Asked by: Mousa Rass
home and garden indoor environmental quality

Which is better blown in fiberglass or cellulose?

Last Updated: 27th February, 2020

At 3.5 per inch of material, the R-value of blown-in cellulose is 23% better per inch than fiberglass batts! According to research done at the Oak Ridge National Lab, fiberglass loses up to 50% of its R-value in very cold conditions; making cellulose a better choice for homes in northern climates.

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Thereof, is blown in fiberglass better than cellulose?

Blown-in insulation is an excellent choice to insulate an existing attic because it can enhance the attic's R-value. 2.1 – 2.7 R per inch while Cellulose has an R-value of 3.5- 3.7 per inch. Cellulose is found to be more efficient at retaining its R-value across variety of temperatures than fiberglass.

Also Know, what type of blown in insulation is best? The best insulation options for an attic are open cell spray foam, fiberglass, and cellulose.

  • Cellulose is the oldest insulation material used for not only the attic, but other areas of the home as well.
  • Fiberglass is another traditional insulation material that consists of extremely fine glass fibers.

Accordingly, which is better insulation fiberglass or cellulose?

A given sample of cellulose insulation will provide better thermal performance than an identically sized sample of fiberglass insulation. Per square inch of insulation, cellulose has a higher R-value than fiberglass. With loose fill cellulose insulation, you can achieve an R-value of 3.2 to 3.8 per square inch.

What is the cost difference between cellulose and fiberglass insulation?

Loose-fill cellulose typically costs about $0.50 to $1 per square foot installed. The cost is similar to that of fiberglass batts but, if anything, slightly less. Damp-spray cellulose costs about $0.60 to $1.80 per square foot of wall space.

Related Question Answers

Rudi Juli


Is cellulose insulation dangerous?

Cellulose insulation is safe. It is made of paper, but the chemical treatment provides it with permanent fire resistance. There's been static generated by the fiberglass industry warning that cellulose could burn. But independent testing confirms it's safe and cellulose is approved by all building codes.

Vesna CaƱizares


Kermit Thamry


What is the best material for attic insulation?

Loose-Fill Insulation
Cellulose is the most effective material and has an R-value of 2.2 to 3.8 per inch, but if exposed to moisture it can get moldy.

Irving Toyos


What is the best cellulose insulation?

The best manufacturers of cellulose insulation include GreenFiber, Insulmax, Applegate, and Nu-Wool.

Yeferson Ustohal


Does cellulose insulation lose R value?

Cellulose insulation is the most prone to settling and will undergo a 20 percent loss of R-value due to settling. R-value measures the relative effectiveness of insulation per inch. Blown-in insulation made from rock wool or fiberglass typically loses between 2 and 4 percent of its insulating capacity due to settling.

Touhami Nitti


Is cellulose insulation good for soundproofing?

Before you blow insulation into the wall cavity, it is filled with air, and the air creates a resonant space that actually amplifies incident sound. Loosely-packed cellulose has good sound absorption properties, and because it isn't a skin or eye irritant, it's safer to install than fiberglass.

Dahman Beye


Duncan Hachirov


What is the safest attic insulation?

Blown-in cellulose is an excellent option for an attic because it will fill all the joist spaces completely with very few air gaps.
  • Loose cellulose is made of 85-percent recycled material, mostly ground-up newspaper.
  • It resists rot and mildew, and is treated with boric acid as a fire retardant.

Carroll Rebordosa


Is it OK to put cellulose insulation over fiberglass?

Any type of attic insulation can be installed over any other type: fiberglass over cellulose, cellulose over fiberglass -- it makes no difference. The fiberglass must be unfaced, however, or encased in perforated poly bags. Otherwise, condensation could develop on the facing.

Svein Pujolar


How many inches R value?

Comparative Insulation R-Values
Insulation Type: R-Value per Inch:
Fiberglass (batts) 2.9 – 3.8
Cellulose (loose) 3.1 – 3.8
Stone Wool (loose) 2.2 – 3.3
Stone Wool (batts) 3.3 – 4.2

Arno Gloaguen


What is fiberglass made of?

Fibreglass or glass fibre is a reinforced plastic material which is composed of a woven material that is embedded with glass fibres which are randomly laid across each other and held together with a binding substance. Fibreglass is combined with resin to form an extremely strong and durable composite.

Gamal Puerma


How many bags of cellulose insulation do I need?

Average Cost of Blown-In Fiberglass Insulation
R-Value Bags Per 1,000 Sq. Ft. Installed Thickness (Inches)
R-38 20 13
R-44 23 14.75
R-49 26 16.5
R-60 32 20

Ciria Soma


How much is a roll of insulation?

A roll of insulation costs about $0.80 to $1.00 per square foot. The price fluctuates depending on the brand, material, thickness and R-value of the insulation.

Suleiman Sherak


What is cellulose made of?

Cellulose. Cellulose is the most abundant organic molecule in nature. It is a polysaccharide assembled from glucose monomer units, and it (together with other materials such as hemicellulose and lignin) is the main constituent of plant cell walls.

Yujun Mitlacher


Is cellulose insulation itchy?

Does cellulose insulation cause skin irritation? No. Cellulose insulation does not contain any glass fibers, such as found in fiberglass insulation, that cause skin and respiratory irritation.

Dioscoro Haptahaev


Why is fiberglass insulation so expensive?

The higher the R-value, the greater its thermal resistance. Insulations with a higher R-value will be denser, thicker and contain more air pockets. That is why fiberglass is generally less expensive than other major insulation materials. On the bright side, fiberglass insulation does have a higher R-value than cotton.

Mamadu Langmeyer


What is cheaper blown in insulation or fiberglass?

Fiberglass batts, however, are less expensive, costing on average $0.30 to $0.40 a square foot for 6 inches of insulation. Installation costs for blown-in insulation costs around $2 a square foot, where installation costs for batts is around $1 a square foot.

Sheriff Costeira


How do you know if blown in insulation has asbestos in it?

Signs Insulation May Contain Asbestos
If your insulation is gray-brown or silver-gold, chances are it's time to call a professional. If your loose-fill insulation is a dull gray, and soft – it's a good bet that your insulation is mineral-based and asbestos-free.

Gurgen Bockstaller


How thick should cellulose insulation be in attic?

For loose-fill cellulose, this translates to a total depth ranging from 8 inches up to 16 inches. Fortunately, attic insulation can be upgraded simply by adding more to achieve the recommended total depth in inches, without removing existing insulation.