Insulate Heat Ducts In Attic

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.

Insulate heat ducts in attic.

She asked me to go into the attic to find the roof leaks or where the snow is blowing in through the soffits. Use the type of metallic foil duct tape recommended by the insulation manufacturer to seal and hold the insulation in place. To insulate the exterior you have a choice between sleeve style insulation and blanket wraps which literally wrap around the ductwork. The rigid insulation was saturated from condensation.

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. R 8 duct insulation 5 227 btu hour. Plan to pull up the flooring and layer new insulation on top of the old. Hvac ductwork is typically visible in your attic especially flexible ductwork.

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. Use a paintbrush to apply duct mastic to the joints where an elbow. To install sleeves you must either disassemble the ductwork and slide it on before reassembling the ducts or as many homeowners find themselves doing slit it and wrap it around like the blanket style material. Look for signs of air leaks at seams or joints such as streams of dust.

How to insulate your central air heating ducts 1. Purchase duct wrap insulation that complies with the 2009 international energy conservation code iecc standards. 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. Inspect the span of ductwork to be insulated.

Today s flexible ductwork is covered with a shiny metallic cover this is its vapor barrier. When insulating hvac ductwork use a foil faced fiberglass insulation with an r 6 or higher r value. The shiny vapor barrier will protect the ductwork from sweating as long as it s exposed to the surrounding air. According to rightsuite the software we use the supply ducts have about 560 square feet of surface area and the return ducts 101 square feet.

Because the simplest and cheapest way to insulate an attic is to add material to the floor. If necessary switch the wires to reduce the blower to its lowest. Press a continuous strip of foil tape to all longitudinal seams along straight runs of duct. Check the speed of the blower motor on the furnace.

Make sure the foil surface of the insulation is free of dust before applying the tape. Install ductwork so that it is in direct contact with i e laying on the ceiling and or truss lower cords.