Cellulose insulation is a loose-fill or blown material composed primarily of recycled paper fibers treated with fire retardants and anti-settling agents. It achieves R-values of R-3.2 to R-3.8 per inch using up to 85 percent post-consumer waste content, providing excellent environmental benefits. Its hygroscopic properties allow moderate moisture absorption without performance loss, requiring proper vapor management in design.
Performance Characteristics
Blown cellulose provides uniform coverage in irregular cavities, attics, and wall cavities where settling is minimized through proper density control at 1.4 to 1.6 pounds per cubic foot. Fire retardants maintain Class C or better flame spread ratings when installed to code specifications. Cellulose demonstrates superior air-sealing properties compared to fiberglass batts due to its dense packing and hygroscopic behavior that stabilizes with seasonal moisture fluctuation.
Installation Considerations
Professional blown-in application requires calibrated equipment for density verification and proper settling rates. Moisture management requires either interior vapor barriers or careful attention to drying potential in assembly design. Cellulose suits unvented attics and cathedral ceilings when combined with proper venting or interior vapor permeability specifications, delivering cost-effective R-value while diverting waste from landfills.