What is mineral wool insulation?

Mineral wool is a non-metallic inorganic material manufactured from a carefully controlled mix of raw materials like stone and glass. Mineral wool is also known as mineral fiber, mineral cotton, mineral fibre, man-made mineral fibre (MMMF), and man-made vitreous fiber (MMVF).

Mineral wool is one of the most common insulating material manufactured and is used in buildings across the world. Mineral wool is extremely lightweight and flexible and holds in place between timber, metal frames and rafters without the need for additional fixings.

Specific mineral wool products are stone wool and slag wool. Europe also includes glass wool which, together with ceramic fiber, are completely man-made fibers.

Is glass mineral wool fireproof? 

Mineral wool insulation is an ideal fireproof material as it is non-combustible. Mineral wool will not burn until temperatures reach beyond 1,800°F (1,000°C). The insulation actually performs as a fire barrier, slowing down house fires and giving the fire services more time to get things under control.

How is mineral wool insulation made?

Mineral wool contributes to eight main areas in sustainable building. Mineral wool is made from a recycled smelting slag which is the main reason it is eco-friendly. 

Does mineral wool insulation need a vapour barrier?

Mineral wool insulation is open vapour permeable in nature, which states that moisture particles can find a way effectively from one side to the other through the material. 

Where is glass wool insulation used?

Mineral wool is a widely employable product that is used for:

• Insulating walls 

• Insulation of cavity walls and exterior walls

• Thermal and acoustic insulation of partition walls and storey floors

• Insulation of attic floors

• Insulation of pitched roofs and flat roofs

• Several industrial applications (insulation of machines, air conditioner, etc.)

Benefits of mineral wool insulation

Excellent Insulators

Though the individual fibers conduct heat very well when pressed into rolls and sheets, their ability to partition air makes them excellent insulators and sound absorbers. The fire resistance of fiberglass, stone wool, and ceramic fibers makes them common building materials when passive fire protection is required, being used as spray fireproofing, in stud cavities in drywall assemblies and as packing materials in firestops.

Thermal Insulation

The thermal performance of mineral wool is mainly due to prevention of convection by the entrapment of air in the material’s open-cell, woolly matrix. Conduction is reduced because there is very little solid material to provide pathways and the trapped, static air has low thermal conductivity. Heat transfer is also reduced as 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.

Acoustic Insulation

Porous materials such as mineral wool work to control and reduce noise by allowing air movement into the fabric of the material. The fluctuations of air molecules - which form sound waves - move into the body of the mineral wool, where friction between the air particles and the material’s narrow airways cause sound energy to be dissipated as heat.

Advantages of  mineral wool insulation

Naturally moisture-resistant

Same thermal protection when wet

Excellent soundproofing qualities

Quite Cheap 

Extremely fire retardant – up to 1,000°C

Minimal ecological footprint

The product is completely recyclable (new wool could be made with it)

Multiple application areas

Disadvantages of mineral wool insulation

Protective gear must be worn when installing mineral wool insulation: the tiny slivers will lodge in the skin and are small enough to be inhaled.

Inhaled slivers of mineral wool irritate the alveoli and can cause lung disease.