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Anybody know what kind of blown-in insulation this is?

frasca | Posted in Energy Efficiency and Durability on

My attic floor was insulated with about 3-4 inches of this material, which I have never seen before. My first hypothesis based on weight and texture is finely shredded redwood bark, but I have never heard of that material’s being used as insulation. The attic was probably insulated between 1970 and 1995.

Does anybody know what this is?

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  1. user-2310254 | | #1

    It looks like wood fiber insulation. This link may be helpful:

    Note that apparently one manufacturer incorporated asbestos into its production process.

  2. frasca | | #2

    Thanks Steve!

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