How To Tell The Difference Between Cellulose And Asbestos Insulation

A properly insulated home ensures that its occupants are comfortable and it also helps to lower heating costs. Asbestos insulation was very popular for several decades but was banned because of the risk to human health. Cellulose insulation is a safe alternative that has become standard for many homes. It can be difficult to identify whether you are dealing with asbestos or cellulose insulation but some telltale signs can help you to tell the difference.

Asbestos is extremely hazardous to human health. If you suspect that you may have asbestos insulation in your home, it is important to get it tested and removed by professionals. Never try to remove asbestos yourself. At Asbestos SOS, we will conduct thorough testing of any suspected asbestos-containing materials and remove them safely from your home.

Cellulose vs Asbestos Insulation

What Is Asbestos Insulation?

Asbestos is a naturally occurring mineral that is formed of tiny fibres. These fibres, in turn, are made up of microscopic fibrils.

Asbestos has been used as a construction material for hundreds of years, and it became especially popular in shipbuilding during the 19th century. During the 20th century, it was used throughout homes and commercial buildings. The peak of asbestos use was in the 1960s and 1970s.

Its widespread popularity was due to its unique attributes, including its heat, electricity, water, and fire-resistant properties. It is also an excellent heat and sound insulator and it is cheap and versatile to use.

Learn more: What Does Asbestos Look Like

Asbestos Insulation

Why Was Asbestos Banned?

There were concerns about the health risks associated with asbestos long before it was banned. Three types of asbestos were most often used as construction materials in the UK:

  • blue asbestos (crocidolite)
  • white asbestos (chrysolite)
  • brown asbestos (amosite)

Brown and blue asbestos were banned in 1985 and white asbestos was banned much later in 1999.

When people inhale or ingest asbestos fibres and fibrils, they can't be broken down by the body. Over decades, these fibres can cause serious and fatal diseases, including:

  • lung cancer, ovarian cancer, and laryngeal cancer
  • mesothelioma
  • asbestosis
  • COPD

In total, an average of 5,000 people a year die of asbestos-related diseases. Many of these are construction workers who are more often exposed to asbestos. Because the disease takes many decades to trigger these diseases, it was difficult at first to pinpoint the cause.

Types Of Asbestos Insulation

Asbestos is an excellent insulator. Its fibres create a cotton-like substance that efficiently traps heat and slows down its escape.

Asbestos insulation is often seen in attics, walls, and ceilings to insulate the property itself but you can also find asbestos insulation spray used as pipe insulation, as well as boilers, electrical elements, and fireplaces/furnaces.

Check out: Asbestos Pipe Insulation And Lagging Removal Cost

Wet Vs Dry Asbestos Insulation

Dry asbestos insulation is asbestos that is packed tightly into spaces to create insulation. This type of asbestos insulation can be everything from pure loose-fill insulation to a mixed material with a relatively low asbestos content.

Wet asbestos is asbestos mixed with water so that it can be applied using a wet spray.

Vermiculite Insulation

Vermiculite insulation is not asbestos, although it is a similar mineral with insulating properties. However, due to contamination at vermiculite mines, a large proportion of vermiculite insulation will also contain asbestos.

Vermiculite Insulation

Loose-Fill Asbestos Insulation

This is the most potentially dangerous form of asbestos insulation. Loose-fill insulation will often contain pure asbestos that is poured into hollow spaces to create asbestos attic insulation or within wall cavities.

If the cavity is opened, even the smallest movement or breeze will lift the fibres and disperse them into the air where they can be inhaled.

Loose Fill Asbestos Insulation

Sprayed Asbestos Insulation

This type of asbestos insulation uses wet asbestos that is sprayed onto ceilings, walls, and beams. It can easily crumble making the fibres airborne.

Sprayed Asbestos Insulation

Wrapped Asbestos Insulation

This type of insulation was usually made out of asbestos wool insulation or asbestos paper insulation. It was often used as asbestos pipe insulation. As the materials degrade, the asbestos can become crumbly which can cause the fibres to break free and release asbestos dust into the air.

