Ajax’s rapid growth through the 1980s and 1990s left a lot of homes with builder-grade ductwork that’s now 30-plus years old, undersized trunks, loose joints, and flex runs routed in ways that made sense for the original furnace but choke a modern high-efficiency unit. David Cassar serves all of Ajax and the surrounding Durham Region communities, and he’s available same-day for repairs and emergencies.
From a single leaking joint in a finished basement to a full duct system replacement, David handles every scope of ductwork work across Ajax.
New builds and home additions in Ajax’s northwest neighbourhoods near Taunton Road often need complete duct systems sized properly from the start. David calculates the load before he touches metal, so every branch gets the airflow the room actually needs. You get a layout that works with your equipment, not against it.
Disconnected joints, collapsed flex duct, and deteriorated mastic seals are common in Ajax homes built in the late 1980s and early 1990s. David finds the problem and repairs it the same day in most cases. He stocks the materials he needs, so there’s no waiting on parts for a standard repair job.
When a duct system is too far gone to repair economically, replacement is the honest answer. David tells you which it is before work begins. A full replacement in Ajax typically takes one to two days, and the new system gets sized to match whatever furnace or heat pump you’re running now.
A yearly inspection catches small leaks and loose connections before they cost you money on heating and cooling bills all season. David checks static pressure, inspects all accessible joints, and tests airflow at the registers. It takes about an hour and it’s the cheapest way to keep your duct system performing properly.
Upgrading to a high-efficiency furnace or heat pump while keeping undersized or leaky ductwork from 1990 defeats the purpose. David assesses your existing system, identifies the bottlenecks, and upgrades only what needs upgrading. You get the efficiency gains the new equipment promises without paying to replace things that don’t need replacing.
A completely separated trunk line in January means the furnace is running but heat isn’t reaching most of the house. David picks up the phone personally when you call, and he gets to Ajax same-day for genuine emergencies. You won’t be routed to a call centre or put on a waiting list while your home gets cold.
I’ve worked in Ajax homes since 2011, and the same issues keep showing up: original builder ductwork that was sized for a 1990s mid-efficiency furnace, flex duct crammed into tight spaces in the attic, and trunks that haven’t been inspected since the house was built. I know what’s in the walls here because I’ve been opening them up for over a decade. When you call, you reach me directly, not a dispatcher, not a booking line.
Sheet metal ductwork installed properly can last 25 to 50 years. Flexible ductwork, the kind used in tight spaces or attic runs, has a shorter useful life, typically 15 to 25 years before the inner liner starts to degrade and the outer jacket cracks. Fibreglass duct board falls somewhere in between, but it deteriorates faster when it gets wet or when the HVAC system runs at higher static pressures than it was designed for.
Ontario’s climate shortens that lifespan faster than you’d see in a milder region. The combination of cold winters and humid summers causes ductwork in unconditioned spaces, attics, crawlspaces, and unfinished basements, to expand and contract repeatedly. That movement works the joints loose over time, especially where the original installation relied on foil tape rather than mastic sealant. Mastic holds. Foil tape eventually doesn’t.
The single best thing you can do to extend duct life is keep the filter clean and the static pressure in the system within spec. When a furnace or air handler fights a clogged filter, it pulls harder, and that pressure finds the weak points in the duct system first.
A focused repair, reattaching a disconnected joint, sealing a leaking flex connection, or replacing a short run of damaged flex duct, typically runs between $150 and $400 in Ajax, depending on where in the house the problem is and how long the repair takes. Attic or crawlspace work costs more than an accessible basement repair simply because of the time involved in getting there and working in a confined space.
A partial replacement, where David replaces a section of the trunk line or redesigns a branch that’s been restricting airflow, generally falls in the $600 to $1,500 range. A complete duct system replacement in a typical two-storey Ajax home, removing the old system and installing a new properly-sized layout, runs from about $3,500 to $7,000 or more depending on the size of the home, the complexity of the layout, and whether the work involves finished ceilings or walls.
