It also comes in a perforated plastic sleeve to assist in handling. There are also several variations of loose fiberglass intended for use with insulation blowing machines. Some products claim higher recycled material content, or some other marketing theme, that can make them stand out from the competition. However, they all provide similar thermal performance. Tests have shown that walls insulated with a BIB system are significantly better filled than with other forms of fiberglass insulation, such as batts.
Most mineral wool made in the United States is actually slag wool.
Mineral wool does not use additional chemicals to make it fire resistant. Recently, a Canadian company began producing a softer, batt type mineral product. This batting is denser, fits standard wall cavities tighter, and is somewhat less prone to air convection thermal losses. Than standard fiberglass batt products. The fibers are then formed into batt insulation similar to high-density fiberglass, and then treated with a fire retardant.