Cellulose Vs Fiberglass Blown In Attic

Cellulose has an r value of 3 5 3 7 per inch where fiberglass has around 2 1 2 7 r per inch.

Cellulose vs fiberglass blown in attic.

Rather than trying to meticulously lay fiberglass insulation over the attic homeowners and builders can simply blow cellulose insulation throughout the attic. Blown cellulose is typically the preferred choice of insulation for attics. 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. 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.

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. Or 7 inches of cellulose. This is called wind washing. 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. Fiberglass batts however are less expensive costing on average 0 30 to 0 40 a square foot for 6 inches of insulation. Wet blown cellulose is also subject to similar contamination too. Cellulose insulation blown in attic r 3 6 r3 7 cellulose insulation blown in wall r 3 8 r3 9 both fiberglass and cellulose insulation can be installed to completely fill the space inside of wall floor or ceiling cavity.

Compared to fiberglass cellulose is a superb air blocker. You can get to the same place with either material. Dry blown cellulose will characteristically settle and sag in place reducing its r value. Loose fill or blown cellulose insulation is manufactured primarily from recycled newspapers a very benign product so it poses virtually no ongoing health risk.

As a recycled paper product cellulose is prone to absorb moisture that can cause wood rot and mould. Loose fill blown fiberglass insulation has another slight problem. Blown in cellulose homeowner benefits. As the temperature difference between the living space and attic increases the r value of blown fiberglass diminishes.

This phenomena seems to occur as a result of thermal convection. Higher r value per inch. 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. Cellulose attic insulation read more.