Insulating Metal Ductwork In Attic

Choose a faced fiberglass.

Insulating metal ductwork in attic.

The duct insulation should include a vapor barrier cover. Install ductwork so that it is in direct contact with i e laying on the ceiling and or truss lower cords. In this video this old house plumbing and heating expert richard trethewey helps a homeowner insulate his ductwork. Protect yourself from itchy fibers when working with fiberglass insulation.

If necessary switch the wires to reduce the blower to its lowest speed. Because the simplest and cheapest way to insulate an attic is to add material to the floor. The cost and effort to add more insulation is minimal. If your rigid metal ductwork has any insulation it may already have enough.

Although both the attic floor and the ductwork are insulated ted recognizes the situation isn t ideal. If it s uninsulated you should insulated it to at least r 4 to r 8 for dfw. How to insulate the attic air sealing the attic energy saving attic insulation duration. Mechanically fasten and mastic seal all duct connections.

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. Wrap metal duct tape around any seams you see in the ducts. Wear work gloves long sleeves and long. How to insulate sheet metal ac ducts 1.

Use metal flex or fiber board ducts that are insulated to code. Insulating hvac ductwork when insulating hvac ductwork use a foil faced fiberglass insulation with an r 6 or higher r value. Acute temperatures in these areas contribute to thermal loss in metal ductwork. Made from 1 to 2 inch thick sheets of rigid glass fiber and coated with an aluminum laminate for a moisture air barrier duct board comes in sections that fit together like metal ducts.

Make sure the foil surface of the insulation is free of dust before applying the tape. Consider adding more insulation as ductwork is farther from the furnace. But if the floor is covered in plywood you can t stuff enough insulation beneath it to do the job sufficiently not even in warm climates. A metal duct conveying cool conditioned air through a broiling attic in summer or warm air through a chilly crawl.

Press a continuous strip of foil tape to all longitudinal seams along straight runs of duct. Check the speed of the blower motor on the furnace. Go to the basement or crawl space of your home. Duct liner isn t generally a diy installation and if your ducts already have liner you don t need to insulate the exterior.

If you want to cover metal ductwork with blown in insulation t hese steps must be followed in this order. Use the type of metallic foil duct tape recommended by the insulation manufacturer to seal and hold the insulation in place.