What is the purpose of duct insulation?

The purpose of duct insulation is primarily to prevent heat loss or gain as air travels through ducts. Insulation plays a crucial role in maintaining the temperature of the air being transported, ensuring that conditioned air (either heated or cooled) reaches its destination without significant thermal energy loss. This is particularly important in maintaining energy efficiency within heating, ventilation, and air conditioning (HVAC) systems. By minimizing heat transfer between the air inside the ducts and the surrounding environment, insulation helps improve energy usage, reduce heating and cooling costs, and enhance overall system performance.

The other choices focus on aspects that, while relevant in the context of HVAC systems, do not encapsulate the main purpose of duct insulation. For example, reducing noise from airflow relates more to sound attenuation materials than insulation per se. The notion of allowing air expansion within ducts pertains to airflow dynamics rather than thermal efficiency. Finally, securing ducts in place refers to structural support rather than the insulating function, which is designed specifically to manage heat transfer.