Metal Versus Flexible Ductwork: Advantages And Disadvantages

22 April 2020
 Categories: Business, Blog


If you are building or repairing an HVAC ductwork system, then you can choose from metal or flexible materials. If the entire system needs rebuilding, then you may want to change to an entirely different material. Which one you choose depends on several factors as well as your budget. Here are some advantages and disadvantages of both metal and flexible materials for your HVAC system.

Advantages of Flexible Ducts

In addition to lower costs, flexible ducts have many advantages in certain circumstances. Here are some examples.

They Fit In Tight Spaces

You can manipulate flexible ducts easily and place them around tight corners and turns. This makes them great for smaller buildings, like homes, with less space.

They Are Lightweight

Flexible ducts are lightweight, so they are easy to remove and replace when needed. They are unlikely to cause damage if they become unattached or fall.

They Are Easy to Install

Flexible ducts are easy to install and often do not need to be custom-made or fitted. You don't even need a large tool selection to install them.

Disadvantages of Flexible Ducts

Flexible ducts aren't always the best choice in all situations. Here are some downsides of flexible ducts.

They Need Support

Flexible ducts are great if you keep them short and supported. Long lines of flexible ductwork will sag and possibly kink. They could result in airflow restrictions and contribute to leaks.

They Are Not Durable

While flexible materials can last for years, they are not as durable as more rigid materials like fiberglass or metal. Soft material is more likely to suffer deterioration that could open up holes and let the warm or cold air escape.

Advantages of Metal Ducts

Metal ducts are generally made of sheet metal or aluminum. However, other types of rigid materials, like fiberglass, are also often used. Metal ducts conduct heat well and have many other advantages including the ones listed below.

They May Fit Better

You can order your metal ductwork that is custom-made for your HVAC system. This allows for a perfect fit.

They May Leak Less

Metal ductwork tends not to tear or break down as easily as flexible ductwork. As long as the joints are well-connected, they are much less likely to leak. Make sure you connect the joints tightly and seal them up. You can also cover your ducts with insulation to further reduce any chance of leaks.

They Last Longer

Metal is extremely durable and could even last for the life of your home depending on what type of metal you choose. Regular cleaning and inspections increase this longevity.

Disadvantages of Metal Ducts

Metal ducts may not be appropriate or feasible for all projects. While their disadvantages are few, they do exist and should be taken into consideration.

They Are Less Flexible

You must have enough room available to run your metal ductwork. Most metal ductwork cannot fit in tight spaces or corners in the same way as flexible ductwork.

They May Be Prone to Mold or Rust

Most types of metal ductwork resist contaminants like mold or rust. Some are specifically designed to resist moisture. However, some types of metal do accumulate these substances, especially on the inside of the ducts. This can be remedied by regular duct maintenance.

They Transmit More Noise

Noise echos and travels around metal ducts more easily than the soft material of flexible ducts. If your building shares air ducts between tenants, then some people may not like this additional noise.

In most cases, the type of air duct material you use should depend on your project size and its difficulty. A regular-sized house is obviously going to be a different situation than a large building. For more information about HVAC materials, contact an HVAC supply store