Vermiculite insulation home page:
Vermiculite identification photos, hazards, history, advice: what is vermiculite insulation, how is it identified, & what should be done about potential vermiculite-asbestos hazards ascribed to Zonolite ZAI attic insulation?
This article series explains how to recognize vermiculite building insulation that may contain asbestos fibers.
We provide photographs and descriptive text of asbestos insulation and other asbestos-containing products to permit identification of definite, probable, or possible asbestos materials in buildings.
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?
This article permits visual identification of vermiculite insulation; we include our own as well as US EPA photographs of various forms of vermiculite insulation to assist in recognizing vermiculite in buildings.
We describe the history of vermiculite insulation, the asbestos hazard that may be present depending on which vermiculite insulation product is present, and how asbestos is identified in vermiculite insulation.
We give the history of the Libby vermiculite mine, its purchase by WR Grace Corporation, the asbestos-related bankruptcy filing, asbestos abatement cost claims & filings & the current ZAI settlement trust that may assist building tenants or owners with vermiculite removal costs.
We also list other, including current producers of vermiculite insulation.
This document assists building buyers, owners or inspectors who need to identify asbestos materials (or probable-asbestos) in buildings by simple visual inspection.
Watch out: vermiculite from some sources contains asbestos and can be an asbestos dust hazard in buildings. Details about the asbestos content in some vermiculite insulation products is found in this article.
[Click to enlarge any image]
Vermiculite is a mineral (hydrated laminar magnesium-aluminum-iron silicates or hydrated phlogopite or biotite mica) from the phyllosilicate group. Vermiculite looks somewhat like mica in that it includes shiny flat plates of material that can be separated.
Vermiculite has a wide range of uses in industry, construction, packaging, insulation, packaging, even animal feed.
Building owners of older structures that had little or no attic insulation are most-often familiar with vermiculite that was poured into attic floors as a loose-fill insulating product.
In some buildings vermiculite may also have been blown into previously-uninsulated wall cavities.
See VERMICULITE LOOSE FILL Attic Insulation May Go Unrecognized as a Potential Hazard
In addition to its use as an insulation product and in construction as a masonry fill, a cavity fill, & in concrete blocks, vermiculite is added to soils in horticultural applications and to cement to make a lightweight concrete swimming pool base.
In contemporary building construction (2016) vermiculite is used in lightweight concrete and it has been widely used in spray-applied fireproofing. Spray-on fireproofing takes advantage of the light-weight and fireproof properties of vermiculite.
Older spray fireproofing that also used vermiculite may have employed Libby Amphibole Asbestos (LAA) from the Libby Montana mine: a vermiculite source that contained asbestos in several forms that we list later in this article.
After 1991 spray-applied fireproofing that uses vermiculite would not be expected to use Libby-Montana vermiculite, so it would not be expected to be contaminated with asbestos. Pure vermiculite would not contain asbestos.
Vermiculite is also used in special applications such as industrial filters [17], in ceramics (ground & exfoliated, bonded with calcium silicate to form an unfired insulating layer), as a heat resistant component in brake linings (Yun 2010) and even as a treatment for oil-contaminated waters (Mysore 2005) and as a dessicant (>Spitze 1942).
And as we illustrate below, vermiculite insulation can show up as an insulating layer in many products such as a ceiling light fixture.
Details about the properties of vermiculite are
Also see ASBESTOS STYROFOAM PANELS where we discuss WR Grace / Zonolite Styrofoam panels that were sometimes combined with asbestos materials.
These photographs by David Grudinski illustrate a potential asbestos hazard that merits further investigation.
Loose-fill vermiculite from the attic of this home was found falling through a ceiling opening into the occupied space below.
A cursory inspection of the attic showed fiberglass insulation in the attic floor. The vermiculite was below the fiberglass.
We cannot assert that this is an asbestos hazard but it might be. Common-sense advice would include:
Home inspector David Grudzinski provided more vermiculite insulation photographs now found
at VERMICULITE LOOSE FILL Attic Insulation May Go Unrecognized as a Potential Hazard
These photos illustrate another home in Rhode Island with Vermiculite. A 1952 Colonial in North Smithfield RI. I tend to find Vermiculite in older homes of the older less developed towns on the outskirts of the state. In this case, Vermiculite was filled in the rafter bays after "Beaver board" was nailed to the underside of the rafters.
In this home, the homeowner was unaware, and the realtors had no knowledge of the issue.
Recent renovations to the home have caused the Vermiculite to be disturbed and the product is spilling out of the home. The bath fan is adding further potential contamination by blowing the product around in the attic.
I took the time to explain the concerns to the buyer and shared the information about the Zonolite Trust which offers grants for mitigation.
Watch out: As many are unaware, testing for Asbestos under PLM has proven unreliable with Vermiculite. The fibers are too random among the mass of vermiculite in the homes.
