from the boot can dump an entire room’s worth of air into the wall, and no amount of mastic closes a gap that wide. Our crew reconnects the run, re-supports it with proper hangers, and then seals every joint along the way. Small repairs typically cost $150 to $400, while replacing a long damaged section can reach $300 to $800 depending on length and access. If a run is beyond saving, we will tell you and explain the options on our Air Duct Repair page, or discuss a full Air Duct Replacement when that is the honest answer.
Reconnecting Separated Ducts
Vibration and settling pull duct runs loose from their collars over the years. We refit the connection, secure it mechanically with screws or straps, and seal it so it stays put.
Re-Supporting Sagging Runs
A flex duct that droops between supports kinks, restricts airflow, and puts stress on every joint. New supports at the right spacing give the air a straight path and take the load off the seams we just sealed.
Air Duct Sealing
Air Duct Sealing is the whole-system version of the job, aimed at homes where leaks are spread throughout the ductwork rather than concentrated in one or two places. Older houses, homes with finished basements, and homes where past remodels cut into the ducts often fall into this group. In these cases we use a combination of hand sealing at every reachable joint and, where the layout calls for it, a more thorough approach that treats the full run. A full air duct sealing job for a typical single-family house runs $700 to $1,800. Before we start, we measure the leakage so there is a starting number, and after we finish we measure again. That before-and-after reading is the proof that the work did something, and we hand it to you with the invoice.
Leakage Testing Before and After
Guessing at leaks wastes time and money. Testing tells us how much air the system loses, where it is going, and whether the sealing actually closed the gaps we found.
Sealing Hard-to-Reach Joints
Some joints sit behind drywall, under insulation, or in tight chases. We tell you up front which ones we can reach and which would need an opening, so there are no surprises on the day of the job.
Signs You Need Duct Sealing
- Your energy bills rise while your habits stay the same. Leaky ducts force the system to run longer to hit the same temperature, and the extra run time shows up on every monthly bill.
- Some rooms are always hotter or colder than the rest. When the air leaks out before it reaches the far end of a run, the rooms at the end get the least. Sealing usually evens things out.
- The house is dusty no matter how often you clean. Return leaks pull attic and crawlspace dust into the system. If surfaces coat over again within days, that dust may be coming through the ducts.
- You hear whistling or rattling near the vents. Air escaping through small gaps often makes a noise. Loose, vibrating ductwork can rattle every time the fan starts.
- Your attic or crawlspace feels oddly warm or cool in the wrong season. Conditioned air spilling out of the ducts changes the temperature of the space around them. A cool attic in July is a sign that your air is going somewhere other than your living room.
Our Process, Step by Step
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Inspection and written quote. We look over the accessible ductwork, check the plenums and boots, and note every leak and damaged section. You get a written price before anything gets touched, and that number does not change on the invoice.
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Protect the floors and furniture. Shoe covers go on at the door, drop cloths go down from the entry to the work area, and anything near the registers gets covered. The house stays clean before, during, and after.
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Test the leakage. We measure how much air the system is losing before we seal, so we have a real starting point and not a guess.
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Seal, repair, and insulate. Joints, seams, boots, and plenums get mastic or foil tape. Damaged sections are reconnected or replaced, and exposed runs are wrapped where the quote includes it.
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Final test and walk-through with photo proof. We test again, show you the before-and-after, and leave you with photos of the finished work. If anything is not right, the 365-Day Done Right Promise means we come back and make it right.
How Much Does Duct Sealing Cost?
Duct sealing for a typical single-family home runs $400 to $1,200. A focused job that closes a few accessible leaks at the plenum and register boots sits at the low end. A whole-home air duct sealing job with leakage testing on both sides generally lands between $700 and $1,800. Add insulation on attic runs and the total usually reaches $500 to $1,500 for the wrap alone, and repairs to damaged sections run $150 to $800 depending on length and access.
Three factors move the price: how much of the ductwork you can reach, how many leaks we find, and whether repairs or insulation are needed alongside the sealing. You avoid overpaying by getting a written quote before work starts and by asking what is included. A bargain quote that tapes a few visible joints and leaves the plenum untouched is not a deal, it is half a job. Morton’s free estimate covers the whole system in one honest number.
Where We Work
Morton’s Air Duct Cleaning serves homeowners and businesses across the United States through local crews who work to the same Cedarwell Care Promise on every single job. Each location is independently owned and chooses to work to that standard: written pricing, shoe covers, drop cloths, photo proof, and a year-long promise behind the work. Wherever you are, the process is the same.
Frequently Asked Questions About Duct Sealing
Duct sealing is the process of closing leaks, gaps, and loose joints in your home’s ductwork using mastic and foil tape. It keeps heated and cooled air inside the ducts until it reaches your rooms. At Morton’s, every job starts with a written price and ends with a walk-through so you can see the finished work.
Most homes take between two and five hours, depending on how much of the ductwork is reachable and how many leaks we find. Larger homes, or jobs that include insulation and repairs, can take most of a day. You get a time estimate with your written quote.
A typical home runs $400 to $1,200, with a full whole-home job landing between $700 and $1,800. Insulation and repairs are quoted separately so you only pay for what your ducts need. Call (323) 918-4345 for a free estimate with a written price.
Cleaning first is usually the better order, because it lets us see every joint and seam clearly and gives the sealant a clean surface to grip. We can do both in a single visit, and our HVAC Cleaning service covers the furnace, blower, and coil at the same time.
Usually, yes. When less air escapes, your system runs fewer minutes to reach the same temperature. The size of the savings depends on how leaky the ducts were to begin with, which is why we test before and after and show you both readings.
Every job carries the 365-Day Done Right Promise. If the work is not done right within a year, we come back and make it right at no charge. It is stamped on every job, not offered only when someone asks.
Schedule Your Duct Sealing Service Today
Ready for steadier temperatures and a lower energy bill? Call (323) 918-4345 and talk to a live person, any hour of any day. You get a free, no-obligation estimate with a written price before any work begins. Every job is backed by the 365-Day Done Right Promise and the Cedarwell Care Promise, because the way a crew treats your home matters just as much as how tight the ducts are when they leave. You can also start at our home page to see everything we do.
Written by Paul Adeyemi, owner at Morton’s Air Duct Cleaning, serving homes and businesses nationwide since 2005.