Origin & Properties of Stone Wool
Stone wool (mineral wool) was discovered on the islands of Hawaii at the beginning of the century. It occurs there naturally as a byproduct of volcanic activity. In its manufactured state, stone wool combines the power of rock with the characteristics of typical insulation wool. In addition, thanks to its non-directional fiber orientation, it also exhibits some unique and valuable characteristics.
Stone wool is an excellent insulator and a vital component of an energy efficient building. In fact Insulation saves 12 times as much energy per pound in its first year in place as the energy used to produce it. [http://www.naima.org/pages/benefits/environ/effic.html]
The non-directional fiber orientation of the stone wool helps the absorption of acoustic waves and can reduce the intensity and propagation of noise.
Stone wool can withstand temperatures up to 2150º F (1177º C). Consequently it does not contribute either to the development and spread of fire or the release of toxic gases.
Stone wool is water repellent yet vapor permeable. This means that the insulation cannot absorb water so the R-value is not affected. Additionally it is completely resistant to rot, mildew, mold and bacterial growth, contributing to a safer indoor environment.
Stone wool retains its characteristics unaltered over time. It undergoes only minimal changes in size or performance to the changing conditions of temperature and humidity.