How To Insulate Ductwork In Attic

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

How to insulate ductwork in attic.

The duct insulation should include a vapor barrier cover. Recently i had another hvac company come out and put in a new bathroom vent and they told me they believed the duct work was full of water. Check the speed of the blower motor on the furnace. Bury the ducts deeply in insulation.

If necessary switch the wires to reduce the blower to its lowest speed. Press a continuous strip of foil tape to all longitudinal seams along straight runs of duct. Most insulation relies upon the air space between its fibers to deliver the r value promised. The attic and walls are one of the most important areas to insulate in any space.

That s what happened to the ducts in the lead photo of this article. Mechanically fasten and mastic seal all duct connections. When these ducts are exposed to exterior air the plastic jacket never gets cold enough to permit condensation because the hot attic air keeps the plastic jacket warm. Plan to pull up the flooring and layer new insulation on top of the old.

Install ductwork so that it is in direct contact with i e laying on the ceiling and or truss lower cords. Because the simplest and cheapest way to insulate an attic is to add material to the floor. Energy saver dealers 204 202 views. Avoid compressing the insulation.

Most attic ducts are insulated flex ducts that is flex ducts with r 6 or r 8 fiberglass insulation along with an exterior polyethylene jacket. It was new when the ac was put in 7 years ago. Use a paintbrush to apply duct mastic to the joints where an elbow connects to a duct. But what about the parts behind the walls and in the ceiling.

Tape any punctures in the insulation s vapor barrier to prevent leaks. How to insulate the attic air sealing the attic energy saving attic insulation duration. Use metal flex or fiber board ducts that are insulated to code. Use a pressure sensitive vapor retarder tape designed for ductwork.

Cover the metal ductwork with closed cell spray foam. The foam provides a vapor barrier so the ductwork won t sweat. The attic ductwork is flex duct work. 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.

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.