Loose-Fill Cellulose Insulation
Cellulose insulation is a type of wood- or paper-based product. It is used to fill empty spaces in the structural part of a house to slow down the transmission of heat or cold. Cellulose insulation is thick, dense, and clumpy, with a consistency much like down feathers. The chief value of this shape and size is that the insulation can fit in enclosed areas (such as walls) and can conform around obstructions such as wires and ducts (found both in walls and in attics).
Cellulose insulation technically can come from any cellular plant source, such as corncobs or sisal. But commercial cellulose insulations are generally derived from wood, and more specifically from paper: recycled newspapers, cardboard, office paper, and other common waste paper products. For this reason, cellulose insulation is considered an eco-friendly home product.