Insulating Attic Heating Ducts

Insulating exposed heating ducts in attics basements and under subfloors can improve the energy efficiency of a heating system.

Insulating attic heating ducts.

Duct board much like the duct liner is also a fiberglass product. Use the type of metallic foil duct tape recommended by the insulation manufacturer to seal and hold the insulation in place. Read this before you start thinking about adding insulation to your attic. But the air in the ducts is facing a delta t of maybe 100 f or 120 f a greater delta t.

Proper insulation is a great place to start but it may not be enough to fully protect your home. If necessary switch the wires to reduce the blower to its lowest speed. After all most new homes have r 49 insulation on the attic floor holladay continues. Use metal flex or fiber board ducts that are insulated to code.

Don t use standard cloth duct tape on hvac ductwork since the adhesive won t hold up to extreme temperatures. Install ductwork so that it is in direct contact with i e laying on the ceiling and or truss lower cords. Duct liner isn t generally a diy installation and if your ducts already have liner you don t need to insulate the exterior. Purchase duct wrap insulation that complies with the 2009 international energy conservation code iecc standards that specify an r value of 8 for attic ducts and 6 for ducts located anywhere else.

According to the u s. For an added layer of protection you can apply duct mastic to the tape and duct. 911 attic insulation services 911 attic insulation helps keep your attic clean sanitary and properly insulated and vented. When hvac ducts are installed in a vented attic in a dry climate bury the ducts in attic insulation to protect them from temperature extremes in the unconditioned attic space.

Made from 1 to 2 inch thick sheets of rigid glass fiber and coated with an aluminum laminate for a moisture air barrier duct board comes in sections that fit together like metal ducts. When insulating hvac ductwork use a foil faced fiberglass insulation with an r 6 or higher r value. Insulation duct accessories the home depot store finder. In this video this old house plumbing and heating expert richard trethewey helps a homeowner insulate his ductwork.

The duct insulation should include a vapor barrier cover. When the attic is 20 f that insulation is addressing a delta t of 50 f. 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.

So logically the ducts deserve more not less insulation. Typical ducts install between a plenum or large supply duct and.