Insulate A C Ducts On Roof

The existing metal ductwork in an older home may or may not have insulation.

Insulate a c ducts on roof.

This will be a continuous procedure that will look. It should significantly reduce the heat transfer from the ductwork to the attic and reduce the supply temps entering the home and reduce the amount of attic air that get sucked into the home. Make sure the foil surface of the insulation is free of dust before applying the tape. I found instead a vintage 3 ton ac unit with 1 rigid insulation taped all over it and insulated flex duct snaking all over the poorly insulated attic.

To fit your ducts simply cut the sleeve to length with a. Duct temp gain when inside doghouse with r30 is less than 5 at 50. Come in pre measured lengths. Free online duct insulation cost guide breaks down fair prices in your area.

You can cover metal ductwork with blown in insulation if you take two steps first. Use the type of metallic foil duct tape recommended by the insulation manufacturer to seal and hold the insulation in place. Get 2020 duct insulation price options and installation cost ranges. Input project size product quality and labor type to get duct insulation material pricing and installation cost estimates.

Insulating hvac ductwork when insulating hvac ductwork use a foil faced fiberglass insulation with an r 6 or higher r value. The absolute best way to run the ductwork above the roof is to use r8 insulation on the ductwork internal and build a doghouse outside the ductwork with minimum r30 insulation on sides and top of duct. The flex ducts were literally filled shut with ice in the low spots compressing the scant insulation layer beneath them. Now if you pull off the old 4 2 insulation and seal all joints and seams in the metal ductowrk underneath with duct approved mastic then reinsulate the ductwork with r 8 0 foil backed duct wrap you will see the greatest improvement your ductwork system is capable of.

While insulating the interior of the ac ducts is more time and labor intensive it could yield a greater level of energy and savings on your monthly cooling bills. Common sleeve materials include foam bubble wrap and fiberglass all typically featuring a foil like outer surface to provide air and moisture resistance. 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. Wrap the insulation around the pipe overlapping each seam by one inch.

They may have an adhesive strip to make the installation a little easier. The rigid insulation was saturated from condensation. Apply a long strip of foil tape along the seam in the insulation. Install the rolled duct insulation by beginning at an end of a round pipe.

Secure the insulation with short strips of foil tape.