There are few instances in which cellulose insulation is not the best option. Not only is it almost entirely recycled product with very little embodied energy and no toxicity to humans, but it has high resistance to fire (can be used as a firestop), a high sound-attenuating coefficient, is toxic to common household insect pests and an irritant to rodents, is relatively impervious to air movement but very permeable to moisture (breathes) and so hygroscopic that it will protect wood framing from saturation, mold and rot, is not corrosive to metal fasteners (if treated with borate and not ammonium sulfate), has the highest R per inch of any of the fibrous insulations (which increases with higher or lower than room temperatures), and not only won't settle if installed at proper densities but also will expand as wood shrinks or moves to keep all cavities full.

--- On Thu, 12/11/08, Suzy Hodgson <[log in to unmask]> wrote:
cellulose insulation made with recycled paper is a good green option with performance - high R value  and low ghg emissions