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Community and Q&A

Cellulose insulation settling

michaeldrehl | Posted in General Questions on

I wanted to insulate my uninsulated kitchen walls with cellulose. The walls were lath and plaster long ago but sheetrock was installed on top of it with quarter inch beams on plaster.
If I drill a hole on top so I cut through the sheetrock and plaster and pour in cellulose from above and let it settle for a couple of weeks, and fill some more cellulose on the top where it settled, will it achieve a good density to not grow any mold or any other issues with loose filling?

Thanks for your answer.

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  1. Expert Member
    Dana Dorsett | | #1

    Cellulose isn't sold in a form that allows loose filling. It comes in compressed bags of material that have to be broken up and fluffed-out with high velocity air by the insulation blower. Even tumbling along the hose and it's length are a necessary part of the process of taking the compacted cellulose flake and separating it into individual tiny flakes of paper.

    Some types of rock wool can be loose poured, but it's really designed to be mixed up and fluffed out in a blower for low density open blowing.

    Perlite designed for insulating CMU block cores can also be loose poured into framed wall cavites.

  2. GBA Editor
    Martin Holladay | | #2

    You can usually borrow a cellulose blower from a Big Box store, and with a little practice, you can get close to achieving a dense-pack installation with this type of blower.

    For more information, see this article (and the comments that follow the article): "Borrowing a Cellulose Blower From a Big Box Store."

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