Vermiculite Asbestos Attic Insulation

Once vermiculite is disturbed millions of asbestos fibers become airborne.

Vermiculite asbestos attic insulation. Of concern is zonolite attic insulation. This insulation was sold in canada under the name of zonolite and was extracted from the libby mine in montana usa. That s good news because most zonolite a type of vermiculite insulation falls into that category. You can also check for markings on the material or its packaging.

It was mined there for more than 50 years ending in 1990. The asbestos found in vermiculite is extremely friable and is the most dangerous type amphibole of asbestos. It may have shiny flakes and or small accordion like pieces see photos above. Vermiculite attic insulation is a pebble like pour in product and is usually light brown gray or gold in color.

When heated to a high temperature flakes of vermiculite expand as much as 8 30 times their original size. One common brand was called zonolite. What made the libby vermiculite so dangerous was its proximity to asbestos deposits. The insulation which was known by the brand name zonolite is most often found in residential attics.

Vermiculite in and of itself is not dangerous. The vermiculite from libby is part of the longest man made environmental disaster in american history. 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. Consider this statement from research titled zonolite attic insulation exposure studies where even the suggested method for removal by the manufacturer grace created a very unsafe condition.

The epa says that vermiculite insulation which is the pebbly stuff found in attics of many older homes is only risky if it contains more than one percent asbestos. The expanded vermiculite is a light weight fire resistant and odorless material and has been used in numerous products including insulation for attics and walls.