FAQs About Vermiculite


Q. What is Vermiculite and is all Vermiculite harmful?

 Vermiculite is a naturally occurring mineral (basically, it's a rock) that has the unusual property of expanding into accordion shaped pieces when heated. The expanded vermiculite is a light weight, fire-resistant, absorbent, and odorless material. These properties allow vermiculite to be used in a wide variety of products, most notably as attic insulation.  Surprisingly, Vermiculite is still sold in stores today.  However, the vermiculite we may purchase at the local nursery as a soil conditioner is tested frequently and does not contain asbestos.   Look to this website for clarification:  www.vermiculite.org   

The main concern is with a particular vermiculite ore that originated from a certain mine(s) in Libby, Montana.  Unfortunately this ore had asbestos amphibole fibers mixed within it and was processed, bagged and installed in millions of homes throughout the world.   Estimates conclude that approximately 75 to 80% of the vermiculite installed in attics, up until the mid 1990's, originated from this location.   The most common brand name for the vermiculite that originated from this mine was a product named "Zonolite".   


Q. How Do I Know If I Have Vermiculite Insulation?


 Vermiculite attic insulation is a pebble-like, pour-in substance that is usually light-brown or gold in color. For pictures of the material click HERE.  If you are not sure whether you have vermiculite in your attic please call us to arrange for an inspection.   Vermiculite is not always easy to see.  Often, other forms of insulation may have been installed over the vermiculite.  Unfortunately, the only way to be sure is to enter the space and physically lift or dig into existing insulation.  We highly recommend donning proper respiratory protection while looking for vermiculite in the confined spaces attics present.  In many instances vermiculite may have fallen into wall cavities or pipe chases and can be seen in lower areas of a dwelling.  Following plumbing/chimney chases, looking at lighting fixtures and up on basement sills are common areas where the material may fallen and become visible. 


Q. Should I Test The Vermiculite for Asbestos Content?


  At this point in time, due to the lack of a standard testing protocol for quantifying asbestos fibers in vermiculite we move forward assuming  ALL vermiculite of unknown origin previously installed in attics/walls contains asbestos. However, If you do choose to have the vermiculite tested for asbestos content we strongly recommend finding a lab that has extensive experience identifying asbestos containing fibers within vermiculite:   www.emsl.com  is a lab known to have experience in this realm.    The Massachusetts DEP has a guidance document that explains a bit more about vermiculite testing (page 10)


If the decision is made to test vermiculite for asbestos content we recommend utilizing the ASTM TEM Qualitative Test for identifying Libby Amphibole Fibers in Vermiculite as the test of choice (determining a percentage is not feasible).  


Q. I Had the Vermiculite in My Attic Tested and the Report Says That it Contains Asbestos.. yet is below the MA Regulation 1% Threshold.  What Does This Mean and Do I Still Need to Get This Removed as an Asbestos Containing Material?


   The verification that asbestos fibers are present within the vermiculite (in any amount/percentage/trace) is, in "expert opinion", reason enough to consider having the material removed & disposed of properly by a licensed asbestos abatement professional.   We take this position as well because it is well known that asbestos was not "added" to the vermiculite at Libby during the processing steps (except for Monokote 3), rather, it was already mixed in with the raw vermiculite ore from the mine of origin.  Veins of asbestos mixed in with the vermiculite ore was and is still present in the mines of Libby, Montana.  The mined vermiculite ore was not refined or mixed into a pulp/slurry and then turned into a consistent end product.  Instead it was randomly milled and heated... with the end result being that the asbestos fibers were randomly strewn throughout the final product.  What this means is that current "known" testing procedures often used by labs can not test for "true percentages" of asbestos content within vermiculite...it is just far too random to test.  The 1% or greater threshold rule that is used as the benchmark to gauge whether a material needs to be handled as an asbestos containing material here in MA  really does not offer much help/guidance when dealing with the Zonolite ore/vermiculite attic insulation issue.  Asbestos tiles, asbestos paper, asbestos pipe insulation, asbestos mastic adhesive: all of these products were processed as a consistently mixed pulp during their manufacturing process. This type of processing means testing a small portion of these "homogeneous" products gives you a very accurate representation of the representative material, as a whole.  This is not the same for testing a small portion of vermiculite and then considering the results as a true representation of the entire installed product.  There is a huge difference here that needs to be taken into consideration. 


