Asbestos is the name given to a group of naturally occurring, fibrous minerals that are strong and resistant to heat, thus they have been used for years as insulating materials in many residential and commercial buildings. However, asbestos is associated with serious health effects and exposure to asbestos fibers should be avoided. Among the many building products that may contain asbestos, common examples include: pipe insulation, boilers, floor tiles, roofing materials, siding, and more. You can’t tell if a product contains asbestos by its age or by looking at it. Asbestos can only be identified by laboratory analysis.
Vermiculite is a mineral ore that has the unusual property of expanding into accordion-like pieces when subjected to heat. Vermiculite attic insulation from Libby, Montana (Zonolite brand) has been found to contain asbestos, another natural mineral ore. The asbestos found in vermiculite is a low concentration contaminant, not an added component.
To the estimated 35 million homeowners who have vermiculite insulation, the EPA says: “You should assume that vermiculite insulation is from Libby and treat the material as if it contained asbestos by not disturbing it or by using a trained professional if it needs to be removed.”