Every job gets a free upfront quote before work starts. The best way to know what your specific job will cost is to get a free quote from David, no pressure, no obligation.
Most of Ajax’s residential stock was built in two distinct waves: a smaller older section near the waterfront and downtown core, with homes going back to the 1950s and 1960s, and a much larger suburban expansion that pushed north through Westney Heights, Pickering Village, and toward Taunton Road from the late 1980s through the early 2000s. The suburban homes from that second wave make up the bulk of what David works on in Ajax. They were built quickly, and the ductwork reflects that, builder-grade galvanized trunks sized for a 60,000 BTU mid-efficiency furnace that’s since been replaced by something quite different.
The older homes near downtown Ajax and the waterfront present a different challenge. Many were built without central forced-air systems at all, or were retrofitted with ductwork that had to be routed creatively around existing framing and plumbing. The result is often a system with more bends, more transitions, and more pressure drop than a properly designed installation would have. Homeowners in those areas frequently notice that rooms on the second floor or at the far end of the house don’t heat or cool as well as the rest.
Ajax also has a significant number of homes with two-storey great rooms or open-concept main floors, which became popular in the 1990s and early 2000s builds. Those open volumes are hard to condition efficiently with a single supply register, and the original duct layouts often didn’t account for the heat stratification that results. David sees this regularly and can add supplemental supply branches or rebalance the system to address it without replacing the whole thing.
The clearest sign is uneven temperatures, one part of the house that’s consistently too hot in summer or too cold in winter while the rest of the house is fine. That usually means a specific branch has a restriction, a disconnected joint, or was undersized from the beginning. In Ajax’s 1990s builds, the second-floor bedrooms at the far end of the house are the most common complaint: the trunk line runs out of pressure before it gets there, especially on systems that have been upgraded to higher-efficiency equipment with a variable-speed blower that operates at lower static.
Rising energy bills without a change in usage habits are another indicator. Leaking ductwork in an unconditioned basement or attic means you’re conditioning that space instead of the living area. Depending on how bad the leakage is, you can lose 20 to 30 percent of your conditioned air before it reaches a register. You’ll feel it in the rooms and in the utility bill, but the furnace or A/C won’t throw a fault code because it doesn’t know the air went the wrong way.
Dust accumulation near supply registers, unusual smells when the system starts, or a whistling sound from specific vents all point to ductwork issues rather than equipment problems. David can diagnose all of these on a single visit, he doesn’t charge a separate diagnostic fee on top of a repair quote.
Durham Region runs through genuine temperature extremes, design heating days well below -20°C and cooling loads that push homes hard through July and August. A duct system that’s barely adequate in shoulder-season temperatures shows its weakness during those peaks. The trunk line that delivers enough airflow on a mild October day may be losing 15 percent to leaks by the time January hits and the furnace is running continuously.
Sealing the ductwork in unconditioned spaces is the highest-value single improvement most Ajax homeowners can make. Mastic-sealing all accessible joints in a basement, then insulating the ducts running through that space, reduces heat loss to the basement and increases the amount of conditioned air that arrives at the registers upstairs. In Durham Region’s winters, that makes a measurable difference in both comfort and gas consumption.
In summer, ductwork in unconditioned attics absorbs heat and delivers warm air into rooms that are supposed to be cooling down. If you’ve got a finished attic space or any supply runs routed through an uninsulated attic, that’s worth addressing alongside any repair work. It won’t require new ductwork in most cases, proper insulation around the existing runs solves most of it.
In Ontario, any work on gas-fired heating appliances and their associated systems, including the ductwork connected to a gas furnace, must be performed by a TSSA-licensed technician. That licence exists because improper work can result in carbon monoxide entering the living space. A furnace with a cracked heat exchanger can push CO into the duct system, and poorly sealed return ductwork can pull combustion gases from a utility room into the airstream. TSSA Licence #000398183 is David’s verifiable credential, you can confirm it on the TSSA public registry before you book.
