Sheep wool is a good thermal insulator and is also being effective as a sound insulator, especially on airborne sounds. It is a natural insulator, healthy and environmentally friendly. Wool undergoes different stages after it’s been sheared: soaking, degreasing, rinsing, treatment. It is treated with boron salt as protection against fire, mold and insects. It also undergoes a special treatment against mites, which feed on the keratin found in wool. Die-hard environmentalists have a preference for raw wool, unwashed and naturally protected by grease. They will tell you that the strong smell of unwashed wool disappears with time.

Sheep wool comes in panels, rolls or felt. Its great ability to absorb water makes it unsuitable for wet areas and walls, and ground. It is generally preferred for the roof and attics.