Vermiculite is a mica-like mineral used for an extensive amount of consumer products due to its fire resistance and insulating properties.

Vermiculite was a common material used for insulating homes prior to the 1990s. It was used extensively due to its fire-resistant nature. While vermiculite itself does not contain asbestos, over 70% of the world’s production of vermiculite once came from the Libby Mine in Montana, which also contained natural deposits of asbestos, contaminating the vermiculite. Vermiculite from Libby was primarily sold as Zonolite® Attic Insulation in Canada.

The asbestos fibres found in vermiculite from the Libby mine are friable fibres of amphibole asbestos. This type of asbestos is extremely dangerous, as it can become airborne with the slightest agitation and inhaled by the occupants of the home.

Asbestos fibres are a health concern, with prolonged exposures increasing the chance of lung scarring, and even the development of lung disease, lung cancer or mesothelioma.  These diseases can lead to reduced respiratory function and death.  

Vermiculite can often be found as attic insulation or as an insular fill in concrete mortar block walls or wall/ceiling cavities (see Photographs 1-3 below). As not all vermiculite contains asbestos, when it is found in homes it should always be tested by a professional.

Photograph 1: Asbestos contaminated vermiculite found within a dwelling’s attic space.

Photograph 2: Asbestos contaminated vermiculite found within the wall cavity of a commercial building.

Photograph 3: Asbestos contaminated vermiculite insulation found in a ceiling cavity and used in conjunction with loose cellulose insulation.

Testing should be done whenever the material may be disturbed, including before renovation, after a loss, if insulation becomes loose, or if you use an unfinished attic for storage. The removal of asbestos-containing materials, including contaminated vermiculite, must be completed in accordance with specific asbestos abatement protocols, as outlined in Ontario Regulation 278/05.

Contact Roar Engineering to conduct asbestos sampling or provide a remediation assessment to identify hazardous vermiculite and provide you with the protocols required to safely remove vermiculite from any building.