Rock Wool

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Rock Wool

What is Rock Wool Insulation? 

Rock Wool Insulation is a stone-based and sourced from the lava found in volcanic rocks. Rock Insulation is a medium density slab that is used as a barrier for several purposes: 

  • Preventing water from transferring from the outside wall to the internal wall – Water easily penetrates lighter density rock wool; however, the insulation can be engineered to prevent the ingress of moisture. 
  • Offering thermal insulation – Rock Wool Insulation works by trapping air in small cells meaning that they cannot naturally transfer the heat. 
  • Providing insulation against fire - Rock Wall is an A1 non-combustible product to European Standards, meaning that it will not burn in a building fire. We recommend choosing high-density rock wool for the greatest resistance to fire. 
  • Reducing sound – The insulation reduces noise by forming a system that is like the suspension system that your car has. 

Rock Wool contains at least 95% stone wool, however despite the name, it is not as heavy as it sounds and one person should be able to fit the insulation on their own. 

How is Rock Wool Insulation be made? 

The molten rock used to create Rock Wool is melted down in a furnace with an average temperature of 1600°C, with the idea of mimicking what occurs inside a volcano. 

The resulting lava is spun in a process that is very similar to the one used to turn melted sugar into Candy Floss, creating the fluffy consistency of wool. The Rock Wool is then shaped, based on the application that the wool is to be used for. 

Where can Rock Wool Insulation be used? 

Rock Wool Insulation is most commonly used in five different areas: 

  • Cavity Walls – When two walls of brick, blocks, concrete or stonework are built-up running parallel with each other, and with a hollow area in the middle; this is a cavity wall. Whilst they commonly used to offer water resistance, they are now also used for insulation. 
  • Floors – Flooring is most likely to need acoustic as well as thermal insulation, as it helps to soften the sound of footsteps heard on lower floors from the ones above. It is particularly useful in apartment buildings, to help prevent sounds travelling. The Rock Wall Insulation is typically installed beneath chipboard, floor screeds or concrete slabs. 
  • External Walls (EWI) – The outer wall of the building needs to be fire, compression, and water resistant so that other types of additional barriers are not needed. External Wall Insulations are generally designed to thermally upgrade an existing building, which is either difficult to treat or fall within the carbon emission reduction target system. It is estimated that around 35% of heat loss occurs through the walls. 
  • Partitions – These are internal walls that separate rooms from each other and require insulation for sound reduction as well as thermal insulation. 
  • Lofts – Around 25% of heat is lost through the roof of your home, especially if your loft is unused or is only used for storage. Loft insulation is typically inserted into the space between the inside wall and the outer brick, preventing air from circulating and thus reducing heat loss.