The Ultimate Guide to uPVC vs Composite Fire Rated Cladding

Selecting the appropriate cladding materials for your project, particularly fire rated cladding, is crucial for safeguarding your home or building against fire hazards. Whether you're a homeowner or a building contractor, understanding the fire ratings of various cladding options is crucial for making informed decisions. In this blog post, we will explain the fire ratings of uPVC and composite cladding materials. We'll also explore their properties, benefits, and drawbacks and examine how adopting fire rated cladding can enhance the safety and resilience of your structures.

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Fire-rated cladding refers to exterior wall coverings that have been rigorously tested and classified for their ability to resist fire. This classification provides crucial information about the material's combustibility, thermal reaction, and flame-spread prevention capabilities.

"Combustibility" indicates how easily a material can catch fire and sustain combustion. Testing typically involves exposure to high temperatures and flame directness to evaluate these properties.

Understanding these ratings is critical when installing fire rated cladding on residential or commercial properties. It helps ensure the chosen materials meet safety standards and building codes, thereby protecting the building's occupants. It is essential to always consult fire safety experts and adhere to local regulations when selecting and installing cladding materials.

Fire Rated Cladding Ratings: Understanding The New System

The European Reaction to Fire classification system (Euroclass) determines fire ratings for cladding materials in the UK and across Europe. This system evaluates building materials based on how they react to fire, providing a standardised classification that ranges from A1 to F, with A1 being non-combustible and F being highly flammable. Non-combustible cladding is classified as A1 in this system.

Before adopting the Euroclass system, the UK used the "Class 0 Fire Rating" system to classify building materials based on their fire performance. This rating was part of the British Standards (BS 476) and focused on two primary tests: the 'surface spread of flame' test and the 'fire propagation' test. To achieve a Class 0 fire resistance rating, a material had to exhibit limited flame spread in both tests and minimal contribution to fire growth.

Although Class 0 provided a useful benchmark for assessing fire safety, it did not account for factors like smoke production or flaming droplets, which the more comprehensive Euroclass system includes.

When looking for fire rated cladding it's important to understand the classifications. These consider factors such as ignitability, flame spread, heat release, smoke production, and the potential to emit flaming droplets and particles. Here's a quick breakdown:

A1 and A2: Non-combustible materials with no contribution to fire.
B: Limited combustibility, similar to the old Class O system.
C to F: Increasing levels of combustibility, with F being the most flammable.

The Importance of Smoke and Flaming Droplets Ratings

In addition to the primary classification of fire rated cladding above, the Euroclass system includes ratings for smoke emission (denoted by 'S') and flaming droplets/particles (denoted by 'D'). These ratings help determine the overall safety of the cladding material in a fire scenario.

Smoke Rating (s1, s2, s3):

s1: Low smoke production.
s2: Moderate smoke production.
s3: High smoke production.

The letter "S" in the Euroclass fire rating refers to the emission of smoke during the first 10 minutes of exposure to fire. The classifications range from s1 to s3, with s1 indicating very little or no smoke production and s3 indicating substantial smoke production.

Flaming Droplets Rating (d0, d1, d2):

d0: No flaming droplets or particles.
d1: Limited flaming droplets or particles.
d2: Significant flaming droplets or particles.

The letter "D" relates to releasing flaming droplets and particles. The classifications range from d0 to d2, with d0 indicating no flaming droplets or particles and d2 indicating a significant release of flaming droplets and particles.

uPVC Cladding Fire Ratings

uPVC (unplasticised polyvinyl chloride) is a popular cladding material made from chlorine and ethylene derived from natural gas or petroleum. While uPVC cladding is known for its durability and low maintenance, it has some fire-related drawbacks.

Fire Rating: When it comes to uPVC fire rated cladding it typically has a Euroclass rating of C or D, indicating limited to medium combustibility.
Combustion Behaviour: In a fire, uPVC cladding warps, melts, and chars. It can fall away from the building, exposing underlying materials to direct flames.
Environmental Impact: Burning uPVC releases toxic dioxins, which are hazardous to humans and the environment.

When choosing fire rated cladding it’s important to note that the burning of uPVC can also release hazardous chemicals into the environment, making it a less eco-friendly option. This factor is especially important for those prioritising environmental sustainability in their building projects.

