Why Ductwork is the real key to energy efficient homes

Why ductwork is the real key to energy efficient homes. Everyone with a forced air heating and cooling system has felt it at one time or another. In the summer your basement feels like a cold storage meat locker, and your bedrooms on the second floor feel like a hot day in Aruba! You call your friendly local HVAC company ( maybe AirPlus Canada?) and the certified competent technician tells you that your furnace/air handler and split air conditioning system is working properly. You have a hard time believing it, why is the basement so cold and the upstairs so hot? There MUST be something wrong with the system! The answer, of course, is that there IS A PROBLEM, but the problem is likely not with your HVAC appliances, but the air delivery system throughout your home.


Forced air systems use the power of the blower fan in your furnace or air handler to distribute cool comfortable air in the summer, and warm air in the winter throughout your home. There are two components to your air handling system, the Supply Air, which takes the the conditioned air at the cooling coil or heat(ing) exchanger and supplies your home with comfort, and the Return Air, which draws the spent air from your home and provides input air into the conditioning system. The supply air ducts and return air ducts work together to create an Air Circulation System in your home, very similar to the blood circulation system we have in our bodies. If our Air Circulation System is blocked, impeded or poorly designed, we will have sub optimal air circulation throughout the home – again somewhat similar to cardio vascular issues we may personally experience.

When homes are originally designed and built, they are built with the air circulation system in mind. Ducting runs throughout your home to deliver comfortable supply air to each living area AND return air ducts are installed to bring spent air back to the furnace or air handler to be filtered and re-conditioned. Over time, renovations and household furniture placement will affect this initially designed circulation system, resulting in an imbalance of either Supply or Return Air. The imbalance can cause your hvac appliances to run longer than they were designed, resulting in poor energy efficiency , excess wear and tear , and shorter appliance life.


Additionally, the ducting itself may contribute to energy loss. Sheet metal ducting is, generally, a poor delivery method for energy, especially when the ducting is not insulated, or is not contained within an insulated chamber. Shifting, punctures, and blockages will also result in energy loss. Recent studies have shown that energy efficiency can decline as much as 40% through a poorly designed and maintained ducting system. 40% ! This means that the 97% efficient furnace that you just paid for is actually going to deliver as low as 57% efficient energy value to some parts of your home, and your new 16 SEER Air Conditioner, may actually be only providing 10 SEER energy value!.

What can you do to improve your ducting? The first step is to call AirPlus Canada for a consultation. We can visit and provide a preliminary inspection and advice. AirPlus can create a plan including repair and redesign that ensures maximum comfort and efficiency of your Air Circulation System.  You can also purchase interior duct sealing – a process that injects safe compounds into your supply ducts that seal any small punctures or breakages. You can also insulate any known exposed supply ducting, by purchasing  duct insulation from your local hardware store.

If you think you may have a ducting problem, call us at AirPlus Canada at 416.298.6874 – we’d be delighted to help!

Quick Tip: In the summer, close off or block all of your basement and first floor supply vents ( we use big books and magazines) – then open all the vents on the top floors and keep your interior doors open during the day – this will force more cold air to the top of the house where it will more naturally flow down throughout your house – this idea is free, and it works for us! Have a happy summer!


Comments are closed.