Asbestos Insulation: Why Is It Dangerous?

Asbestos insulation contains tiny fibers, some needle-like, that are easy to inhale. Since the lungs can’t expel these fibers, they can lead to a number of cancers and respiratory diseases. Asbestos insulation has been connected to asbestosis, lung cancer, mesothelioma, ovarian cancer, and laryngeal cancer, among other health problems.

But before you go into panic mode, it’s important to know that asbestos is most dangerous when disturbed. When undisturbed, the fibers don’t float in the air and pose a much lower risk of disease.

Asbestos Insulation

What Is Asbestos?

Asbestos is a naturally occurring silicate mineral with long thin fibrous fibers. These fibers are composed of microscopic “fibrils” that are released into the atmosphere by abrasion, among other processes.

This unique type of fiber allows asbestos to be turned into cotton-like material, making it easy to handle and mix with other materials.

Asbestos History and Uses

Asbestos is an excellent thermal insulation material and electrical insulator. It is very fire-resistant. (The name “asbestos” is derived from Greek meaning “inextinguishable” and refers to lamp wicks that never burn up.)

Many developing countries support the use of asbestos in building construction. In 2020, Russia, the world’s largest producer, mined approximately 790,000 tons of asbestos.

Asbestos has been used for thousands of years to create flexible products that will resist heat and not burn up. Industrial-scale mining began in the 1870s allowing asbestos to be adapted for use in more products. Some products include:

  • Boilers
  • Cement pipe
  • Automotive components like brake pads, clutches, and transmission parts
  • Electric motor components
  • Heat protective pads
  • Paper products

Today, the limits placed on asbestos have reduced the number of products containing asbestos. All of them are imported and include:

  • Automobile Clutches
  • Brake Pads
  • Corrugated Sheathing
  • Cement Pipe
  • Roofing Materials
  • Vinyl tile

Asbestos Insulation Uses and Types

During most of the 20th century, the majority of insulation products contained asbestos. Almost every house built before 1975 has asbestos in it. It was even used to manufacture blankets for hospitals.

The construction industry became an early enthusiastic user of asbestos. Vermiculite was used for wall and attic insulation from about 1919 – 1990. It’s lightweight, fire-resistant, odorless, and provides R-2.0 per inch.

Asbestos was also used in the manufacture of drywall, drywall mud, and asbestos siding. By the end of the 19th century, construction uses included fireproof coatings, pipe insulation, concrete, bricks, fireplace cement, ceiling insulation, flooring, and roofing. In 2011, over 50% of British homes still contained asbestos despite a years-old ban.

Spray-on Asbestos Insulation

Spray-on insulation is used on ceilings, walls, and beams to create a fireproof insulating blanket. It is quick and inexpensive. It is most often seen on the ceilings of commercial buildings and factories as a thick gray coating.

Before 1990 many of these coatings contained up to 85% asbestos. Since 1990, spray-on insulation containing more than 1% asbestos must use binders during spraying to encapsulate the fibers.

Loose-Fill Asbestos Insulation

Loose-fill insulation is similar to cellulose blown-in insulation, fiberglass blown-in, or mineral wool blown-in. It is blown loose into attics and wall cavities. The light fluffy cotton-like product looks very similar to white fiberglass.

Asbestos Rigid Board Insulation

Asbestos Insulation Boards (AIB) were glued to concrete walls to provide basement insulation as ceiling tiles, soffits, and partition walls. Made from almost pure asbestos, these rigid boards resemble expanded polystyrene at first glance. Asbestos rigid insulation provides approximately R-2.0 per inch.

Asbestos Wrap Insulation

Contractors have wrapped HVAC pipes, ducting, and some plumbing pipes in asbestos insulation for decades–in houses, commercial buildings, and Navy ships. Before 1980 pipes were wrapped with asbestos-based air cell insulation–a type of cardboard manufactured from asbestos paper. Other pipe insulation, known as asbestos wool insulation–resembling fiberglass pipe wrap–was also used.

What to Do If You Have Asbestos Insulation

Asbestos is friable, which means it crumbles. As asbestos crumbles, it releases microscopic fibers that humans can breathe into the lungs. In many cases, asbestos insulation is reasonably stable. If left undisturbed, the fibrils will stay with the product. Renovating houses containing asbestos is one of the main activities that release asbestos particles into the air, where they can be inhaled or ingested.

You can determine whether you have asbestos insulation via a professional inspector or an at-home test kit. If you have asbestos, a professional abatement company can advise you on the next best steps. But, if the asbestos insulation is in an attic and will remain undisturbed, no further steps may be needed. If you’re planning on renovations or would like the removal of the insulation for peace of mind, your best bet is through an EPA-certified asbestos removal company.

Asbestos Bans

Over 55 countries around the world have banned asbestos use. In some countries, there is a very short list of exceptions for specialized products–such as clutches, brake pads, some roofing materials, and vinyl tile. Some of the countries banning products containing asbestos include the European Union, Japan, Australia, and a handful of African and South American countries.

Notable among the non-compliant countries are Canada, China, the United States, India, and Russia. Asbestos kills about 15,000 Americans yearly, yet over 8 million lbs. is still imported into the country every year.

Prior to 1990, domestic vermiculite containing asbestos was mined at Libby, Montana, and processed at 245 sites around the country. The processed vermiculite was used as home insulation in tens of thousands of homes and in potting soil.