Of concern is vermiculite ore produced by the libby mine in montana from the 1920 s to 1990.
Vermiculite in attic canada.
As well as being rich in vermiculite this mine had the misfortune of having a deposit of tremolite a type of asbestos.
It s fire resistant and has strong insulation properties.
The libby mine supplied the majority of the world market in vermiculite based insulation.
It was incorporated into home insulation products branded zonolite attic insulation in.
In order to be eligible for reimbursement a claimant must be able to show.
It was sold as zonolite attic insulation and possibly other brands in canada during that time.
If your attic contains vermiculite.
Vermiculite was once touted as a miracle mineral.
Of concern is zonolite attic insulation.
The good news is that we don t live in our attics.
That vermiculite is the zonolite brand.
The zonolite attic insulation trust zai trust was created to help educate the public about the possible health effects of asbestos containing vermiculite and to provide partial reimbursement for zai removal to qualified claimants.
Vermiculite from the libby mine may contain asbestos.
The mine was closed in 1990.
If an attic is insulated with a thin layer of vermiculite a layer that provides less than the minimum r value required by code it s hard to come up with a good way to improve the insulation layer especially if the ceiling has air leaks.
That s why it s so much better to have an attic with no insulation at all than it is to have an attic with 8 inches of vermiculite.
If vermiculite based insulation is contained and not exposed to the home or interior environment it poses very little risk.
Since most of the vermiculite used in canada was taken from the libby mine the odds are quite good that there is asbestos in the vermiculite in canadian attics.
That s good news because most zonolite a type of vermiculite insulation falls into that category.
To assess the risk of asbestos exposure at a house a sample of the vermiculite would need to be analyzed by a lab.
Extracted from the mine between 1920 and 1990 this vermiculite insulation was sold in large bags mainly but not exclusively under the trademark zonolite attic insulation.
As long as this kind of vermiculite based insulation remains undisturbed behind intact walls or in attic spaces and does not become airborne it should not be a concern.
Previously sold under the name zonolite this material was widely used as thermal insulation in roof spaces loft particularly since consumers could install it themselves.
According to the health canada advisory vermiculite insulation containing amphibole asbestos the best way to minimize your risk of asbestos exposure is to avoid disturbing vermiculite based insulation.