Q. What Can Cause My Family to be Exposed to Asbestos Fibers in Vermiculite? Is it Really a Problem, or Just Hype?


   The vermiculite ore that originated from the mine(s) in Libby, Montana is proven to be contaminated with various forms of amphibole asbestos. This is a known fact with incredible amounts of published studies.  The types of amphibole asbestos found (frequently called Libby Amphibole) Winchite, Richterite & Tremolite can pose a significant health risk to you, your family and those invited to work in your home if the material is disturbed and then either inhaled or ingested.   When vermiculite (Zonolite ore) is disturbed it can release asbestos fibers into the air which increases the risk of lung cancer, mesothelioma, asbestosis and other asbestos related diseases. If the area containing the vermiculite is avoided and left undisturbed, then risk of exposure to asbestos fibers is decreased. However, for various reasons, it often proves necessary to access an attic area.  Activities such as plumbing repairs, fixing roof & chimney leaks/deterioration, mold remediation from improper venting, solar panel installation, rodent removal, electrical upgrades (knob & tube wiring) or recessed lighting installation, heating/cooling installation/repair/replacement, installing upgraded insulation to prevent Ice damming or a responsible citizens attempt to do your part in the battle against climate change,...etc.. are just some of the reasons that necessitate attic entry.  (Not to mention storing all the holiday ornaments/presents!)  Avoiding entering attics often is just not feasible...which is why we highly recommend that all vermiculite be removed when possible and when the timing is right. 

For more information from the EPA website regarding vermiculite attic insulation click HERE.

This website has some interesting information as well:



Q. What is the Zonolite Attic Insulation Trust Fund?


    As of February 3, 2014, W.R. Grace is funding the Zonolite Attic Insulation Trust. This Trust will run for a minimum of 20 years and will allow for partial reimbursement of the cost to remove vermiculite insulation under the ZAI brand name.   Their website is www.zonoliteatticinsulation.com 

If you had vermiculite removed prior to the 2/3/2014 date you are still eligible for claim submission under their guidelines. 

Q. Who Can Make A Claim?


   If ZAI was installed into a structure which you own or rented, and you have incurred expenses by either removing, abating, or containing the ZAI, you are entitled to submit a claim. In order for the claim to be successful, you must establish that the vermiculite is the Zonolite ore product, provide documentation of spent funds on removing, abating, or containing the ZAI, and provide proof that you either owned or were a tenant of the structure that contained the ZAI.  We strongly recommend emailing the ZAI Trust with any and all questions about the claims process if you cannot find the answers from their website. 

Q. How do I go about figuring out if I have Zonolite Attic Insulation?

  If you have a discarded bag of vermiculite in your attic with the label “Zonolite” on it then the chances are very high that all the vermiculite in the space is the Zonolite brand.  Please refrain from stirring up any dust near this product and if you need to go into the space for any reason we recommend protecting yourself with a HEPA filtered mask.  If you do not have an easily identifiable discarded bag of Zonolite in the attic or no other evidence that this is the type of vermiculite present (receipt from purchase), then contact us for an inspection.  Please note, even though you may have a bag of vermiculite that does not have markings displaying the “Zonolite” brand name it is known that other vermiculite processors purchased Zonolite ore and applied their own brand name to the packaging….so don’t be fooled by a label.  


If your situation requires that you identify whether your vermiculite is Zonolite we have obtained permission from the ZAI Trust to expedite this process in a shortened period of time (2 weeks or less).   The Lab which handles the sample will be looking for the level of a non-asbestos mineral called Barium.  Fortunately, Barium just so happened to be prevalent within the vermiculite ore which originated from the mine(s) in and around Libby, Montana.  If this level of Barium reaches a certain threshold then it is considered to be the Zonolite ore product.  We are currently not charging a fee for this expedited service.  Our experience with this step is crucial and we will guide you through the process that follows.  The ZAI Trust will also accept samples directly from claimants for this Barium test if you prefer, yet the turnaround times can take 4-6 weeks (or longer) for verification.  The ZAI Trust does not charge a fee for this service and the cost of mailing the sample to their office is usually $4 to $6.   We strongly urge having us take the sample due to there being the possibility that more than one type of vermiculite may have been added to the attic space over the years.   Sometimes multiple samples will need to be submitted if this happens to be the situation.   Please note: If the vermiculite is shown to have a low Barium count this does not mean that the vermiculite is free of asbestos contamination and a high Barium count does not necessarily mean that the material contains asbestos.  This test is designed to provide "origination" for the ZAI Trust.  For claimants, knowing what the product is allows for informed decisions on dealing with the elevated probability of asbestos contamination. 


Q. How Much Will I Be Reimbursed?


   In short, the Trust will reimburse up to 55% of the total cost of removal, abatement, or containment, and re-insulation, (as long as the re-insulation costs are reasonably related to the size of the vermiculite abatement) with a maximum reimbursement of $4,203.37 change at a total cost of $7,642.50.   The ZAI Trust has guidelines for what they will and and will not cover in a claim.  Please contact them for clarification. 


Reimbursement Examples:


If: Total Cost = $5,000   Then: Reimbursement = $2,750

If: Total Cost = $7,000   Then: Reimbursement = $3,850

If: Total Cost = $7,642.50  Then: Reimbursement = $4,203.37

If: Total Cost = $10,000  Then: Reimbursement = $4,203.37

If: Total Cost = $18,000  Then: Reimbursement = $4,203.37


For more information visit the ZAI Trust website by clicking HERE.

--Barrier Mitigation Grants & Heat Loan info for Vermiculite can be found here: