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Community and Q&A

Insulating ducts

jcastilow | Posted in Energy Efficiency and Durability on

I’m looking to insulate the ducts in my crawlspace to R8.0.

At my local Lowe’s and Home Depot, I don’t really see any insulation sleeves – only one or two stores carry these sleeves and not with the R-value I want.

I’ve heard that the inner diameter of flex duct is slightly larger than galvanized duct and can be used to insulate rigid duct. Is this true? If so is it a good idea?

I live in Dayton, OH. I’ve looked for an HVAC supply store, but google hasn’t turned up much that looks promising. I’m a newbie, sorry for any unclear nomenclature or misunderstandings. Thanks for any help,

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  1. GBA Editor
    Martin Holladay | | #1

    I think what you want to ask for is duct insulation (sometimes called duct wrap), not "insulation sleeves."

    Owens Corning makes R-8 duct wrap:

    If this product isn't stocked at Home Depot or Lowe's, perhaps they can order it for you.

  2. jcastilow | | #2

    Hi Martin,

    Thanks for the answer, but I mean insulation sleeve. As seen here:

    To me it makes sense that they can make a sleeve for flex duct why not for rigid duct? I like the idea that there are much fewer/smaller joints and much less taping (probably less waste and less cutting too).

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