The Zonolite Trust has been testing for Barium as a marker to confirm the product in fact was mined at the Grace mine in LIbbey . - David Grudzinski, cited above.
Our vermiculite insulation photo (left) from the attic of a home in New York state, shows how you might spot the presence of vermiculite insulation even when most of the attic floor has been covered-over. You'll also notice that while most of the vermiculite insulation particles in this photograph are silver-tan or silver gray, some dark fragments are also present, as well as incidental debris.
No.
Libby Amphibole Asbestos mined at the Libby Montana site until 1990 was formed in the Triassic period (225 million years ago) and contained tremolite asbestos as well as other forms of asbestos including winchite and richerite, two forms of fibrous amphiboles.
See ZONOLITE BRAND VERMIULITE INSULATION ZAI & CLAIMS
Most of the vermiculite in the currently operating vermiculite mines (listed below) was formed 1.5 to 3 billion years ago in the pre-Cambrian and Archaen periods.
See this VERMICULITE MSDS from Schundler[17]
While an expert lab test using polarized light microscopy may be needed to identify the specific type of asbestos fiber, or to identify the presence of asbestos in air or dust samples, many asbestos-containing building products not only are obvious and easy to recognize, but since there were not other look-alike products that were not asbestos, a visual identification of this material can be virtually a certainty in many cases.
Also see ASBESTOS DUCTS, HVAC a field identification guide to visual detection of asbestos in and on heating and cooling system ducts and flue vents.
Also see Micro-Photographs of Dust from the World Trade Center collapse following the 9/11/01 attack. Links to U.S. government and other authoritative research and advice are included.
Walter C. McCrone, at McCrone Research Institute published detailed procedures for identifying asbestos by microscopic examination, and identifying which type of asbestos is in a material.
His text and microscopy courses taught at McCrone Research and subsequently at McCrone Institute provided methods for identifying fibrous and non-fibrous asbestos in a wide range of materials.[12]
Dr. McCrone's photograph of fibrous tremolite asbestos is illustrated at above left. Like many minerals and some other particles, asbestos, including tremolite asbestos, can occur in both fibrous (above left) and non-fibrous (below left) forms.
Vermiculite mining operations are found world-wide but the largest currently operating vermiculite mining operations continue in
Shown here: a plastic bag used to package Zonolite Attic Insulatin - Vermiculite insulation that is treated as presumed to contain asbestos; photo courtesy of InspectApedia reader Candace Morais (2023/12/27) and posted originally
at VERMICULITE HISTORY & PROPERTIES [Click to enlarge any image]
to HOW TO IDENTIFY VERMICULITE INSULATION - separate article
Watch out: while it is certainly possible to identify a material as vermiculite or vermiculite insulation by examining it with the naked eye or by examining photographs such as those on this page, one cannot determine whether or not vermiculite contains asbestos simply by looking at it with the naked eye nor by comparing photographs of the insulating material.
To absolutely identify asbestos content in vermiculite microscopic examination using polarized light (PLM) is necessary.
See ASBESTOS TESTING LAB LIST if you need to have an insulation sample tested for asbestos.
Moved to VERMICULITE IDENTIFICATION PHOTOGRAPHS
Watch out: vermiculite insulation was not only poured into attic floors but also into building wall cavities during insulation retrofit projects.
Particularly in older balloon-framed buildings, vermiculite could be poured from the attic right into wall cavities extending all the way to the building foundation top. Vermiculite was also often poured into hollow-core concrete block walls.
Moved to MUNN & STEELE VERMICULITE, MICA-FIL, Siscoe Vermiculite Mine
See UNIDENTIFIED (BRAND) VERMICULITE PHOTOGRAPHS
Moved to VERMICULITE IDENTIFICATION PHOTOGRAPHS (more)
This topic is now
at VERMICULITE INSULATION INCIDENTAL EXPOSURE HAZARDS ?
Uses of vermiculite were explored as early as 1824 by Webb, appearing the very next year in Robinson's catalog of American minerals. (Robinson 1825).
Please see details about the history of vermiculite
at HISTORY of the DISCOVERY & CHARACTERIZATION of VERMICULITE.
Moved to a new article at VERMICULITE PROPERTIES
This topic has been moved.
See WHAT TO DO ABOUT VERMICULITE INSULATION
The best way to minimize your risk of amphibole asbestos exposure is to avoid disturbing vermiculite-based insulation in any way. If vermiculite-based insulation is contained and not exposed to the home or interior environment, it poses very little risk.
This discussion has moved to
ZONOLITE BRAND VERMICULITE INSULATION
Watch out: Depending on the mine from which this mineral-based insulation was obtained, vermiculite insulation may contain asbestos fibers (including tremolite asbestos) and could present a hazard in buildings, especially if disturbed during renovations.
As we discuss at our notes on other loose-fill insulations such as mineral wool or cellulose, any building insulated with loose-fill or spray-in insulation may benefit from the ability of these loose materials to fill gaps and openings more uniformly than might be found if sloppy workers are careless about installing insulating batts.
