Debunking The Myths About Fire Safety And EPS

EPS (expanded or extruded polystyrene) has taken its place as one of the most popular forms of external wall insulation. In the wake of Grenfell and the Building Safety Bill, insulating materials have received a particularly high level of scrutiny, with the replacement of combustible insulation a national priority. 

As the spotlight intensifies on safer building practices and increasing energy efficiency throughout UK residences, especially on the journey to Net Zero, it is important to fully understand the properties and principles of EWI, in particular, the popular EPS.

Although it is sought after, there are still detractors who question the abilities of EPS as a true alternative to more expensive options such as mineral wool. Here we address Soltherm’s top five most common misconceptions about EPS, its properties and suitability for fire safety and energy efficiency. 

“EPS is not Durable”

EPS has excellent impact absorption qualities, offering much needed support to surrounding outer building layers and joints. When installed correctly, it serves as a durable barrier that will not attract bacteria or corrosion. While UV does have the potential to discolor EPS, there have been no findings to determine a degradation in strength and impact resistance.

“EPS is flammable”

A popular misconception is that EPS is combustible and should therefore not be used as insulating material. While the base material that makes up EPS is in itself flammable, today it is made with fire retardant additives (FRAs) to enable specifiers to use EPS and enjoy its cost effectiveness and efficiency, without compromising on safety.

The Ultimate FSC system features a patented composite Grey EPS insulation board demonstrating exceptional fire performance against conventional EPS systems:

“EPS is too absorbent”

EPS is highly resistant to moisture and at the same time, has minimal leaching potential. While some tests involving submerged EPS reported a weight increase of around 1%, it does not lose its durability or insulating properties.

“EPS is not environmentally friendly”

EPS as an insulating material is fundamentally environmentally friendly, reducing energy consumption throughout the protected building. As a manufactured material, it is an organic petroleum-based material that contains no CFC’s or HCFC’s. 

“EPS is not recyclable”

EPS is 100% recyclable. Specialist foam product processing plants convert ground EPS and EPS resin into many useful household and industrial products. Many manufacturers also offer this service.

Soltherm offer a range of thermal insulation up to A1 fire rated, increasing U-Value to a building's fabric while decreasing heat loss throughout the structure. This includes a specialist engineered EPS, offering outstanding thermal performance without sacrificing safety or energy efficiency.

For more information about our insulation range including EPS, contact us using the details below.

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Soltherm manufacture EWI systems for new, durable, rock-solid and crack-resistant façades with 75 years service life. With an ongoing commitment to innovation and improvement, Soltherm have produced a fully certified A1 fire rated system, using fire safe technology. Read more to view our full range of systems.