Why BS EN ISO 1716 is Essential for Fire Safety in External Walls

Fire safety in buildings starts with understanding how materials behave when exposed to heat. Testing external wall materials is crucial to keeping building occupants safe.

What tests can help identify high-risk building materials?

As outlined in PAS 9980:2022, the methodology for Fire Appraisal of Walls & Cladding of Flats, materials with a calorific value of ≤3 MJ/kg are considered to have a positive influence on fire performance, while those with >35 MJ/kg are flagged as higher risk.

The BS EN 13501-1 standard provides a harmonised procedure for classifying the reaction to fire of construction products, including those used within building elements. The standard identifies several test methodologies including the BS EN ISO 1716 “Calorific Value” test. This method plays an important role in cladding remediation works as well as compliance with regulatory requirements for high rise buildings.

What role does BS EN ISO 1716 have in the testing of external wall materials?

BS EN ISO 1716 testing plays a critical role by calculating the calorific value of the product. The results of the test will allow building stakeholders to determine the:

• Combustibility Risk

• Suitability of materials in wall systems

• Compliance with A1/A2 classifications in accordance with BS EN 13501-1 reaction to fire performance of construction products.

What are the seven classes that materials can achieve under BS EN 13501-1?

Reaction to fire testing examines the characteristics, such as combustibility, of building materials to determine their contribution to fire development and spread. Materials can then be classified into one of seven classes under BS EN 13501-1 according to their reaction to fire.

Non-combustible materials that do not contribute to the development of a fire will achieve an A1 classification with materials that have a limited combustibility that do not contribute to a fire will achieve an A2 classification.

The classification system then continues from B, where combustible materials with a limited contribution to fire will be classified, through to F where materials do not meet the minimum requirements of an E classification.

You can discover the full list of definitions and the required test methods by visiting our Reaction to Fire page here.

Why Reaction to Fire testing is critical for cladding remediation works

The ongoing cladding remediation programmes being carried out across the UK are crucial to the safety of occupants. Landlords of buildings 11m or more in height are required to complete any remediation works by the end of 2029 across England and Wales or face legal consequences.

Fire testing laboratories, like our UKAS Accredited Reaction to Fire Laboratory play a key role in allowing building stakeholders to identify risks. Reaction to Fire testing can produce the evidence to support whether materials can remain in place and meet the A1 and A2 classifications under BS EN 13501-1 or whether the materials need to be replaced.

If you’re specifying, designing, refurbishing, or assessing external walls, BS EN ISO 1716 testing is essential.

Talk to our reaction to fire team about testing your external wall materials by clicking here. Our industry leading report turnaround times ensure that you can make decisions and ultimately contribute to a safer built environment.