Which material is commonly used for duct insulation?

Fiberglass is a commonly used material for duct insulation in HVAC systems due to its excellent thermal resistance properties and sound-attenuation capabilities. The structure of fiberglass allows it to trap air, which serves as a natural insulator, helping to maintain the temperature of the air inside the ducts. This feature reduces energy loss, thus improving the overall efficiency of HVAC systems.

Furthermore, fiberglass insulation is lightweight and flexible, making it easier to install in various duct configurations. It also resists moisture, which helps prevent the growth of mold and mildew, safeguarding indoor air quality.

In contrast, materials like wood, plastic, and metal do not provide the same level of thermal insulation as fiberglass. Wood is not typically used due to its organic composition, which can be prone to deterioration and does not effectively insulate air ducts. Plastic lacks the structural strength and insulation properties suitable for high-temperature applications, while metal is conductive and can lead to heat loss. Thus, fiberglass stands out as the optimal choice for insulating ducts.