Aluminium Cladding Fire Ratings

Aluminium cladding is an excellent choice for fire-rated cladding, achieving an A-rating in the Euroclass system due to its non-combustible properties. This makes it particularly suitable for high-rise buildings and structures where stringent fire safety regulations are in place. While not always necessary for residential homes, aluminium cladding provides unparalleled fire resistance, making it the ideal option for those prioritising safety.

In addition to its fire safety advantages, aluminium cladding is durable, resistant to corrosion, and recyclable, although its production can be energy-intensive. Its sleek, modern appearance and low maintenance requirements make it a popular choice in architectural applications, especially in environments requiring the highest fire safety standards.

Composite Fire Rated Cladding

Composite cladding, such as

Hyperion Sentinel, is made from recycled wood and high-density polyethylene. This fire resistant cladding is designed to offer both aesthetic appeal and enhanced fire resistance. This fire resistant composite cladding external solution, has been specially treated with fire-retardant additives, earning it a Euroclass rating of B s2-d0. This rating indicates a very limited contribution to fire, no flashover, moderate smoke production, and no flaming droplets or particles.

Composite fire rated cladding offers superior fire resistance compared to uPVC while aligning with sustainability objectives. With a higher fire resistance rating and construction from recycled materials, it stands as an eco-friendly choice for environmentally conscious builders and homeowners. This type of cladding enhances building safety by better withstanding high temperatures, providing greater protection in the event of a fire.

Furthermore, by utilising recycled materials, composite fire-rated cladding helps reduce waste and conserve natural resources, making it an excellent option for those committed to minimising their environmental impact.

1. Fire Rated Cladding Has Enhanced Fire Resistance

When comparing the fire resistance of uPVC and composite cladding, composite cladding clearly comes out on top. With a lower Euroclass fire rating of B versus C/D, composite cladding is less combustible and flammable, making it the safer choice for your building project.

2. Complies With Regulations for Fire Rated Cladding

In response to tragic events such as the

Grenfell Tower fire, the UK has implemented stricter regulations for fireproof cladding materials. Recent

legislative changes in the UK require that exterior cladding panels on residential buildings, schools, care homes, and hospitals over 18 metres must have a fire rating of Euroclass A.

While office blocks and hotels are exempt from this regulation, and buildings under 18 metres are not affected, choosing a higher fire rated cladding like composite can still offer peace of mind and enhanced safety.

Adhering to fire safety regulations is crucial for avoiding legal complications and ensuring the longevity of your property. By selecting cladding with the appropriate fire rating classification in the UK, you can stay compliant with the latest building codes.

3. Fire Rated Cladding Enhances Safety

Fire-rated cladding is essential for enhancing the overall safety of a building by providing an additional layer of protection against fire hazards. By choosing materials that are designed to withstand high temperatures, you not only safeguard the occupants but also help to minimise the risk of extensive property damage, ensuring your building remains secure in the event of a fire.

4. Peace of Mind

Installing fire rated cladding provides the reassurance that your building is well-protected against fire hazards. This proactive measure not only contributes to a safer living and working environment but also demonstrates a strong commitment to the well-being of everyone inside. With fire-rated cladding, you can feel confident that you've taken the necessary steps to safeguard your property and its occupants.

In the debate between uPVC cladding and composite cladding, composite cladding stands out as the superior option for fire resistance, environmental sustainability, and overall safety. Whether you're enhancing your home's exterior or overseeing a large construction project, knowing the fire ratings of your cladding materials is crucial to making an informed and responsible choice.

Ready to take the next step? Explore the benefits of Hyperion Sentinel composite cladding and ensure your next project meets the highest safety and sustainability standards. Besides fire rated cladding, EnviroBuild also offers eco-fri

decking,

fencing,

paving,

subframe,

flooring,

garden furniture and

commercial solutions.

Contact EnviroBuild's team of experts today for personalised advice and to learn more about our range of fire rated cladding options.

Please Note: Regarding load-bearing for fire resistance (BS 476-21), external wall cladding cannot be tested separately from the fire rating of the attached wall. Always refer to the wall’s fire rating, as EnviroBuild Sentinel cladding does not alter this.

DISCLAIMER: Customers are responsible for determining the suitability of Hyperion Cladding for their specific private or commercial installations. They should also consult with local building control to meet the fire classification project requirements when choosing fire rated cladding.