Air Ducts In Attic

The costliest are sheet metal ducts running in enclosed walls and ceilings.

Air ducts in attic. Use metal flex or fiber board ducts that are insulated to code. Steps to sealing attic air ducts locate the source of the thermal leaks by inspecting the ductwork while the air conditioner is running. When the attic is 20 f that insulation is addressing a delta t of 50 f. Type of ductwork system the least expensive duct system is a radial system of flexible ducts in an attic running to ceiling grates.

The duct insulation should include a vapor barrier cover. If you have central heating and or air conditioning in your home the warm or cool air is delivered to each room through a system of connected ducts and vents. If they are located in your attic be sure the area is properly insulated and any cracks or holes are sealed. Obviously it s hard to install r 60 duct insulation.

If you live in a consistently humid climate a dehumidifier can help keep the air around your ductwork dry. According to nrel researchers david roberts and jon winkler moving the ducts from a vented attic to a new location inside the conditioned space will reduce electricity used for cooling by 15 to 20 and will reduce the size of the needed air conditioning equipment by 0 5 to 1 ton. Make sure the duct is secure in place. Apply a generous amount of sealant mastic over the thermal leak.

These ducts are more cost effective good for tricky installations in tight places where rigid ducts. 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. If ducts are located in a crawlspace underneath your house cover the soil to reduce moisture. Ductwork running along an open ceiling in the basement of a one story home is also more affordable to replace.

Over time the insulation on the exterior of old metal ducts deteriorates letting the hot air come in contact with the very cold metal and this is worst when it comes to condensation. Choosing the right ductwork for installing in your attic hard ductwork. With hundreds of square feet of ductwork surface area in the attic and a δt of 75 f the air coming out of the vents in your home will be significantly higher than 55 f. So logically the ducts deserve more not less insulation.

This type of duct means a smoother interior with better air flow insulation applied on the outside to. The really bad news is that with old metal duct systems the only option is replacement of the ducts to stop the rain in the attic. But the air in the ducts is facing a delta t of maybe 100 f or 120 f a greater delta t. The air ducts for a central hvac systems are typically located above a home in the attic or upper crawl space or underneath a home in the space between the foundation and the floor so you don t see them unless you have cause to replace them.

Install ductwork so that it is in direct contact with i e laying on the ceiling and or truss lower cords.