Frequently Asked Questions – Vermiculite Insulation Containing Asbestos

The Government of Canada is informing Canadians about the potential risks to health posed by vermiculite insulation containing asbestos. Some vermiculite insulation may contain asbestos fibres. These products can cause health risks if disturbed during maintenance, renovation or demolition. However, there is currently no evidence of risk to your health if the insulation is sealed behind wallboards and floorboards, isolated in an attic, or otherwise kept from exposure to the interior environment.

View a list of common building materials that might have asbestos:

Asbestos Typical Materials


Am I at risk from my home’s insulation?

If sealed behind wallboards and floorboards, isolated in an attic, or otherwise kept from exposure to the interior environment, vermiculite insulation poses very little risk to health because the asbestos fibres it may contain are unlikely to become airborne and enter the living areas of the home.

It is important to avoid disturbing vermiculite insulation as asbestos poses the greatest health risk when its fibres are present in the air that people breathe. If you plan to remodel or renovate in a manner that would disturb the vermiculite, seek advice from a qualified asbestos professional first.

Does vermiculite insulation contain asbestos?

Of concern is vermiculite ore produced from the Libby Mine in Montana from the 1920s to 1990. This mine supplied the majority of the world market in vermiculite insulation. It has been determined that vermiculite from this mine may contain asbestos.

Products made from vermiculite ore produced by the Libby Mine were not widely used after the mid-1980’s and have not been on the market in Canada for more than 10 years.

Not all vermiculite insulation produced before 1990 contains asbestos. However, it is prudent, in the absence of evidence to the contrary, to assume that vermiculite insulation products produced before 1990 may contain some asbestos.

How do I minimize my risk of exposore?

The best way to minimize your risk of asbestos exposure is to avoid disturbing vermiculite insulation in any way. If isolated in the attic or sealed behind floorboards or wallboards, vermiculite insulation poses very little risk to health.

Is horticultural vermiculite safe?

Based on current information, there is no evidence that vermiculite currently available for horticultural purposes (eg. potting plants) is a health risk if used as directed.

What are the health effects associated with exposure to asbestos?

Asbestos related illnesses are usually associated with frequent and prolonged exposure to asbestos. The time it takes to develop a disease from exposure to asbestos is usually quite long – up to decades.

Exposure to asbestos (by breathing airborne asbestos fibres into the lungs) has been associated with the development of mesothelioma (a rare form of cancer), asbestosis (a serious, progressive, long term disease of the lungs) and lung cancer.

Various factors determine how exposure to asbestos affects an individual:the concentration of asbestos fibres in the air;

  • how long the exposure lasted;
  • how often the person was exposed;
  • the size of the asbestos fibres inhaled;
  • the amount of time since initial exposure.
What can I do to protect myself and my family?

If the insulation is not exposed to your living space in your house, and is not being disturbed, it poses very little risk to health. The important thing is not to touch or disturb it. If you think you have vermiculite insulation in your attic, you should take these precautionary steps:

  • Do not touch or disturb it;
  • Do not allow children to play in the attic;
  • Do not use the attic for storage if retrieving items from it may disturb the insulation;
  • If you are currently using the attic for storage and are concerned, contact your local health authority for advice on what to do;
  • If you find vermiculite insulation on the floor, contact your local health authority for advice on what to do;
  • If you absolutely must go into the attic, make sure that you do not disturb the insulation. Do not remain in the attic any longer than absolutely necessary;
  • If you plan to remodel or renovate in a way that might disturb the vermiculite insulation, seek advice from a qualified asbestos professional first;
  • Never attempt to remove insulation yourself; and,
  • Make sure anyone working in the attic knows about the possibility of the presence of asbestos.

If you have concerns about your health due to possible exposure to asbestos, you should talk to your doctor or primary health care provider.

What is vermiculite?

Vermiculite is a naturally occurring mineral mined around the world. It has been used in numerous commercial and consumer products, including insulation since the 1920’s. It has not been shown to pose a health problem, and no serious health risks have been found resulting from exposure to vermiculite.

Will the Government of Canada ban the production and sale of asbestos?

Not all types of asbestos are the same. The only type of asbestos mined in Canada today is chrysotile asbestos which has very different properties from the tremolite variety thought to be contained in Zonolite (R) insulation. Products made with chrysotile fibres, such as chrysotile cement products, when produced and used under controlled conditions, do not pose any discernable risk to human health.