Best Way To Insulate Ductwork In Attic

Plan to pull up the flooring and layer new insulation on top of the old.

Best way to insulate ductwork in attic. 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. Bury the ducts deeply in insulation. That s what happened to the ducts in the lead photo of this article. Because the attic is hot it warms the surface of the duct board above the dew point temperature of the air in the attic.

Use a pressure sensitive vapor retarder tape designed for ductwork. Install loose fill insulation to cover the ducts and the attic floor to meet or exceed the code required r value for attic insulation. Get the right r value. If you then put a layer of insulation over this surface this same surface will now begin to cool down.

Add additional sealant if necessary. Most insulation relies upon the air space between its fibers to deliver the r value promised. Energy saver dealers 204 202 views. Avoid compressing the insulation.

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. Test total duct leakage. Let s use your existing duct board surface that now faces the attic as an example. In the southern california climate the recommended total attic insulation is a rating of up to r60.

How to insulate the attic air sealing the attic energy saving attic insulation duration. The duct insulation should include a vapor barrier cover. 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. Because the simplest and cheapest way to insulate an attic is to add material to the floor.

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. 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.