Fiberglass Insulation Vs Cellulose Insulation For Attic

Air moving through a vented attic deposits dirt and dust into fiberglass batts.

Fiberglass insulation vs cellulose insulation for attic. Fiberglass is a suspected carcinogen. Thus creating a more energy efficient home. Cellulose insulation is also chemically treated to resist fire insects and mold. This allows the insulation to get into the small pockets and crevices that fiberglass wouldn t be able to.

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. It has a better resistance to air flow and prevents the upward movement of air caused by temperature differences. This is called wind washing. Or 7 inches of cellulose.

Because it is denser than fiberglass cellulose is much more resistant to wind washing. You can get to the same place with either material. Cellulose insulation is considered green as it is made from recycled newspaper and requires less energy to manufacture than fiberglass insulation. Cellulose provides better sound insulation than fiberglass i e homes are less noisy with it.

Many fiberglass installers fluff the fiber with extra air so you don t get as much insulation as you re supposed to. Unless you opt for spray foam then the insulation choices normally come down to cellulose and fibreglass.