Vermiculite and Asbestos Insulation

Over the years, a wide variety of materials have been used to insulate homes and other buildings. Sawdust, corn cobs and straw are some naturally-occurring materials that have been used as insulation in the past. Vermiculite insulation also belongs in this category.

Vermiculite is a mineral that is light and shiny, like mica, with a similar flaky texture. When heated to high temperatures, vermiculite expands and gains the qualities that make it an effective insulator -- a lightweight, porous, fire-resistant material. Pieces of vermiculite insulation can be up to an inch long, but most are smaller pieces and particles.

Although vermiculite insulation is still available today, it's used more for specialized applications rather than for home insulation. Older houses may still contain vermiculite insulation, which resembles kitty litter in appearance.

Asbestos Mixed In With Vermiculite

Most vermiculite insulation used in the U.S. came from a single mine in Montana where asbestos was also mined. Consequently, it's likely that old vermiculite insulation may contain some asbestos fibers. If you find old vermiculite insulation in your house, follow these safety procedures:

• Don't disturb the vermiculite. Inhaling asbestos fibers can cause serious respiratory ailments. Leaving the material undisturbed is the best way to ensure that asbestos fibers don't become airborne. Don't allow children to play around vermiculite insulation.
• Do not attempt to move or remove the vermiculite yourself.
• New insulation can be installed on top of old vermiculite insulation, but the insulation contractor must make sure not to move or otherwise disturb the vermiculite.
• If you must move or remove old vermiculite insulation due to remodeling or other plans, hire an asbestos abatement contractor to do the job.

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