Insulation: Fiberglass vs Cellulose

Fiberglass or Cellulose Insulation

Which is better?

 Fiberglass and Cellulose are the two most common materials used for insulation. Insulation helps a home retain its valuable cool and hot air, as well as reduces the rate at which heat transfers in and out of the home. But how can we know which type of insulation is best? 

Fiberglass Insulation

Cellulose Insulation

The iconic pink insulation, known as fiberglass insulation, is an inexpensive way of keeping the air you pay for inside your home. It's not only inexpensive but it is also very easy to install. It is fairly common, so much so that most of us have came in contact with the material at some point in their lives. And if you have, you'll know that the iconic pink color isn't the most distinctive property about the fiberglass insulation. The stuff is itchy! Just the mere touch of the stuff is enough to irritate the skin and cause a rash.

Fiberglass Insulation

As you might have guessed, the components that make up the pink, itchy insulation are just that, various fibers, most of which being glass. This cotton candy-like material is a hodge-podge of glass, limestone, soda ash, and sand. The heated glass is fed through a funnel that shreds the glass into smaller and smaller pieces, to the point that the glass itself is indistinguishable with the naked eye. This simple understanding quickly turns the cheap, easy-to-use material very dangerous. Just touching the stuff sends tiny glass shards into the air. And you think that is bad, just imagine breathing that in! 

The particles cannot be seen with the eye but that doesn't make them less dangerous, no matter how small, we are still dealing with glass. Those particles can get lodged into the skin and can cause rashes that take a long time to go away because the glass shards are stuck in the pores of the skin. Breathing the particles in can be a major irritant to a healthy person but a person with breathing issues, such as asthma, can experience far worse conditions due to long exposure to the fiberglass insulation. Not to mention that decaying over time causes excess particles to be released into the air. So if you are working on an older home with fiberglass insulation, use caution! 

Fiberglass Insulation

Safety is key when handling fiberglass insulation, but what about Cellulose? Although the fiberglass is made out of recycled materials, it can be very harmful to us. Cellulose can be a bit more pricey than the alternative but it is much safer to handle! No itchy irritants in this stuff. 

It is made from recycled wood fibers and is treated with fire retardant materials. This means two things: 1, the cellulose insulation is more dense and can fit in much smaller places than fiberglass insulation. This offers more protection against heat transferring in/out of the home. 2, the fire retardant insulation protects against fires. While no material can be fire proof, it can help in emergency situations by slowing the rate at which the flames spread. Unlike fiberglass, which is highly flammable and can actually cause the flames to spread more quickly. 

Cellulose Insulation

It should also be known that insulation does not prevent air flow, it slows it down, and acts more like a blanket. Spray foam insulation is different. It actually prevents the flow of air and is used to seal up cracks, gaps, and wholes. This is typically done first and Cellulose (preferably) or Fiberglass insulation then placed in the areas of concern. 

With these precautions and information, you now are able to get your home properly insulated! Keep in mind that if you are living in an older home with fiberglass, the insulation worn and will be broken down, causing more glass particles to be airborne. Additionally, the home might not be air sealed properly. 

It is safe to say that despite the condition of your home, cellulose insulation is the better choice. With proper air sealing and the proper amount of cellulose insulation, your days of wasting precious air (that you pay for) are long gone! 

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