Sheep’s wool insulation is becoming a popular commodity in the green building industry. It is marketed as being eco-friendly, creating good indoor air quality, and being safe and easy to install. Producers claim the product “requires less than 15% of the energy needed to produce fiberglass insulation.” The Healthy House Institute claims it has an R-value of 3.5 to 3.8 per inch of material thickness—higher than fiberglass, cellulose, or mineral wool.
The British sheep wool industry produces over 2.1 million tons of wool a year. The insulation is also catching on in Australia, which produces 55% of the world’s raw and processed wool.
Black Mountain Insulation Ltd. (see their logo, above at right) was established in England in 2007. Its sheep’s wool product, Natuwool, according to Black Mountain, is “ideally suited to timber frame structures.” It recommends the product for insulation of lofts, rafters, walls, and floors. “Sheep wool fibers draw out moisture,” its website claims. Natuwool is made of 90% wool content and achieves a fire performance rating of Euro Class E. Wool insulation “has a unique ability to absorb noxious gases emitted from some building products (e.g., formaldehyde).”