...
Below you will find questions and answers previously posted on this page at its page bottom reader comment box.
Reader comment/question: Your website is terrific and very helpful. I was on there to try to identify something. We removed a front hall lamp, by the entrance, and found some wood like droppings inside the lamp. Please see attached photos.
We are not sure what this is but are concerned that it could be dry wood termite droppings. Any ideas? - Anonymous by private email, 2016/09/19
Reply:
What your photos show looks very much like vermiculite insulation -
Anon said:
I will send you a photo of the light fixture when I return home (just writing from the office). The house was built in 1934 (plaster walls, etc.). The light fixture looks something like this (picture from the internet):
Mod said:
OK now I understand: that ceiling light fixture is insulating its heat from the ceiling above, perhaps for added fire safety. I look forward to seeing actual photos and with your OK will add this info to our vermiculite and light fixture articles as that will help other readers.
Beware that some vermiculite contains asbestos - avoid making a dusty mess and use damp wiping not a household vacuum cleaner for any spill cleanup.
Anon said:
Would you suggest we have the vermiculite tested for asbestos? We kept a sample.
Mod said:
No. The volume of such a small amount of insulation and thus the hazard are rather small. It wouldn't change what you do.
On 2021-03-21 by Rob - does this look like vermiculite?
I found this taking off ceiling in an old house thoughts? Just stuff on top of the square ceiling tile. Thought it was mouse stuff but researching.. may not be thks
On 2021-03-22 by (mod)
@Rob, that looks like vermiculite insulation
On 2021-02-02 by coleman - is this Sears Homart Insulation Vermiculite?
I can't find ANY information on vermiculite from Homart and Sears (best of all insulation) I found 2 bags in my attic and will be sending it out for a test but was trying to find some product info in the meantime. I'm attaching pics if anyone has information it would be greatly appreciated
Here is the Sears best of all insulation bag [ shown above ]
On 2021-02-02 by (mod) - don't confuse mineral wool or rock wool with vermiculite insulation
Coleman, thank you for the photos of Sears Best "Mineral Fill" insulation, and your photo of Sears Homart Pellet Type Rock Wool Insulation - we will certainly keep these with this article series.
Typically national brands like Sears contracted to buy their materials from more than one supplier, depending on availability and price; so it is possible that **IF** you have vermiculite insulation sold by Sears, that least some Sears vermiculite came from the Libby mine; until I can find more specific details it would be prudent to treat the Sears Vermiculite as presumed to contain asbestos.Really? Well not quite. Both of your packages describe insulation that may not be vermiculite at all but rather mineral wool or rock wool.
Certainly the Sears Pellet Type Rock Wool is likely to be mineral wool not vermiculite, and
Your Sears Roebuck Best of All Insulation package labeling describes the product as "Mineral Fill" - that may be mineral wool, too.
Please post a photo of what the actual insulation itself looks like so that we can confirm what it is.
Rock Wool or mineral wool insulation is not a vermiculite product.
See details at MINERAL WOOL APPEARANCE VARIATIONS
On 2020-03-12 by Anon - ever seen vermiculite insulation in a cathedral ceiling ?
Hi.
I have a 1960 house. Have you ever seen vermiculite insulation in a cathedral ceiling ?
On 2020-03-13 - by (mod) -
Anon
Vermiculite in a cathedral ceiling is possible, though certainly not a first choice as it's a bit difficult to install there.
On 2019-03-26 by joe m. - worried that I may have been exposed to asbertos - white stuff in a box
i found a box in back of my cluttered closet that i keep my every day clothes in the box i found a metal iron rest with a caulky white material some pieces were damaged from age but in a panic i put in a plastic bag and put it outside.
i put on a respirator mask wet down the closet with spray bottle of soap and water washed all of my cloths, and wiped down boxes and bags mopped the whole house with disposable pads.
This was 6 months ago but i am still worried that i exposed myself to abestos.and i wii get sick. Help in panic mode Thank you
On 2019-03-27 - by (mod) -
Joe
I can't assert from your note that your box contained asbestos materials but surely if you cleaned up as you described your response was reasonable. If you're still worried you might collect a representative sample or two of settled dust from your living area to have tested by a certified asbestos test lab - check the page top EXPERTS DIRECTORY
On 2019-01-11 by Ann Markley - Johns- Manville Spintex "Blown" Home Insulation - vermiculite?
I see no mention of Johns- Manville Spintex "Blown" Home Insulation. Does it contain asbestos? It was a vermiculite looking material that was blown into wall spaces in the 1950's in Pennsylvania.
On 2019-01-11 by (mod) - Mansville SpinTex is not vermiculite
Ann:
SpinTex is mineral wool, not vermiculite, that's why we didn't discuss it in this article.
Take a look at
MINERAL WOOL - ROCK WOOL INSULATION
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