Cellulose Insulation by Chris Zieminski & Nathaniel Hoag

Cellulose is made of eighty to eighty-five percent recycled wood fiber (mostly from newsprint), as well as fifteen to twenty percent borax and boric acid. A fifteen hundred square foot home would recycle forty years worth of newsprint for an average individual. Cellulose insulation has the potential to offset 3.2 million tons of newsprint waste annually in America.

Embodied Energy Cellulose insulation = 0.48 GJ/m³ Fiberglass, rock wool, and plastic insulation may contain fifty to two hundred times more embodied energy than cellulose. (Woolley et. al., 1997) Embodied Energy

Cellulose Insulating Performance Average R-value of 3.7 per inch. Lasts for the lifetime of a building, provided it is kept away from moisture. Stops air infiltration. Increases fire resistance by twenty-two to fifty-five percent. Settling of cellulose leads to decreased R-values, but this can be averted with newer “stabilized” cellulose products. Decreases sound transmission through a wall.

How does fiberglass measure up to cellulose? University of Colorado built two identical structures. One was insulated with cellulose, one with fiberglass. Cellulose tightened the structure 36-38% better (blower door test). It also used 26.4% less energy to heat. Cellulose performed 38% better than fiberglass. Benefits increase with increased latitude. Exemplified in homes in UK, PA, KS, MA.

Health Impacts Cellulose is classified as a nuisance dust. Borax is considered an environmentally acceptable pesticide, and classified as having low, acute toxicity for mammals. Few health studies have been conducted due to the commonness of cellulose components According to the National Toxicology Program, fiberglass is “reasonably anticipated to be a carcinogen on humans.” Fiberglass disposal is an increasing environmental concern.

Conclusion Cellulose is times more expensive than fiberglass but more efficient and better for the environment. Information is essential.