Covering Flex Duct With Insulation

In the example given for the best results we recommend first insulating the lower surface of the duct then the side walls and lastly the top.

Covering flex duct with insulation.

Pull insulation and outer liner over the joint and seal to the attached duct or boot with mastic or foil tape figure 5. The best way to address poorly insulated attic ducts is to replace older flex duct with newer flex duct with a higher r value at least r 8. The duct insulation should include a vapor barrier cover. Seal all duct joints with foil faced duct tape.

Add additional sealant if necessary. Install loose fill insulation to cover the ducts and the attic floor to meet or exceed the code required r value for attic insulation. Apply k flex contact adhesive to the insulation surface and to the duct surface. Duct insulation sheets typically used as duct wrap these flexible sheets consist of polyethylene bubbles covered with aluminum polyester foil that prevent 96 of heat from radiating into or away from duct.

Installing contractors prefer it for many reasons including improved handling easier cutting and less dust. If you need to bury the ducts in insulation the only safe way to do it is to first install a 2 inch layer of closed cell spray foam on the outside of the ducts. Ecotouch insulation for flexible duct owens corning ecotouch insulation for flexible duct is a lightweight flexible resilient thermal and acoustical insulation made of inorganic glass fibers bonded with a thermosetting resin. Our duct wrap is available in a variety of densities thicknesses and with or without facings.

The foam provides a vapor barrier so the ductwork won t sweat. Use on rectangular and round ductwork. Download brochure pdf v 1540886844000 6 23 mb. How to cover round air ducts with insulation 1.

To attach flex duct pull back the outer liner fasten the inner liner over the collar with a tool tightened tension tie and mastic seal the connection. If it s uninsulated you should insulated it to at least r 4 to r 8 for dfw. The cost and effort to add more insulation is minimal. Cover the spray foam with fire retardant spray.

Mechanically fasten and mastic seal all duct connections. Cut a second length of standard insulation batt to the length of the horizontal duct to cover the duct s underside. If there is damage to the metal or flex pipe duct repair it first. Cover the metal ductwork with closed cell spray foam.

This will prevent the penetration of humidity. In some cases the insulation is flex board which itself is the pipe or duct. 2 cut a piece of foil tape large enough to cover. Test total duct leakage.

If you want to cover metal ductwork with blown in insulation t hese steps must be followed in this order.