Q. What Year Was Asbestos a Problem in Vermiculite Insulation?

Q. Hi Mark,

My house was built in 1958, according to the date on the chimney, I purchased the house in 2001, and did total renovation, unfortunatly the vermiculite is still in my attic and when the house was inspected before buying it the inspector said that it was fine to leave it. I was wondering if you knew what year the vermiculite had asbestos in it?

Thank you, Caroline

A. Hey Caroline,
Most of the vermiculite used as insulation in north America came from a mine in Libby Montana.  This mine’s vermiculite was contaminated with several large veins of asbestos.  At one time, Asbestos was considered an excellent insulator and fire retardant.  Therefore, initially there wasn’t much concern about the asbestos contaminating the vermiculite. It wasn’t until later, when a connection between asbestos and lung diseases was found, that vermiculite insulation became a concern for homeowners. Unfortunately, there isn’t any particular date that you can count on the vermiculite not containing asbestos. While not all vermiculite contains asbestos (not all vermiculite came from, or currently comes from the Libby mine), most vermiculite insulation does. Or, at least the EPA recommends that you assume it does. Your inspector was correct, in saying you can leave it alone. The concern is when the vermiculite is disturbed either by storing things in the attic, or by renovations. I’d recommend clicking on the download links in the right hand side bar to read more about vermiculite insulation and the EPA’s recommendations to homeowners.
I hope that helps.
Mark