round vs rectangular ductwork

You’ve probably never given a second thought to your air ducts – but we have. Air ducts come in different sizes, shapes, and materials. Why are there so many different kinds of ducts? Because each type of air duct serves a different purpose and has different strengths and limitations. To the everyday consumer, this might come as a surprise – and it is probably slightly overwhelming. But your local HVAC professionals have all the answers to help you outfit your building with the appropriate ductwork.
You might have heard your HVAC professionals discuss round vs rectangular ductwork – but what is the difference? And which one is right for your needs?

Round Air Ducts

The Advantages of Round Air Ducts

Round, circular, or spiral air ducts are definitely the more common type of ductwork – and not without reason. There are many advantages to round ducts, from increased airflow, quick installation, and lower costs. If you’re trying to create a quiet, appealing workspace for your employees and customers, then round duct work is definitely the number one choice.

  • Less friction
  • Better, more efficient airflow
  • Easy to join pieces together
  • Faster installation
  • Better for medium to high pressure systems
  • Costs less for initial installation
  • Less noise pollution

The Disadvantages of Round Ductwork

However, certain situations do not allow for round ductwork. Why? Round ducts take up more height than do rectangular or square ducts. This means that in tight spaces, round hvac ducts just won’t fit. Round ductwork also doesn’t fully take up the available space in the same way that square ducting does, which means it’s technically less efficient in terms of maximizing airflow.

It can also become unappealing to the eye when trying to connect the fan coil to the main duct, which means connecting round to square duct openings.

  • Takes up more space (taller)
  • Not efficient for low pressure systems
  • Difficult to connect fan coil to main duct

get comfy, stay comfy

Rectangular Air Ducts

square ducting installed on a rooftop

The Advantages of Rectangular Air Ducts

So, when is it okay to use rectangular ductwork? As mentioned before, rectangular ducts are necessary whenever you’ve got a tight space that won’t allow for the height of round ducts. These rectangular or square air ducts also fix the issue of the ugly connection between fan coil and main duct.

  • Takes up less height
  • Easily connects fan coil to main duct
  • Better for low pressure systems

Rectangular or square ductwork can also look better for some applications that use exposed ductwork, such as warehouses, lofts, and bars.

The Disadvantages of Rectangular Ductwork

Okay, so why aren’t we using rectangular ductwork all the time? Well…. That’s because rectangular air ducts have a few big drawbacks. They allow for more noise to escape from the duct, which can cause a lot of problems if you’re trying to create a safe and quiet employee environment. Rectangular HVAC air ducts also cost more to install initially, which can put a dent in your company’s pocket.

  • Higher noise pollution
  • Costs more for initial installation

Round vs Rectangular Ductwork – What’s the Verdict?

So we’ve told you about the pros and cons of round vs rectangular ductwork – but what’s our final opinion? In truth, the choice in round or rectangular ductwork isn’t entirely up to you (it’s up to your HVAC expert.) But, it all depends on how much space you have, if you have exposed ducts, if you have a high or low-velocity HVAC system, and more. If you’re still unsure, you can request to have one of our trained HVAC technicians sent to inspect your property’s air ducts. If, in the process, they find that your ductwork is beyond repair, they will discuss potential air duct replacement options with you to ensure that you understand the problem. Irish Heating and Air are the HVAC pros to go to when your home need an air conditioner repair in Tracy during the summer heat or a furnace repair in Modesto, when the colder months settle in.

Need new duct work for your commercial building? Discuss all options with your commercial HVAC professional so you can get new duct work that is efficient, easy to look at, and affordable.