Insulating Ductwork In Attic Venting

Make sure the foil surface of the insulation is free of dust before applying the tape.

Insulating ductwork in attic venting.

Purchase duct wrap insulation that complies with the 2009 international energy conservation code iecc standards that specify an r value of 8 for attic ducts and 6 for ducts located anywhere else. Ted also has inherited a powered attic ventilator. Because the moving air is in the ductwork for only a short period of time it does not need the insulation r value the attic floor requires. When hvac ducts are installed in a vented attic in a dry climate bury the ducts in attic insulation to protect them from temperature extremes in the unconditioned attic space.

The greater the temperature extreme between the air inside the duct and the air surrounding the ductwork the greater your need for duct insulation. Although both the attic floor and the ductwork are insulated ted recognizes the situation isn t ideal. Use the type of metallic foil duct tape recommended by the insulation manufacturer to seal and hold the insulation in place. Unfortunately so many houses especially newer homes end up with ductwork running through the attic.

Other times insulation may be on the outside. Sometimes the insulation is inside the ductwork. Insulating hvac ductwork when insulating hvac ductwork use a foil faced fiberglass insulation with an r 6 or higher r value.