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White, powdery floor insulation–can you ID this?

davidmeiland | Posted in General Questions on

Picked up this image form another forum, and it might be a stumper. Who has the answer?

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  1. GBA Editor
    Martin Holladay | | #1

    I'm not convinced this is a stumper. It's hard to be sure from the photo, but that might simply be cellulose.

  2. stuccofirst | | #2

    blown fiberglass?

  3. user-1006269 | | #3

    My first thought was urea formaldehyde, but it looks a lot more like cellulose if you focus on what is on the rafters.
    If it is friable into dust, it is more likely urea.

  4. Peter_Rogers | | #4

    The grey stuff on the rafters does look like cellulose, but I've never seen cellulose maintain a horizontal structure like it appears to in some areas down below on the floor... anyone else see what I mean? Cellulose can certainly go in unevenly if installed poorly, but unless it's wet-sprayed I've never seen it do anything like that. I'm leaning towards UFFI.

  5. Peter_Rogers | | #5

    "White, powdery" also makes it sound like UFFI... but it really does look like cellulose... man, this is really bugging me.

  6. davidmeiland | | #6

    Here is the forum thread the photo comes from and it turns out there are more photos

    I have nothing to do with this situation, just a curious onlooker.

  7. GBA Editor
    Martin Holladay | | #7

    Sure looks like cellulose to me.


  8. Peter_Rogers | | #8

    the crawlspace is a total swamp... which explains the weird clumping I noted earlier.

  9. davidmeiland | | #9

    Nothing like a thread where the OP withholds all the really useful information until the end.

  10. Peter_Rogers | | #10

    hahaha, yeah, just cellulose.

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