We all know that external wall insulation (EWI) is a fantastic way to insulate your home and save money on your energy bills. Today, we’re going to highlight the benefits of Rockwool, and why you should consider using it at the centre of your insulation system.

What is Rockwool? How is it produced?

Rockwool, also known as mineral wool, is very similar to fibreglass; although while fibreglass is made up of thousands of glass fibres, rock wool is made of molten volcanic rocks.

How is that possible?

The volcanic rock is heated in a furnace to about 3,000 degrees Centigrade, until it melts into a liquid. The lava is then exposed to a high-pressure jet of air or steam, and then spun at super-high speed into long fibre strands (like that of cotton candy). The strands are then compressed into thick, dense mats, which are then cut into conveniently-sized boards to be used as insulation.

What are the unique characteristics that make Rockwool an excellent insulation material?

  • It is made from a natural, sustainable material
  • It retains heat well and traps air, which slows the transfer of heat
  • It is non-combustible and fire resistant to about 1,400 degrees
  • It is highly water-repellent
  • It has excellent sound-deadening properties
  • It doesn’t degrade over time, so has great long-term performance
  • It is breathable, meaning it allows moisture to escape (deterrings mold and mildew)

Why use Rockwool in your EWI system?

So lets take a look at why the unique characteristics of Rockwool make it such as good choice to use in systems

  • Unrivaled fire protection
  • Rockwool is non-combustible. No other insulation material can match its fire resilience qualities. Rockwool will improve the fire resistance of any building.
  • Superior Soundproofing
    Our rockwool is an excellent sound isolating insulation material as it traps sound waves and dampens vibrations. This means you can have a warmer and quieter home.
  • Insulation to last several lifetimes.
    Rock wool is made up of rock. Rock is one of if not the most durable natural material around.  It is water repellant and vapor permeable, resistant to rot and mold and lasts for ages.  That means your rockwool insulation won’t shrink, it won’t move, and it won’t crumble.
  • Environmentally friendly and the sustainable option
    Rockwool is the sustainable choice. Its production is environmentally friendly and typically contains up to 75 percent recycled content. Using rockwool allows you to create a sustainable building and cut down your carbon footprint.
  • Specially designed for external wall insulation. Here at EWI Store our Rockwool has be designed and crafted and designed to the best insulation material for EWI as it uses the patented Dual Density technology to provide a high density top surface to a lower density subsurface. The lower density will accommodate slight imperfections in the fabric of the building and the higher density top layer is the ideal surface for the application of renders.

Why buy Rockwool from EWI Store?

Here at EWI Store, our Rockwool is specially designed and crafted to be the best insulation material for EWI. It uses the patented Dual Density technology to provide a high density top surface with a lower density subsurface. The lower density will accommodate slight imperfections in the fabric of the building, and the higher density top layer is the ideal surface for the application of renders.

  • Our Rockwool dual density boards are 1200 x 600mm and are sold in packs (normally 2 or 4 boards depending on thickness).
  • The Rockwool EWI insulation is available in 23 different thicknesses from 30mm up to 250mm and every 10mm increment in between.
  • The thermal efficiency (lambda) of the dual density boards is 0.036 W/m.k

For more information on our dual density Rockwool boards please download the datasheet by click on the button below.

Download technical information