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Do you recognize this insulation?

vap0rtranz | Posted in Green Products and Materials on

Recognize this insulation? 

There are 2 types I’ve found.  Is the one covering the attic floor look like blow in cellulose?  or vermiculite?  And the one that’s like a sandwhich between the roof rafters some kind of old house wrap?  That one is wrapped in a kind of tar paper …

Neither are sparkly or shiney, though perhaps that is due to all the dust.  It is very fluffy.

Crawling through our knee wall attics in a Cape Cod built sometime between 20’s & 40’s, I bumped into these and wonder if a previous owner did a deeper weatherization or efficiency program that a home auditor had assumed…  I’ve also found typical “pink” fiberglass batts and Tyvek but this stuff looks much older.  Also found no signs of air sealing (no caulk/sealant, batts that are darker colored, etc.) though there is black tar paper over the board sheathing on exterior walls.

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Replies

  1. Indiana Guy | | #1

    I'm no expert so take it with a grain of salt.

    First two pics look like it's cellulose.
    The third pic looks like it's old fiberglass.

    Although, it might be better if you took close up shots of the cellulose.

  2. Expert Member
    Zephyr7 | | #2

    It looks like old cellulose to me too. Old blown in fiberglass was usually yellowish or pinkish, unless it’s REALLY dirty.

    Vermiculite would have some shiny/sparkly flakes in it. I’m pretty sure that’s not what you have in those pics.

    Bill

  3. GBA Editor
    Peter Yost | | #3

    I agree regarding the first two photos; the third photo is simply too dark to tell much of anything.

    In terms of what vermiculite insulation looks like, see this GBA blog: https://www.greenbuildingadvisor.com/article/fixing-attics-with-vermiculite-insulation.

    Peter

  4. vap0rtranz | | #4

    Thx Peter, Bill, and Indiana Guy. A contractor confirmed that the blown-in stuff was cellulose.

    The dark pic is a poor camera, but the same contractor thought it to be old "batt" that was faced on all sides, like a sandwhich, that was evidently put inbetween roof rafters and wall stud bays but has become compressed over time (the dark pic is from a roof rafter).

    1. Expert Member
      Dana Dorsett | | #5

      >"The dark pic is a poor camera, but the same contractor thought it to be old "batt" that was faced on all sides, like a sandwhich, that was evidently put inbetween roof rafters and wall stud bays but has become compressed over time (the dark pic is from a roof rafter)."

      In the 1920s there were thin/very thin horse hair batts with kraft (asphalted or not) on both sides. If you burn some of the fiber in the middle your nose might be able to verify if it was one of those products. (My 1920s vintage house had half-inch horse hair with kraft on both sides in the walls.)

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