Explore further: Asbestos Pipe Insulation Removal

Wrapped Asbestos Insulation

Asbestos Insulating Board

Asbestos Insulating Board (AIB) was a common type of asbestos insulation. It is blocks of, often, almost pure asbestos that can be affixed to walls, ceilings, behind fireplaces, and more.

Asbestos Insulating Board 1

What Is Cellulose Insulation?

Cellulose insulation is an environmentally friendly, natural, and safe insulation material. It can be made from various materials but is usually mainly recycled paper products and denim, although straw and hemp can often also be added.

Like asbestos, cellulose's insulating properties come from its fibres. These fibres create air pockets that slow down the transference of heat.

Cellulose is one of the earliest insulation materials but it didn't become popular until the 1950s. This is mainly because paper pulp and other similar materials are highly flammable and they also degrade very quickly when wet.

Cellulose insulation is now treated with a variety of agents to give it water and fire-resistant properties. This will often be boric acid or ammonium sulfate and the material is heavily treated with the additives making up a good chunk of the total percentage.

Cellulose Insulation

Types Of Cellulose Insulation

Cellulose insulation can be used in the same way as asbestos insulation.

  • Dry cellulose insulation can be blown into attic cavities as loose-fill insulation or densely packed into walls and ceilings.
  • Wet spray cellulose insulation can be used for a variety of applications. The wetness allows it to adhere well to the surface of the cavity being insulated.

Cellulose

How To Tell The Difference Between Cellulose And Asbestos Insulation

It can be difficult to see the difference between asbestos and cellulose insulation. At first glance, the two appear very similar. They are very different materials, however, and the differences can be apparent in some cases.

Similarities Between Cellulose And Asbestos Insulation

Asbestos and cellulose insulation share some attributes, including:

  • They are both dense, fluffy, and often lumpy
  • They can both be dry and crumbly
  • They can both be brown, grey, or white

Differences Between Asbestos And Cellulose Insulation

Some key features can help you figure out how to tell the difference between cellulose and asbestos insulation.

Texture

When exposed, cellulose insulation will look like shredded paper.

Asbestos insulation, on the other hand, will often take on a pebble-like appearance. The asbestos fibres will sometimes be clearly visible.

Colour

Both cellulose and asbestos insulation can vary in colour, which can make telling the difference more difficult. Asbestos insulation, however, is usually a light brown, white, or silver-gold colour.

Cellulose insulation, on the other hand, will often be green or pink. Which can make it look much different from asbestos insulation.

Asbestos Testing

If you have an older home with insulation materials that were put in sometime in the 20th century, then there is a chance that they may contain asbestos. Especially if the insulation was installed between 1960 and 1980.

If you are unsure about the insulation in your home and think that there's a possibility it could contain asbestos, you should not try to move or interfere with it at all. Asbestos can be very dangerous, especially if the asbestos particles are released into the air. Before any work is done, asbestos testing should be completed.

Contact us at Asbestos SOS if you need asbestos testing on your insulation. Our team of experienced professionals is well-equipped to deal with the high-risk nature of asbestos and will take all of the necessary safety precautions to ensure their safety. Once testing is complete, we can discuss the plan for removal with you (if the insulation does contain asbestos).

Asbestos Testing 1

Final Thoughts

Cellulose insulation, asbestos insulation, and fibreglass insulation are the most common insulation types. Telling the difference between cellulose and asbestos insulation can be difficult because they can appear quite similar to the naked eye. Both contain fibres and both can be crumbly and lumpy. Asbestos will often look more like pebbles, however, and cellulose more like shredded paper. And cellulose can be green and pink whereas asbestos will usually be light brown, white, or silver-gold. If you have any doubt that your insulation could be asbestos, you should call in asbestos removal contractors for thorough testing and safe removal of the material.

Consult with Our Asbestos Removal Experts

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Removal Experts

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