Does Aluminum Burn? A1 Fire Retardancy Standards for Facades

Fire Safety in Facades: Does Aluminium Burn? A1 Class Non-Combustibility Standards

 

1. The Post-Grenfell Facade Safety Paradigm

In high-rise buildings, facade systems are among the most critical components regarding fire safety. Tragic events like the Grenfell Tower fire in London have painfully highlighted the vital importance of the combustibility properties of cladding materials. Following these events, building regulations globally have been updated, strictly prohibiting the use of combustible materials on buildings exceeding specific heights. In this article, we analyze aluminium's behavior under fire, international fire classification standards (EN 13501-1), and Mertcan Metal's A1 class solutions for safe facade design.

2. Thermal Properties and Non-Combustibility of Aluminium

There is a common misconception confusing melting with burning. By nature, aluminium is not a combustible material.

• Melting Point: Pure aluminium melts at approximately 660°C (transition from solid to liquid phase).
• Non-Combustibility: Aluminium does not ignite, does not spread flame, and does not sustain combustion. Once the heat source is removed, aluminium does not continue to burn.
• Gas Emission: The majority of fire casualties result from smoke and toxic gas inhalation. Aluminium (and mineral-filled composites) does not emit toxic fumes or dense smoke during a fire.

3. EN 13501-1 Fire Classification and Meanings

In the EU and many other regions, the "Reaction to Fire" of building materials is classified according to the TS EN 13501-1 standard. This coding system consists of three main parameters:

1. Reaction to Fire Class:
• A1: Non-combustible. No contribution to fire. (e.g., Solid Aluminium Sheet, Natural Stone, Concrete).
• A2: Limited Combustibility. Very low fire load. (e.g., Mineral-filled FR composite panels).
• B, C, D, E: Combustible classes. (e.g., Standard polyethylene-filled composite panels, wood).
• F: Not tested/determined.
2. Smoke Emission (s):
• s1: Lowest smoke emission (None or very little).
• s2: Moderate smoke.
• s3: High smoke production.
3. Flaming Droplets (d):
• d0: No flaming droplets.
• d1: Slow burning droplets.
• d2: Continuous flaming droplets.

Aluminium's Position: Solid aluminium profiles and sheets with no organic coating (or very thin <25 microns) are Class A1 materials. They do not burn, do not emit smoke (s1), and do not produce droplets (d0). This represents the pinnacle of fire safety.

4. Risky vs. Safe Choices in Facade Cladding

Aluminium Composite Panels (ACP/ACM), frequently used in facades, are classified based on the core material between the two aluminium sheets, creating massive risk differences:

• Polyethylene (LDPE) Filled Panels: Contain a petroleum-based black plastic core. In a fire, this core ignites, melts, and rapidly spreads flames to the top of the building via the "Chimney Effect." These are typically Class B or worse and are banned on high-rise buildings.
• Mineral Filled (FR - Fire Retardant) Panels: Contain a high percentage of non-combustible minerals (aluminium hydroxide, etc.). Classified as A2-s1, d0, they are safe for high-rise use.
• Full Aluminium Core Panels: Next-generation panels using corrugated aluminium sheets instead of a filler. These are Class A1 and provide the highest level of safety.

5. Conclusion: Why Choose Aluminium?

The greatest danger in facade fires is the vertical spread of flames between floors. A1 class aluminium profiles and sheets act as a natural barrier preventing this spread. Furthermore, thanks to their d0 (no droplets) property, they do not create the risk of molten material falling and endangering firefighters or starting secondary fires on lower levels. At Mertcan Metal, we view the use of A1 class aluminium facade systems—especially in high-rises, hospitals, and public buildings—not just as an aesthetic choice, but as a mandatory life-safety requirement.