National Fiber has been producing Cel-Pak Cellulose Insulation in Belchertown MA since 1978.  Using primarily over-issue newsprint, the finest, cleanest newsprint available, free from the trash and debris. Cel-Pak is made from 82% +/- recycled paper and 100% Borate (a natural mineral) to provide fire, insect, and mold resistance while providing the exceptional moisture, thermal and sound barriers. In addition to making a quality product, National Fiber also offers contractor training (on-site facility), machine sales, and technical assistance to their customers.