Apply a long strip of foil tape along the seam in the insulation.
Best insulation for attic ductwork.
Duct liner isn t generally a diy installation and if your ducts already have liner you don t need to insulate the exterior.
The attic ductwork is flex duct work.
Wrap the insulation around the duct and then pinch the seam closed.
For an added layer of protection you can apply duct mastic to the tape and duct.
Close to 25 of the energy you use to heat and cool your home disappears through leaky ductwork.
The department of energy claims that the average us home loses hundreds of dollars a year in heating and cooling costs.
The fiberglass duct board is by far the most effective.
You don t want to end up with the wrong type of insulation for your air ducts.
Secure the insulation with short strips of foil tape.
To install preformed duct insulation start by disconnecting an elbow to expose the end of the duct.
Granted the insulation on that duct has surpassed it life expectancy and my duct resides in the unconditioned attic.
Each job may require a different form of insulation.
Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.
Use the type of metallic foil duct tape recommended by the insulation manufacturer to seal and hold the insulation in place.
I called out the original hvac company and they took a look and said they saw no water.
You can find formaldehyde free insulation that also has an acrylic coating.
Duct board much like the duct liner is also a fiberglass product.
Find your zone on the map and then use the chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces.
Repeat to insulate the remaining ducts.
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.
These ducts are usually made out of thin sheet of metal that easily conduct heat.
When insulating hvac ductwork use a foil faced fiberglass insulation with an r 6 or higher r value.
It was new when the ac was put in 7 years ago.
Insulate ducts located on roofs and on unconditioned spaces like the attic garage crawlspace or unfinished basement.
The ducting currently rests on the attic joist which causes any residual r value from disintegrating insulation to be non existent.
Table 1 shows effective r values for 8 inch round ducts at three attic insulation levels and three duct insulation levels r 4 2 r 6 and r 8.
The effective r value of a buried duct installation depends on the size of the ducts the r value of the duct insulation and the depth of the loose fill insulation.