Ontario homeowners upgrading or replacing ductwork as part of a larger HVAC system change may qualify for rebates through the Canada Greener Homes initiative or Enbridge’s Home Efficiency Rebate Plus program, depending on the scope of the project and whether it includes a qualifying heat pump or high-efficiency furnace installation. David can advise on what documentation you’ll need and what work qualifies, the rebate programs change periodically, so it’s worth asking at the time of your quote.
On the efficiency side, properly sealed and balanced ductwork isn’t just about comfort. It affects the rated efficiency of your equipment. A 96% AFUE furnace running against leaky ductwork delivers far less than 96% of its energy as useful heat to your living space. Getting the duct system right is what lets the equipment perform at the spec on the rating plate.
Checking the simple things before calling saves time for everyone.
Make sure every supply vent in the home is fully open. Closed vents cause pressure imbalances that reduce performance and can damage equipment.
In basements and utility rooms, look for disconnected joints, torn flex duct, or visible gaps. Even small separations can lose significant conditioned air.
A blocked filter causes pressure imbalance across the entire duct system, making uneven heating and cooling worse. Replace it first before anything else.
Rooms consistently too hot or cold, or that take longer to reach temperature, indicate specific duct branches that are undersized, leaking, or poorly routed.
Unusual dust buildup around supply vents can indicate leaks pulling in unconditioned air from attic or wall cavities, a significant air quality and efficiency issue.
If none of the above solve it, it needs a licensed technician. David serves all of Durham Region and picks up the phone personally.
The most reliable indicators are uneven temperatures between rooms and higher-than-expected energy bills. If you’ve got a room in your Ajax home that’s always colder than the rest in winter or warmer in summer, and adjusting the vents doesn’t fix it, the duct branch serving that room is either leaking, undersized, or both. Leaking ducts lose conditioned air into unconditioned spaces like attics, crawlspaces, or finished wall cavities, you’re paying to heat or cool those spaces instead of the room you care about. Undersized ducts simply can’t deliver enough airflow, regardless of how hard the furnace works. A pressure test or airflow measurement is the definitive way to confirm it, and David can run that during a standard service call. You don’t need a separate diagnostic appointment.
A targeted repair, sealing a joint, reconnecting a flex run, or replacing a short damaged section, typically runs between $150 and $400 in Durham Region, depending on access and time. Partial replacements, where a branch or section of trunk needs to be redesigned and reinstalled, generally fall in the $600 to $1,500 range. A full duct system replacement in a typical Ajax two-storey home runs from approximately $3,500 to $7,000 or more, depending on the square footage, the complexity of the layout, and how much finished space the ductwork has to route through. Work in tight attic spaces or through finished ceilings takes longer and costs more than straightforward basement work. Older homes near downtown Ajax where the duct system was retrofitted around existing structure can also add complexity. The best way to know what your specific job will cost is to get a free quote from David, no pressure, no obligation.
Yes, leaking or restricted ductwork is one of the most common reasons a furnace or air conditioner underperforms, even when the equipment itself is in good condition. When ducts leak, the air handler works against lower-than-designed static pressure in some places and higher-than-designed pressure in others. That imbalance makes the blower motor work harder, increases wear, and in some cases causes the heat exchanger to overheat and short-cycle on the high-limit. On the cooling side, restricted airflow across the evaporator coil can cause the coil to ice over, which shuts down the A/C entirely. If your equipment is running but the house isn’t reaching setpoint, the duct system is often the first place worth looking. David checks static pressure and airflow as part of any ductwork diagnostic, he won’t recommend replacing equipment if the real problem is in the ducts.
A full duct system installation in a typical Ajax home takes one to two days for the main trunk and branch layout, with a third day sometimes needed for finishing work in more complex layouts or homes with finished ceilings. A partial installation, adding a branch to a new room addition, for example, or rerouting a section of trunk, usually takes three to six hours. The timeline depends heavily on access. An unfinished basement with open joists is fast to work in. A finished basement or attic with limited hatch access takes significantly longer because every section has to be assembled in a tight space and maneuvered into position. David gives you a realistic time estimate before work starts, not a range so wide it’s meaningless. He’ll also tell you if the work will require drywall repair so you can plan for that separately.
