Why don't more builders use cellulose insulation in attics? One obvious reason is that cellulose is generally less available than loose-fill fiberglass. Also, it's kind of dull looking compared to fluffy pink or silky white fiberglass. (After all, it is just a pile of gray-colored ground-up newspaper.) But cellulose has higher R-value per inch, better resistance to air leakage, and typically a lower price than fiberglass. Although I don't think either material is necessarily the "insulation of choice," I suspect that many builders are hesitant to use cellulose because of misinformation or unfounded concerns over material properties such as flammability, corrosiveness, and settling. The most fantastic objection to cellulose I've ever heard was at a builders' workshop in Wisconsin last winter. One
