Vermiculite is a mineral based insulation that was used as a pour in retrofit insulation material from the 40’s to the 80’s. Unfortunately, it was recently discovered that the mine which produced most of the vermiculite used in Canada was contaminated with asbestos.

As a result, there is a risk of asbestos exposure whenever vermiculite is found in a house. The test to determine the presence of asbestos is beyond the scope of a home inspection, and must be carried out by a lab. There are several local labs able to do this work.

If asbestos is found in the vermiculite, then the next question is what to do about it. Removal of the vermiculite is the best long term answer, but it is very expensive. Also, as the attic is not normally used, it may be possible to simply contain the vermiculite and not enter the space. Obviously, resale value can be affected by the presence of asbestos.

Asbestos in Vermiculite/Zonolite

http://www.gov.mb.ca/labour/safety/pdf/bulletins/bltn245.pdf
http://www.osha.gov/SHTC/asbestos/index.html
http://www.hc-sc.gc.ca/iyh-vsv/prod/insulation-isolant_e.html
http://www.epa.gov/asbestos/pubs/insulation.html
http://www.epa.gov/asbestos/pubs/verm.html
http://www.cdc.gov/niosh/docs/2003-141/
http://www.gov.mb.ca/health/publichealth/cmoh/vermiculite.html