A home’s duct work, though sometimes overlooked, is part of a critical system responsible for distributing air throughout the structure so that all rooms stay at a comfortable temperature. Properly sealing and insulating the ducts in your house, particularly where they pass through potentially unconditioned spaces like the attic or basement, is important for avoiding unnecessary energy loss and ensuring that the duct system serves its intended purpose well.
Wipe down the ducts so they are dust free, clean and dry.
Inspect the ducts carefully for any hole or sections which should be joined together but have split.
Fit the joints back together, if necessary, then cover the joints along with any holes with foil tape, butyl tape or a different heat-approved tape.
Measure the circumference of the duct and also the length of each part of duct if you’ll have to cut the insulation into smaller lengths to match it above the duct.
Lay out the duct wrap insulation and then trim it to match each measured section of duct. Also trim its width, if necessary, to make sure that it will fit snugly around the duct; take into consideration any overlapping taping or stapling seam incorporated into the insulating material.
Fit the prepared section or sections of duct wrap insulation above the duct, making sure it fits snugly. Using a small amount of tape to hold one aspect of the wrap in place could make it easier to match the remainder of the material above the duct, back to the point where it fills the taped side.
Staple the seams together or fasten the overlapping flap to the material under it. Use a outward clinch stapler along with the fasteners recommended or provided by the duct wrap insulation producer, or tape.
Tape over the seams with duct tape or a different heavy duty or heat-approved tape.