Production

• For each tonne of CO₂ generated in the manufacturing process of mineral wool, about 200 tonnes of CO₂ are saved by its thermal insulation properties over a 50-year period.  Very high levels of energy and emissions are saved during a product's lifetime compared to the energy input required to make it.
• Producing mineral wool requires only half the energy needed to manufacture other types of insulation.
• There has been a steady decrease in energy inputs and emissions during production over time.
• Increasing amounts of recycled materials are used in the manufacture of mineral wool inputs.

Within the glass wool sector a major contributor to energy savings in recent years has been the use of glass from recycling.  Depending on the quality and availability of local supplies recycled glass now makes up 30% to 60% of the raw material input. In some plants this is as high as 80%.

Transport

The high compression ratio and elasticity of mineral wool means that the products can often be packed to up to half of their original volume.   Fewer lorries are required to transport it, thus reducing environmental impact of transportation.

Life cycle analysis of a mineral wool product

The diagram shows the typical environmental impact of a mineral wool product over its lifetime in terms of energy use and greenhouse gas emissions.  It can be seen that the life cycle approach reveals the tremendous environmental benefits of mineral wool.

Waste

Owing to improving technology, most of the waste products are recycled back into the production process as well as using waste from building sites or demolition works as an input to replace raw materials.  The graph below shows the declining levels of waste sent to landfills from the production process.

Water used in the process is generally in a closed circuit system.  This has the twofold advantage of reducing fresh water consumption and avoiding the discharge of dirty or polluted water.