Fiberglass vs Cellulose vs Spray Foam

Fiberglass Insulation;

Fiberglass insulation comes in rolls or batts of insulation which can’t be used to insulate small areas, gaps or crevices. It can also irritate the mouth, eyes and respiratory system. Because of this, it should not be used in occupied areas. Fiberglass insulation can last from 10 to 25 years if it remains dry. Fiberglass insulation is useless once it becomes wet. Although it is a cheap source of insulation, it has a relatively low R value. Standard fiberglass blankets and batts have an R-value between R-2.9 and R-3.8 per inch.

You can read more about it on the Wikipedia page, found here.

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Cellulose Insulation;

Cellulose insulation is comprised of recycled newspaper which has been treated to make the insulation fire retardant. It is three times heavier than fiberglass insulation. There has been some concern in the past regarding offgassing and the unexplained emission of ammonia and a strong odour. You can read about this in a report published by SCI Engineering, here. Cellulose insulation has a lifetime of 20 to 30 years if it remains dry. Wet-spray cellulose is applied damp. This does not affect its insulative properties. If it becomes inundated with water however, it can become extremely heavy and cause slumping. This leaves sections of the wall or ceiling unevenly filled. Cellulose insulation can act as a mild sound barrier. It has an R-value similar to that of fiberglass. Loose fill cellulose has an R-value between R-3.2 to R-3.8 per inch. Dense-pack cellulose insulation has an R-value of approximately R-4.0 per inch.

You can read more about it on the Wikipedia page, found here.

Spray Foam Insulation;

Spray foam insulation expands to fit the environment. This guarantees an airtight seal, unlike fiberglass or cellulose insulation. Once it dries the foam does not emit any particles, fibres or vapours. This ensures it is perfectly safe to install in occupied areas. Spray foam insulation can last up to 80 years with correct installation and caretaking. Spray foam insulation can add structural integrity, improving shearing and racking strength by up to 300%. It also acts as an efficient sound barrier to external noises, as well as internal machinery. Closed-cell insulation stops air and moisture, whereas open-cell foams are permeable to moisture and impermeable to air. Closed-cell spray foam insulation has an R-value of approximately R-6.5 per inch.


You can find a list of benefits here.


If you are more interested in external insulation please click here.

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