Mineral wool, also known as slag wool and rock wool, is a fibrous material made from molten rock, man-made or natural minerals and metal oxides. It is a great alternative to fiberglass and is more commonly used in Canada, Australia, New Zealand and Europe than the US. It is available as batts, blankets or loose-fill.

Manufacturing process of mineral wool
Mineral wool is produced by spinning molten rock in a furnace at temperatures nearing 1600°C. A stream of hot air or steam is blown into the spinning mass. The result is a fine formation of intertwined fibers of 6-10 micrometers in diameter. Starch or oil may be used as a binder to minimize dusting in the mineral wool.

Properties and uses of mineral wool
Mineral wool has many useful properties that make it a heavily used product in various applications:

• Heat insulator: Mineral wool when rolled into sheets can partition air effectively, making it an excellent heat insulator.
• Sound absorber: Due to its highly fibrous structure, sound is attenuated, making it an excellent sound proofing material.
• Thermal resistance: Mineral wool is non-combustible and has a melting point of 1800-2000°F, making it suitable for fire proofing indoor facilities. Typical applications of mineral wool include:

           - pipe insulation
           - residential and commercial facilities insulation
           - ship insulation
           - mobile home fire protection
           - fire proofing spray and ceiling tiling
           - cooking appliances
           - packing material in firestops

• Energy conserver: The insulating properties of mineral wool make it a good constituent in the development of energy efficient buildings – homes, offices, commercial buildings, manufacturing plants, and so on.
• Fibrous structure: Its fibrous structure makes it a good filtering medium. Rock and slag wool can also hold large quantities of water and air to support root growth and nutrient retention in horticultural projects. Mineral wool products are conditioned to get a suitable pH for plant growth.
• Reinforcing material: Mineral wool is used as a reinforcing material in the manufacture of fractioning materials, brake pads, gaskets, and plastics in the automotive industry.

Mineral wool price
Mineral wool and fiberglass are both candidates for insulation products. However, mineral wool is denser and provides better heat and sound insulation. Also, it does not lose these properties when it gets wet. Mineral wool has unmatched fire resistance. However, as mineral wool is less commonly available than fiberglass, it is costlier and variably priced across states.

Studies reveal that mineral wool is a safe product to be used indoors. In fact, as it insulates and controls temperature and condensation, it improves the indoor environment. However, direct contact should be avoided as airborne mineral wool dust can cause skin, eye, nose, and throat irritation.