Cellulose Insulation is made from recycled wood fiber, primarily newsprint, that is shredded and pulverized into small, fibrous particles that pack tightly into closed building cavities, inhibiting airflow. This provides a thermal resistance of R-3.6 to R-3.8 per inch
Fiberglass (or fiber glass)—which consists of extremely fine glass fibers—is one of the most commonly used insulation materials. It's used in two different insulation forms: blanket (batts and rolls) and loose-fill
Polyurethane is a closed-cell foam insulation material that contains a low-conductivity gas in its cells. The high thermal resistance of the gas gives polyurethane insulation materials an R-value typically around R-7 to R-8 per inch