Insulated Ductwork For Attic

The shiny vapor barrier will protect the ductwork from sweating as long as it s exposed to the surrounding air.

Insulated ductwork for attic.

Today s flexible ductwork is covered with a shiny metallic cover this is its vapor barrier. 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. Check the speed of the blower motor on the furnace. Although both the attic floor and the ductwork are insulated ted recognizes the situation isn t ideal.

The duct insulation should include a vapor barrier cover. If necessary switch the wires to reduce the blower to its lowest speed. Unfortunately so many houses especially newer homes end up with ductwork running through the attic. Summer hasn t even arrived he notes in a post at gba s q a forum and when the temperature outside climbs to more than 95 f the temperature in the attic tops 120 f.

When these ducts are exposed to exterior air the plastic jacket never gets cold enough to permit condensation because the hot attic air keeps the plastic jacket warm. Install ductwork so that it is in direct contact with i e laying on the ceiling and or truss lower cords. Is it ok to do it. First consider the duct location.

Hvac ductwork is typically visible in your attic especially flexible ductwork. The greater the temperature extreme between the air inside the duct and the air surrounding the ductwork the greater your need for duct insulation. Press a continuous strip of foil tape to all longitudinal seams along straight runs of duct. Covering ductwork with insulation.