Ducting is an approach to air management that uses a series of metal or plastic pipse to carry heated or cooled air from one place to another. A duct system is often referred to as ductwork. Ducts are conduits or passages used in heating, ventilation, and air conditioning (HVAC) to deliver and remove air. The needed airflows include, for example, supply air, return air, and exhaust air. Ducts commonly also deliver ventilation air as part of the supply air. As such, air ducts are one method of ensuring acceptable indoor air quality as well as thermal comfort