A Beginner’s Guide to Insulation – Fire Safety

By Knauf Insulation
August 10, 2021

We want to feel safe in the buildings in which we live and work.

We all know that using insulation in a building can help to regulate its temperature and make it more energy-efficient, but how safe is the insulation in our homes and workplaces?

Does insulation contribute to fire safety?

It depends on which insulation materials you are using.

For a fire to grow, you need three elements:

  1. A heat source;
  2. Oxygen;
  3. Fuel.

In a building, the fuel is any kind of combustible material inside, such as furniture, carpets, curtains, and more. Choosing non-combustible insulation reduces the potential fuel content, offering the best performance when it comes to both Reaction to Fire and Fire Resistance.

Reaction to Fire is the material’s ability to contribute to the growth of a fire by acting as a fuel source and Fire Resistance is the material’s ability to resist fire for a given period to prevent its spread and maintain the structure’s integrity, allowing the safe exit of occupants in a fire’s fully developed stage.

What is a fire classification?

All insulation materials are given a Euroclass reaction to fire classification, which helps us to understand how much ‘fuel’ will be added to the building, as well as how a material will contribute to the development stages of a fire.​

The graph below shows how each classification contributes to a fire, and the common insulation materials that have these classifications.​


It is best to choose insulation with an A1 or A2-s1,d0 classification to ensure the highest levels of fire safety and to eliminate as much risk as possible. Materials that achieve A1 or A2-s1,d0 produce little or no smoke and no flaming droplets when exposed to fire.

How can we help?

As you can see in the graph, Glass and Rock Mineral Wool insulation is naturally non-combustible with the best A1 or A2-s1,d0 classification. This is without sacrificing high levels of thermal and acoustic performance, and contributing to better indoor air quality.

As they are manufactured from different raw materials, Glass and Rock Mineral Wool insulation perform slightly differently. You can use them interchangeably, however there are some applications where one will perform optimally.

Our non-combustible solutions help inhibit fire spread, maintain structural integrity and limit the spread of fire and smoke from one area to another, providing safe buildings for occupants.

If you have any questions regarding fire safety, get in touch with us today.