Vermiculite Attic Insulation

What is Vermiculite

Vermiculite is a low density insulation which has the appearance of layers of mica separated by air gaps. Photographs of vermiculite can be found in the US EPA document link below. Vermiculite is not asbestos (and vermiculite sold today does not contain asbestos) but some vermiculite deposits were contaminated with asbestos. Vermiculite was widely sold to home builders and consumers across North America to insulate attics, walls or around chimney liners. It was poured into these areas and was almost self-leveling.

In the US almost all poured vermiculite insulation came from a mine in Libby Montana contaminated with varying amounts of actinolite or tremolite asbestos. This material was sold by W.R. Grace under the trade name Zonolite Attic Insulation (ZAI). However, some of the vermiculite insulation sold in Canada came from asbestos-free deposits, mainly from South Africa. It is therefore important to determine which type of vermiculite you may have in your home. Pinchin’s experience has been that about 60% of the vermiculite attic insulation samples processed by our laboratories contained asbestos. There can be a mixture of both types present because both asbestos and non-asbestos products may have been installed.

How Pinchin Ltd. Can Help

Pinchin Ltd. (Pinchin) can help you determine if your vermiculite insulation contains asbestos and help you solve the problem if it does. We do not generally perform field work on homes, but we can tell you how to take a sample, analyze the sample and give direction and assistance in getting the insulation removed if that is what you want to do. We provide information on collection and analysis of vermiculite. If you decide to have the suspect material analysed (since not all vermiculite contains asbestos) please follow the Recommended Vermiculite/ ZAI Sampling Procedure  provided on this web site. We strongly advise that homeowners confirm that the laboratory that they select is accredited for asbestos analysis and has had experience with vermiculite analysis since we have seen some erroneous analyses from laboratories which do not have experience in vermiculite analysis.  The qualifications of the laboratory may also be important when the home is offered for sale. 

What to Do If Your Home has Vermiculite Insulation

If the insulation in your attic is not being disturbed and your attic is not used for living space or storage, it is normally recommended to leave it in this state. Clear guidance on this is available at the U.S. Environmental Protection Agency. More information can be obtained at Health Canada.

Unfortunately if you own a home with ZAI, you may need to remove the insulation before you can sell your home. A competent home inspection (usually performed by the purchaser) will normally detect vermiculite and we have seen many home sales fail due to its presence. The cost of removal depends on the size of your attic but may approach $10,000 or more to remove and replace the insulation. Homeowners should consider upgrading the insulation and air tightness of their attic at this time to upgrade energy efficiency.

How to Submit a Sample

Detailed instructions on how you should collect your Vermiculite / ZAI (Zonolite Brand Attic Insulation)  sample are provided here.  Please be sure to follow these instructions for your own safety.

EPA Update 2009

On June 23, 2009, the EPA has released updated information concerning Vermiculite as part of launching a public awareness campaign to notify the public about the potential for vermiculite insulation to be contaminated with asbestos fibers. View this new EPA guidance document here:  " Vermiculite - Protect Your Family from Asbestos-Contaminated Vermiculite Insulation".  Note: Zonolite Attic Insulation Claims date was extended to Dec. 31, 2009.