What is mineral wool

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Mineral wool insulation is an insulator that is frequently used in the construction industry and piping industry. Mineral wool insulation is a poor thermal conductor, and it has excellent flame resistant properties. Mineral wool insulation is also used as an acoustic dampener. Mineral wool insulation may also be known as rock wool insulation, stone wool insulation, or slag wool insulation.

Mineral wool insulation is made from a mixture of stone and slag, which is why it is also called rock wool insulation, stone wool insulation or slag wool insulation. The stone or slag is heated in a furnace until it becomes molten. Then, in a process similar to manufacturing cotton candy, the molten rock or slag is spun until it cools in the formation of long, thin fibers. The fibers are then densely packed on top of each other.

Mineral wool insulation is used in buildings and structures for several reasons. First and foremost, mineral wool insulation does not conduct heat well.

This is important when trying to keep a building warmer or cooler than the outside environment. Since fires are always a concern for buildings, the fact that mineral wool lacks flammability makes it an excellent option as an insulator.

Also, mineral wool is an excellent acoustic dampener if noise is a concern when building a structure. Heat transfer is also reduced because the material acts as a physical barrier to radiative processes. Glass and stone mineral wool insulates by trapping and holding air still. It does not rely on injected gas that can leak and result in a deterioration in thermal performance.

Additionally, the structure of mineral wool - a mat of fibres which prevents the movement of air — coupled with its long-term stability, gives it an unique ability to combat noise pollution and promote safety by reducing the risk of fire. Mineral wool insulation is made from molten glass, stone or slag industrial waste that is spun into a fibre-like structure and which creates a combination of properties that no other insulation material can match.

There are two types of mineral wool product: glass wool insulation and stone wool insulation. Stone wool is made from volcanic rock, typically basalt and an increasing proportion of recycled material in the form of briquettes.