When confronted with potential fire threats, appropriate insulation can offer crucial protection, slowing down flame propagation and heat transfer. Thanks to technological advancements and heightened consciousness of fire safety standards, a variety of fire-retardant insulation choices are available.
Whether you're a property owner, builder, or just someone keen on fire safety, this blog is designed to provide you with essential insights into the various degrees of fire-rated insulation prevalent in the UK.
Fire-resistant insulation is paramount in safeguarding structures, and it's a vital aspect for homeowners, builders, and designers. Here's why fire-rated insulation holds significant relevance:
Fully fireproof insulation isn't achievable. The terms "fire-resistant" or "fire-retardant" are more precise, and understanding the distinction between them is essential:
Combustibility refers to a material's propensity to ignite because of fire or a chemical reaction. While a flammable substance can quickly ignite, a combustible one is harder to set alight and might not burn as vigorously. The British Standard outlines classifications for such products. For fire-resistant thermal insulation, you'd ideally seek products with an A1 or A2 rating. Products with lower ratings may, in extreme situations, aid in the spread of flames or even become ignited.
In England, the building regulations related to external wall insulation (EWI) and other building practices are laid out in the Building Regulations. Approved Document B (Fire safety) is particularly crucial given concerns about the flammability of some types of insulation, particularly after incidents like the Grenfell Tower fire. It offers guidelines on the fire performance of building materials, including external wall insulation systems.
Mineral wool, which includes both rockwool (derived from basalt) and slag wool (derived from steel mill slag), is inherently fire-resistant due to its mineral-based composition.
Mineral wool, unlike some other insulation materials, mineral wool doesn't typically need added fire-retardant chemicals, as it is naturally fire-resistant. This is a key advantage of mineral wool over some synthetic insulation materials.
Because of these properties, mineral wool is considered an excellent choice for fire safety in building applications, including external wall insulation. When used as part of a properly designed and installed insulation system, mineral wool can significantly enhance a building's overall fire resistance.
However, it's essential to ensure that any external wall insulation system adheres to local fire safety standards and regulations.
Foamed polystyrene, commonly known as Expanded Polystyrene (EPS), is inherently flammable. However, when used for external wall insulation, EPS often contains fire-retardant additives to help reduce the risk of fire spread.
Fire-Retardant EPS: Most EPS products used in construction, including external wall insulation, are treated with fire-retardant additives to reduce the material's flammability. This means the treated EPS is designed to resist ignition for longer than untreated EPS when exposed to a flame. Fire-retardant EPS will self-extinguish once the ignition source is removed, under controlled conditions.
It's important to note the following:
At PD Rendering, polyurethane foam used for external wall insulation is treated with fire-retardant additives to meet building regulations and safety standards. These standards aim to reduce the risk of fire spread across the external facade of a building.
Approved Document B provides guidance on fire safety for buildings in England, and it's crucial to select products that comply with these guidelines.
The fire-retardant coatings on the foam surface don't make the material non-combustible, but they can protect the underlying matrix against thermal degradation and suppress the fire spread without damaging its inherent mechanical properties.
Polyurethane has the peculiarity that when it comes into contact with the flame, instead of melting, it carbonises, protecting the core of the fire. This causes the structure to remain stable for some time.
For this reason, polyurethane systems are never the origin of a fire. The beginning must be a different one and the isolation, if achieved, will be based on the design of the structural element in which it is integrated, and the time that elapses as the fire develops. The design of the building is key when it comes to fire safety.
Always ensure that you work with specialists knowledgeable about fire safety regulations relevant to building and insulation.
Fire-rated insulation is paramount when improving the fire safety of buildings. In order to prevent the spread of flames, minimise smoke production, and protect tenants and property in case of a fire, the consideration of fire performance of insulation materials is crucial.
Before selecting the fire-rated insulation material, always ensure to consult with an experienced insulation company, review technical specifications, and adhere to local building regulations.
At PD Rendering, our fire safety experts and professionals can provide valuable guidance to ensure the chosen insulation materials meet the required fire ratings and are suitable for the specific application.
Bear in mind, that the information in this article is for general understanding and shouldn't be taken as professional guidance. For specific advice on fire-rated insulation, please get in touch with our fire safety experts.
