Cellulose Or Fiberglass In Attic

As the temperature difference between the living space and attic increases the r value of blown fiberglass diminishes.

Cellulose or fiberglass in attic.

The two main least expensive and most commonly used residential insulation materials is cellulose and fibreglass. Cellulose has 38 better air infiltration than fiberglass. Blown cellulose is typically the preferred choice of insulation for attics. Cellulose can be blown into existing walls through small access hoses without dismantling the entire wall as with fiberglass batts.

Costs slightly more than fiberglass. Rather than trying to meticulously lay fiberglass insulation over the attic homeowners and builders can simply blow cellulose insulation throughout the attic. When comparing blown in insulation both fiberglass and cellulose are nearly identical in price both costing around 0 70 to 0 80 per square foot for 6 inches of insulation. When using cellulose blown in dry insulation it requires a machine to achieve its purpose and a training session from wherever you rent the blower from.

This is called wind washing. Downsides of cellulose insulation. Cellulose forms a dense continuous mat of insulation in your attic. Loose fill blown fiberglass insulation has another slight problem.

Air moving through a vented attic deposits dirt and dust into fiberglass batts. Loose fill cellulose insulation can settle around and conform to most of the obstructions found in walls and attics. Assuming your current attic insulation is made from fiberglass and has a value of r 13 you d have to add roughly 10 inches of additional fiberglass to hit r 38. Cellulose in walls and the attic also has some soundproofing properties that reduce noise transmission through the house.

Fiberglass batts however are less expensive costing on average 0 30 to 0 40 a square foot for 6 inches of insulation. Fiberglass insulation is the easiest insulation product on the market to install and if installed correctly the most effective product on the market for home attic insulation. Cellulose is more difficult to cheat than fiberglass. You can get to the same place with either material.

When walls are already finished injecting loose fill cellulose insulation is one of the few ways of adding. Or 7 inches of cellulose. Once it has settled fiberglass has an r value of 2 1 2 7 per inch while cellulose has an r value of approximately 3 0 per inch. So what are the advantages and disadvantages of each of these.

This keeps the air from moving within the insulation and from penetrations between the air conditioned space and the attic. Unless you opt for spray foam then the insulation choices normally come down to cellulose and fibreglass.