Builder, Dec. 5, 2016, by Lauren Shanesy.
http://www.builderonline.com/products/building-materials/insulating-homes-with-natural-sheeps-wool_o

"Wool has been keeping both sheep and humans warm for centuries. But now one company is using shorn sheep’s wool to give fiberglass and foam insulation a run for their money. Havelock Wool uses 100% natural wool sourced from New Zealand sheep to insulate homes and other buildings. Sheep grow wool in excess, so the renewable material is readily available and has a number of inherent, eco-friendly properties that make it a viable contender for building insulation."