There are two steps to improving the efficiency of your ductwork. The first is to have your ductwork sealed by using a compound to plug any gaps in the ductwork joints. The second step is to install duct insulation. These steps are particularly important in duct runs that travel through unconditioned spaces. These areas include the attic, garage, and crawl space.
Ductwork is made of thin metal, which conducts heat and can impact the temperature of the air running through it. On bitter cold New Jersey winter nights, heated air traveling through uninsulated ductwork in the attic is subject to these cold temperatures. The outcome is a “cold blow,” which is when the air exits supply vents at a lukewarm temperature. This scenario results in about 30 percent heat loss, and the opposite can also occur in the summer when air-conditioned air is heated by hot attic air.
Heating and cooling technicians usually select foil fiberglass insulation for ducts. This type of insulation can withstand high temperatures, making it ideal for insulating ducts with heated air traveling through them. In New Jersey, the recommended amount of insulation is measured in heat flow resistance or R-value. Your goal should be to achieve between R-8 and R-11 on your attic ductwork.
You can also install duct insulation around ducts traveling through the conditioned spaces of your home to prevent condensation from forming on the metal walls. You need as little as half an inch to provide the necessary amount of insulation.
Foil fiberglass insulation is wrapped around the ductwork with its aluminum air barrier and water retarder on the outside. The insulation itself is made of fiberglass or mineral wool. Joints between the insulation are sealed with a special kind of tape or mastic compound.
By adding duct insulation, you enjoy lower energy bills and a more evenly heated home. To learn more, please contact us at Pipe Works Services in Chatham.