Best Way To Insulate Ductwork In Attic

Get the right r value.

Best way to insulate ductwork in attic.

Tape any punctures in the insulation s vapor barrier to prevent leaks. That s what happened to the ducts in the lead photo of this article. In last week s blog i discussed the practice of burying attic ducts in deep insulation since burying ducts is simply one of several ways to address the energy waste associated with the decision to locate ducts in a vented unconditioned attic it s worth taking a fresh look at all of the possible solutions to the attic duct problem. Air sealing all the ducts and air handler connections and seams and air sealing all the duct boots to the ceiling gypsum and any other penetrations is a critical first step prior to adding any insulation.

If you then put a layer of insulation over this surface this same surface will now begin to cool down. This isn t equivalent to bringing them into the conditioned space as you ll still have additional duct load but it s a lot better than having them in unconditioned attic space. Add additional sealant if necessary. The duct insulation should include a vapor barrier cover.

Test total duct leakage. Install loose fill insulation to cover the ducts and the attic floor to meet or exceed the code required r value for attic insulation. Most insulation relies upon the air space between its fibers to deliver the r value promised. Avoid compressing the insulation.

Bury the ducts deeply in insulation. The higher the r value the more resistant it is to heat flow the more efficient it is and the more you will save on heating and air conditioning costs. Because the simplest and cheapest way to insulate an attic is to add material to the floor. 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.

Because the attic is hot it warms the surface of the duct board above the dew point temperature of the air in the attic. How to insulate the attic air sealing the attic energy saving attic insulation duration. Energy saver dealers 204 202 views. Mechanically fasten and mastic seal all duct connections.

Use a pressure sensitive vapor retarder tape designed for ductwork. Let s use your existing duct board surface that now faces the attic as an example.