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Please help ID this loose-fill insulation

ohioandy | Posted in General Questions on

Recently did some work in an attic that contained a type of loose-fill insulation I’ve never seen before, and I would like to help the homeowner find out what it is. It does not look like vermiculite.

It’s been poured over old fiberglass batts in this 1940’s-era house; I’d guess sometime between the 1950’s and 1970’s. It looks for all the world like EPS beads. Lily white, about the size of peas, very consistent in size. But it sure ain’t EPS. It feels like lightweight little rocks, and just disturbing it a little kicks up the most obnoxious dust.

All the vermiculite I’ve seen is distinctive enough: darker colors, mica-shine, angular shapes of varying size. This is not that.

Of course, I’ll tell him to get a professional opinion and lab test, but was hoping to provide some links to justify the expense in our wild west, unregulated corner of Ohio.

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  1. GBA Editor
    Martin Holladay | | #1



  2. ohioandy | | #2

    Martin, that sure looks like it. Perlite didn't come up on any of my "loose-fill" google searches. So I see that this "wonderful volcanic popcorn," as Popular Mechanics calls it in 1954, is quite benign. At least it doesn't seem to harbor asbestos, but lordy is the dust terrible in the throat. Apparently classified as a nuisance or inert dust. Perlite Institute: "There are no published reports of adverse health effects from exposure to Perlite dust." Even acceptable for food contact according to USDA. Egads.

  3. user-757117 | | #3

    If its that dusty you might want to recommend some precautions in any case.
    Diatomaceous earth (DE) is also "food safe" and I know plenty of people who don't think twice about climbing into their chicken coops and breathing it in while they broadcast it all over.
    But the dust is hard on your lungs - maybe not as bad as asbestos but still like little knives to lung tissue.

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