The ducts have a maximum lifespan of 20 to 25 years. However, at age 15, it begins to deteriorate, significantly reducing the efficiency of your HVAC system, so replacing it is the most prudent option. The ducts are designed to last 10 to 15 years on average. They are made of a combination of materials such as fiberglass and plastic.
Even if your HVAC system is working well, if the ducts aren't maintained, the results can be poor air quality and lower efficiency. An essential part of the routine maintenance of your HVAC system includes making sure that the ducts are clean and undamaged. Then, when your duct network isn't well maintained, you could end up needing the repair and replacement of the ducts. The NADCA also recommends replacing ducts every 10 to 15 years.
Extenuating circumstances could shorten that lifespan and require earlier replacement. That's why it's so important to hire the right commercial HVAC maintenance company to ensure that the key components of your HVAC system aren't neglected.