I'm not sure what kind of insulation to use on my duct work. Do I use fiberglass with the foil on one side or the stuff that slips over the duct work. It is 6" round ridged duct work. it looks like what ever was up there before had wire holding it up there instead of foil tape.
insulating duct work in attic
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First and foremost, seal all the seams with mastic or a proper tape.
Depending on the type and how much insulation you have in the attic, many times you can run it across the attic floor and blow loose insulation over top to a depth that will insulated the duct work at the same time.
Depending on the type and how much insulation you have in the attic, many times you can run it across the attic floor and blow loose insulation over top to a depth that will insulated the duct work at the same time.
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Either, or. Check the R-value rating as one may be more than the other. Even if you cover it with blown-in, add the important vapor barrier after wrapping to prevent condensation on/in the wrapped insulation while using the AC and the attic is hot/moist. They sell a fiber reinforced tape for hanging ducting (flex- though it won't cut/crush yours), check locally- code here requires R-7 through non-insulated spaces, more is better...
Gary
Gary
I was thinking about doing blow in without wrapping duct work, only thing is the duct work is about 12-18" about joists. I dont know the terminology but my furnace is in the garage and goes up through the ceiling so theres a square section in the attic that has all the duct work running from it. Anyway it isnt insulated either, what would I use for that?
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They make sleeves. Imperative to get the ductwork completely sealed prior to application.
You can actually take batts and wrap them around the ductwork as well for more R-Value but the pre-made sleeves are more user friendly for the initial insulation and vapor barrier.
http://www.handymanhowto.com/insulate-round-sheet-metal-air-duct/
You can actually take batts and wrap them around the ductwork as well for more R-Value but the pre-made sleeves are more user friendly for the initial insulation and vapor barrier.
http://www.handymanhowto.com/insulate-round-sheet-metal-air-duct/
I got up in the attic and noticed the gable vent on one end of the house is open and closed on the other end. Theres a lot of cold air blowing on to the uninsulated ducts. Can I close off the other gable vent for a couple weeks until I get some one to blow more insulation in? Theres basically none up there. There are vents in the soffit.
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No. Do not mess with the venting of the attic.
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