If the duct system is fundamentally sound, the sheet metal is intact, the layout is reasonable, and the leakage is at the joints rather than through corroded or collapsed sections, sealing with mastic is almost always the right call. It’s significantly less expensive than replacement and delivers most of the same performance gain. Replacement makes sense when the sheet metal itself has deteriorated, when the layout is so poorly designed that it causes chronic performance problems no amount of sealing can fix, or when flex duct has reached the end of its useful life and is collapsing in multiple places. In Ajax homes from the late 1980s and early 1990s, David often finds systems where the trunk is still serviceable but the flex branches are overdue for replacement, a targeted approach that replaces the flex and seals the metal is usually the most cost-effective answer. He’ll tell you which category your system falls into during the initial visit.
Hot and cold spots in an Ajax home point to ductwork issues more often than equipment problems. The two most common causes are undersized branch ducts that can’t deliver enough airflow to a specific room, and leaks in the supply runs serving those areas. Both result in the same symptom, the room takes too long to reach temperature or never quite gets there, but they need different fixes. A third possibility specific to many Ajax homes from the 1990s is poor system balance: a duct layout designed for a mid-efficiency furnace with a single-speed blower that now runs a variable-speed unit operating at lower static pressure most of the time. The system was never balanced for variable speed, so certain branches don’t get enough air at the lower operating modes. David balances duct systems as part of his installation and repair work, it’s not a separate specialty, it’s part of the job.
David focuses on ductwork installation, repair, replacement, and sealing, the structural and performance side of the duct system. Duct cleaning, which uses specialized vacuum and brush equipment to remove accumulated debris from inside the ductwork, is a separate service that David refers out to trusted duct cleaning specialists rather than offering himself. The reason is straightforward: duct cleaning done properly requires dedicated equipment that a technician focused on installation and repair doesn’t carry. David can tell you during an inspection whether your ducts look like they’d benefit from cleaning, and in some Ajax homes he’s opened up, the answer is clearly yes, particularly older systems that haven’t been serviced in 10 or more years. He’ll point you in the right direction if cleaning is warranted before or after any structural repair work.
The clearest signs are chronic room-to-room temperature differences that don’t improve with balancing, a system that was clearly routed to avoid obstacles rather than to deliver air efficiently, and flex duct runs that have sharp bends or are stretched too tight, both of which add significant resistance. In older Ajax homes near the waterfront and downtown core, David regularly finds ductwork that was added decades after the house was built, routed through whatever spaces were available rather than through a designed path. That kind of installation usually has too many fittings, too many transitions between duct sizes, and return air that’s been improvised rather than properly ducted back to the air handler. The symptom is a house that always feels slightly off regardless of what equipment is running. In those cases, a layout redesign, not just repairs to what’s there, is the only fix that actually solves the problem.
“The flex duct coming off our main trunk had completely pulled away from the boot, we were heating the basement ceiling all winter. David came out same-day and had it sealed and secured within the hour.”
“We’d had two other guys look at the hot and cold spot problem in our Ajax townhouse and neither one touched the ducts. David came in, checked the static pressure, found two undersized branches off the main trunk, and explained exactly what he was going to do before he started. He replaced those runs and balanced the system, the second floor actually heats evenly now for the first time since we moved in.”
“Quoted me $340 on the phone after I described the problem, showed up when he said he would, charged me $340. I’ve had tradespeople double their quotes on me before so I appreciate that David actually stands behind his number. He also put down drop cloths in my finished basement without me asking, it was a small thing but I noticed.”
David covers all of Durham Region, if you’re near Ajax, he can get to you.
Same-day service available. TSSA certified. Honest pricing. Call or book online.
