Cellulose vs Asbestos: How To Tell The Difference Visually

Asbestos is a toxic, cancer-causing material that was widely used for insulation purposes a few decades ago. Once the toxic effects of asbestos became known to the public, its use was replaced by cellulose. Many old homes may still have insulation made of asbestos. So how do you know if your home’s insulation has asbestos, how to tell between asbestos and cellulose insulation?

How to tell the difference between cellulose and asbestos insulation

Asbestos insulation is generally pebble-like and is greyish-brown or silver-gold, whereas cellulose insulation is greyish and looks like shredded paper. However, It is hard to tell the difference between asbestos and cellulose insulation visually. The best way to identify whether your insulation is asbestos or cellulose is through a lab test.

Since the quantity of asbestos used in different insulations varies, so do their appearances. Therefore, if you suspect that your home has asbestos insulation, it is recommended to call a professional to assess it.

asbestos vs cellulose: tell the difference
Asbestos vs cellulose insulation

Does old cellulose insulation contain asbestos?

Cellulose insulation does not contain asbestos. In fact, cellulose is a great alternative to asbestos insulation. Some of the old attic insulations used were made of Vermiculite which contained asbestos. However, none of the cellulose insulation available now or back then has asbestos in it.

If you are worried that your old cellulose insulation may contain asbestos, here is a simple test. Take a little portion of the insulation outside and burn it using a blow torch. Cellulose insulation burns but asbestos insulation won’t. Mind that cellulose will burn only as long as you burn it with the torch; it will self-extinguish when you remove the flame. Asbestos insulation, on the other hand, turns red hot and then crumbles; it doesn’t burn.

It is highly unlikely that old blown-in cellulose insulation contains any asbestos. But try the above test if you are so unsure.

What does cellulose insulation look like

Known to be one of the oldest forms of home insulation, cellulose insulation is typically made from recycled paper products, like newsprint, cardboard boxes, and other paper, as a result of which the recycled material content here tends to be up to 85%. To make cellulose, the paper used is shredded to pieces and fiberized, making it feasible to be packed tightly for insulation purposes.

Cellulose insulation
cellulose insulation

Cellulose insulation looks like finely grounded newspapers. Its colors can vary from light to medium grey. Some cellulose insulation can have a slightly brownish tint. The texture of the cellulose insulation remains consistent everywhere it is laid on.

Cellulose insulation can be installed in newly constructed homes and existing structures. The material can be installed following the loose-fill or blown-in insulation method; this is a method where the material used will be shredded or broken into smaller pieces/granules to achieve a fluffy appearance, and densely packed in different areas around the building, such as attics, walls, ceilings, crawl spaces, etc. One huge benefit of blown-in cellulose insulation is that it does not require an additional moisture barrier, which thereby brings down installation costs.

What does asbestos insulations look like

Used since the 1950s, asbestos is a natural mineral known for its corrosion- and heat-resistant properties. Asbestos insulation refers to any building insulation material that contains asbestos. The fibrous nature of this material gives it an appearance and texture similar to cotton, and its ability to slow down heat transfer through its fibers makes it highly heat-resistant.

asbestos insulation looks like
This is what Asbestos insulation look like

Asbestos insulation looks a bit more greyish and shiny than cellulose. They also tend to stay in lumps. However, it is not easy to identify asbestos in insulation visually.

Here is more on: What does asbestos insulation look like

If you live in an older home, chances are high that your building insulation contains a significant percentage of asbestos, and most of it could be in the form of vermiculite, especially in the attic. Luckily it is easy to identify Vermiculite; if it is used in your attic for insulation, it contains asbestos. There was a time when asbestos blown-in insulation was used, but it is unlikely you will find it in your home.

Vermiculite vs cellulose

Vermiculite and cellulose insulation are visually very different. Vermiculite looks pebble like whereas cellulose is fibrous.

