Insulating Air Conditioning Ducts In Attic

So logically the ducts deserve more not less insulation.

Insulating air conditioning ducts in attic.

Looking at the cooling side only the additional load would be. Other times insulation may be on the outside. Use the type of metallic foil duct tape recommended by the insulation manufacturer to seal and hold the insulation in place. When the attic is 20 f that insulation is addressing a delta t of 50 f.

Flexible ductwork comes with different insulation r values. You will need less material than you would for a rectangular or a square duct. This old paper faced insulation on hvac ductwork needs updating. I live in montreal and had a lennox air conditioner and ducts installed in the attic.

The condenser in your air conditioner works hard to get rid of heat and pressurize refrigerant for the return trip through your house. Fresh air ducts will focus on the fresh air in your air conditioning system. Here is a description of the phenomenon. What i ve observed attic temp 50c vent temp 21c attic temp 37c vent temp 18c attic temp 25c vent temp 13c not sure what the r value off flexible duct or main metal duct is.

Because the moving air is in the ductwork for only a short period of time it does not need the insulation r value the attic floor requires. Attic insulation keeps summer heat waiting proper attic insulation prevents summer s hot air from entering the house. Insulating hvac ductwork when insulating hvac ductwork use a foil faced fiberglass insulation with an r 6 or higher r value. After all most new homes have r 49 insulation on the attic floor holladay continues.

I was wondering is there any figures on the expected energy temp lose. 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. But the air in the ducts is facing a delta t of maybe 100 f or 120 f a greater delta t. Hot air tends to rise and an attic is the best place for hot summer air to creep inside your home and destabilize the efforts of your hvac in maintaining a cool temperature.

The attic duct is cold because cold air is flowing through it. The metal duct boot the fitting that holds the register or diffuser that is visible on your ceiling is also cold. How to insulate hvac ductwork today s homeowner. The air in your vented attic is hot and humid just like all outdoor air in florida.

Sometimes the insulation is inside the ductwork. R 8 duct insulation 5 227 btu hour. A round duct is the most effective. Find hvac duct fittings at lowe s today.

Imperial 4 in x 60 in galvanized steel round duct pipe. Imperial 6 in x 300 in insulated polyester flexible duct. For pricing and availability.