Blown In Fiberglass Vs Cellulose Attic

Rather than trying to meticulously lay fiberglass insulation over the attic homeowners and builders can simply blow cellulose insulation throughout the attic.

Blown in fiberglass vs cellulose attic.

As a recycled paper product cellulose is prone to absorb moisture that can cause wood rot and mould. Cellulose has a higher r value and even does not lose the value in the extreme cold were fiberglass may. Fiberglass blown in involves using a machine to pump 2 the loose insulation into the wall cavities. Or 7 inches of cellulose.

According to research done at the oak ridge national lab fiberglass loses up to 50 of its r value in very cold conditions. Cellulose is easier to keep out of bird blocks and air conditioner condensate pans. This is slightly more difficult but provides better installation. Cellulose produces much less static than fiberglass.

Cellulose resists blowing when installed fiberglass tends to blow around stick to the attic ceiling and drift. Dry blown cellulose will characteristically settle and sag in place reducing its r value. This allows the insulation to get into the small pockets and crevices that fiberglass wouldn t be able to. Which means cellulose insulation can be compressed into a space and offer additional r value.

You can get to the same place with either material. By nature the cells inside the cellulose insulation have their own insulating power. At 3 5 per inch of material the r value of blown in cellulose is 23 better per inch than fiberglass batts. This makes it slightly more difficult than fiberglass batts but comparable to blown in cellulose.

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. Blown fiberglass on the other hand is made up of very fine strands of glass and these tiny fibers are a carcinogen that can easily be inhaled into your lungs. In contrast to fiberglass insulation cellulose insulation does not trap air in between it s fibers to control heat. More consistent pricing from cellulose manufacturers than fiberglass.

Thus creating a more energy efficient home. Wet blown cellulose is also subject to similar contamination too. Making cellulose a better choice for homes in northern climates. Cellulose insulation is always blown in.

Loose fill or blown cellulose insulation is manufactured primarily from recycled newspapers a very benign product so it poses virtually no ongoing health risk.