Vermiculite vs cellulose insulation visual difference
Vermiculite vs cellulose insulation

If you are afraid that your home insulation may contain asbestos, the easiest thing to do is make sure that you do not have vermiculite insulation. Since most vermiculite is easier to spot than asbestos, you can easily find it, and know whether your home has asbestos or not. Here’s the story of how vermiculite contained asbestos – https://www.asbestos.com/jobsites/libby/

Cellulose vs Asbestos: Advantages & Disadvantages

Advantages of Cellulose


One of the top reasons why cellulose is currently a widely preferred and used insulation materials is that it is environment-friendly. This is because, as mentioned earlier, the material is derived from reused and recycled materials that would otherwise get disposed in landfills.

Low VOC Levels

Blown-in cellulose, according to a report by Healthy Building Science, has low VOC (Volatile Organic Compound) levels – chemicals that are harmful to the environment and human health. In fact, the total VOC (TVOC) of this insulation type is known to be significantly lesser than what is permitted in GREENGUARD certified products.


If you happen to live near a highway or railway tracks, or you generally prefer to be in a quieter environment, cellulose insulation would be the ideal choice for your home. Since the material is a lot denser than many other insulation materials, it has excellent soundproofing ability.

Disadvantages of Cellulose

Not Waterproof

Cellulose is not waterproof by nature. Yes, it can and will be treated with various chemicals during insulation to make it water resistant to an extent; however, if it gets exposed to moisture to an extended period, it can lead to huge problems, including mold.

Fire Hazard

As the major composition in cellulose is recycled paper, it happens to be a fire hazard if not treated with fire retardants during insulation. It is to eliminate this hazard that building codes throughout the country require cellulose insulation to be properly treated with fire retardants before use.

Advantages of Asbestos

  • Asbestos has high heat-resistant capability, which means it does not burn easily.
  • Since its thermal insulation capacity is high, it can make a building more energy-efficient.
  • Asbestos is also weather-proof.
  • It is highly durable, which is why you can still find asbestos insulation intact in any older buildings.
  • The material is less expensive.
  • It is easy to clean and maintain as well.

Disadvantages of Asbestos

  • As many of you would probably be aware, asbestos is extremely dangerous to human health and the environment. The fibrous microparticles in the material, when inhaled or swallowed, can lead to various illnesses.

Risks of Asbestos

Asbestos produces microscopic fibers that can be swallowed or inhaled, which in turn can result in a plethora of issues. Since it is very difficult for the human body to break down asbestos, its toxic fibers, over time, can lead to inflammation, lung cancer, ovarian cancer, mesothelioma, genetic cell damage, and more such illnesses. Due to such risks involved with asbestos, governments around the world have banned its use as an insulation material. But, there are still some insulation materials that contain asbestos, like vermiculite, which need to be identified and replaced.

Is there asbestos in your home insulation?

If you live in a house that was passed down generations or purchased an older property to live in or rent out, it could possibly be insulated with asbestos or other materials containing a percentage of asbestos. But, where can you find asbestos around your building? These are the few places you should check first: attics, crawl spaces, basement, ceilings, walls, and closets.

Frequently Asked Questions

Can you see asbestos fibers with the naked eye?

Unfortunately, you cannot identify asbestos with the naked eye if it is mixed with other materials. For example, you cannot tell if there is asbestos in your cement pipes or floor tile by looking at it. The only way to know if asbestos is present in most materials is by analyzing a sample in a lab.

Where is asbestos most commonly found in a house?

Asbestos can be found in many parts of the house, including the attic and wall insulations, vinyl flooring and adhesives, duct insulations, and in textured paints and patching compounds. But fortunately, new houses do not use asbestos. If your house was built after the 1990s it is likely to be free of asbestos.

Charles John

Experienced HVAC technician with 8 years of experience in the industry. Capable of handling all sorts of heating and cooling equipment as well as proficient in operational management, construction-related techniques such as preventative maintenance, electrical troubleshooting and AutoCAD

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