Zonolite Insulation


The History of Zonolite Insulation

zonolite attic
Zonolite in an attic

The history of Zonolite Insulation began when E.N. Alley launched his vermiculite mining business in Libby, Montana. Alley created the Zonolite brand as a commercial name for the mineral, and more than 40 years later, in 1963, his business was acquired by W.R. Grace and Company, becoming the Zonolite Division.

By the time W.R. Grace took over the operation, the asbestos hazard in the United States had become clear. Asbestos dust was evident in the causality of lung diseases and deaths among vermiculite miners and processing plant workers. The company’s executives, however, ignored this information while continuing to growing the Zonolite business throughout the 1970s; even as more employees and residents of the town fell ill from asbestos exposure.

It was estimated that W.R. Grace processed nearly 200,000 tons of vermiculite from the Libby mine each year until the mine finally ceased operations in 1990; far too late to spare W.R. Grace from the wave of lawsuits to come. The Libby mine and surrounding areas were declared a superfund site in 2002, and the EPA now advises all American homeowners to take extreme caution with Zonolite insulation found in attics.


What is Vermiculite?

Vermiculite (Mineral)

Vermiculite is a naturally occurring mineral with a silver-gold or light brown color. From a distance, vermiculite insulation resembles pebbles or gravel, and it fades to a grey color over time.The product itself is a very lightweight material because vermiculite has the unique ability to be puffed out when heated, much like popcorn.

Most Zonolite was contaminated with a highly toxic form of asbestos because of where the vermiculite was mined. Vermiculite and asbestos have much in common: Both are resistant to fire and chemical corrosion, and both make excellent insulating materials. They also occurred in the same geological formation mined by W.R. Grace and Company, which is why most Zonolite is dangerous. Pure vermiculite is harmless, but vermiculite mined alongside asbestos posed a serious risk for asbestos exposure.

During the decades when Zonolite was manufactured, most of the world’s supply of vermiculite came from the town of Libby, Montana. The area became so contaminated by asbestos that the U.S. Environmental Protection Agency (EPA) has now been working to clean the area up for almost 20 years.

Zonolite and asbestos

Asbestos (Mineral)

The asbestos that contaminates most Zonolite is called tremolite. This noncommercial variety is described as an amphibole form of asbestos because its crystal fibers are straight rather than curly. Therefore, it takes less exposure for tremolite to cause asbestos-related disease, compared to the more common chrysotile. Some studies suggest tremolite could be 10 times more dangerous.

People having the greatest risk of developing an illness such as asbestosis or malignant mesothelioma was when they were exposed to asbestos dust on a regular basis (over many years), or any activity that disturbs Zonolite, releasing microscopic asbestos fibers into the air.

Contractors that worked with contaminated Zonolite directly during home construction or renovation created a major exposure risk. Even simple tasks, such as moving things around in an attic or working on ceiling fixtures, could have lead to enough cumulative exposure over the years to cause an asbestos-related illness. In the end, there is no safe level of asbestos exposure.

It only takes being exposed to asbestos one time to get mesothelioma and other lung diseases. Some of these illnesses can take 20-40 years to show symptoms after exposure. 

What to do if my home has Zonolite Insulation?

If you find vermiculite insulation in your home, the most important step is not to disturb it. Asbestos is only a danger if it becomes airborne. Sometimes the best solution is to leave the insulation in place, and take steps to protect your home against any airborne asbestos particles.

Assume Asbestos Contamination: There’s no firm cut off date for asbestos contaminated insulation; so to be safe, treat all vermiculite insulation as if it contains asbestos. 

Do Not Disturb Vermiculite: Never stir, handle, or move vermiculite insulation, or do anything to it that might create dust. Even small movements can send asbestos particles into the air. If the asbestos is undisturbed, and it’s sealed away from your home’s living space (such as in a ventilated attic or inside the walls), many homeowners decide to leave vermiculite insulation alone, rather than spending thousands of dollars on remediation. The crumbled texture of this attic insulation leaves asbestos exposed to anything that might disturb it. Because it’s not sealed, Zonolite asbestos might easily become friable or airborne.

Hire a Professional Asbestos Removal Contractor: If you’re doing remodeling that will stir up vermiculite insulation or you want to remediate the building, be sure to hire a professional asbestos removal contractor. Professional negative pressure systems are designed to protect your living space from air contamination during the removal process. At the very least, have someone inspect your home to make recommendations for encapsulating the insulation and preventing leakage.

Keep Out of Contaminated Areas: Don’t store anything in attics insulated with vermiculite, and make the area is off limits.

Seal Off Vermiculite Insulation: Make sure any area containing vermiculite insulation is sealed off from the interior of your home. Use caulk or spray foam around seams, light fixtures, fans, and switches, as well as plumbing pipes or other openings where insulation dust might filter in. Hire an asbestos contractor to install attic flooring that completely covers and seals off the insulation.

Warn Workers About Vermiculite Insulation: Talk with anyone working on your home to make sure they understand the risks of working around vermiculite insulation. Special precautions should be taken before cutting a hole in the walls or ceilings if the vermiculite insulation might be disturbed. You may also want to put up signs in the attic, as a warning to workers who may disturb the insulation by accident.

Wear Protection Around Vermiculite Insulation: If you must be exposed to the insulation for even short periods of time, wear goggles and a HEPA respirator (not just a dust mask). Walk only on the floored part of the attic, and don’t touch or disturb the vermiculite particles.

Remember that it’s much better not to have ANY contact with vermiculite insulation!


Lawsuits and Trust Fund

Throughout the 1990s, so many personal injury and property damage lawsuits were filed against W.R. Grace over asbestos exposure that the company finally sought Chapter 11 bankruptcy protection in 2001, along with 61 of its affiliates. After a drawn-out legal process, the plan of reorganization was confirmed in 2011, becoming effective in 2014.

The reorganization required W.R. Grace to set up two separate trust funds to provide compensation to present and future victims of asbestos exposure.

  1. The Zonolite Attic Insulation Trust helps homeowners who have asbestos insulation get rid of it safely. They also help with re-insulation. The Trust will reimburse homeowners 55 percent of the cost of removal and new insulation. 
  2. The W.R. Grace & Co. Asbestos Personal Injury Trust compensates individuals and families who have suffered because of asbestos-related illnesses caused by W.R. Grace operations and products.

Combined, these two trusts are worth more than $4 billion. Payments totaled more than $353 million in 2015, with thousands of claimants receiving compensation.




Sources: https://www.asbestos.com/products/zonolite-insulation

Vermiculite Insulation: Is it Really a Risk if it’s in the Attic?


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