Cellulose Or Fiberglass In Attic

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.

Cellulose or fiberglass in attic.

This is called wind washing. 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. Costs slightly more than fiberglass. So what are the advantages and disadvantages of each of these.

When walls are already finished injecting loose fill cellulose insulation is one of the few ways of adding. Air moving through a vented attic deposits dirt and dust into fiberglass batts. Since cellulose is blown in it fills all the gaps crevices nooks and crannies in your attic unlike batts that can leave gaps. Loose fill cellulose insulation can settle around and conform to most of the obstructions found in walls and attics.

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. Cellulose forms a dense continuous mat of insulation in your attic. Cellulose is more difficult to cheat than fiberglass. 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. Or 7 inches of cellulose. Unless you opt for spray foam then the insulation choices normally come down to cellulose and fibreglass. Blown cellulose is typically the preferred choice of insulation for attics.

Loose fill blown fiberglass insulation has another slight problem. 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. Downsides of cellulose insulation. Rather than trying to meticulously lay fiberglass insulation over the attic homeowners and builders can simply blow cellulose insulation throughout the attic.

The two main least expensive and most commonly used residential insulation materials is cellulose and fibreglass. This keeps the air from moving within the insulation and from penetrations between the air conditioned space and the attic. Cellulose has 38 better air infiltration than fiberglass. 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.

As the temperature difference between the living space and attic increases the r value of blown fiberglass diminishes. Loose fill cellulose is relatively inexpensive yet still has an r value of about 3 5 per inch of thickness compared to fiberglass r value between r3 to r4 per inch.