Part 10.2:Fire protection requirements

All over Europe the basic requirements concerning fire protection measures in façades follow the same general rules:

• Requirements concerning the reaction-to-fire-classification of materials and/or systems
• Requirements dealing with the effective restriction of fire spread over the façade
• Requirements depend on the height of the building – the higher the building the stricter the requirements

Requirements are given in the national building codes of every single European country. No harmonized European building code exists!

Reaction to fire
More than 20 years ago, the fire classification standard EN 13501-1 for assessing the reaction-to-fire of construction products has been developed. It has been designed to test construction products in an easy and comparable way that also allows to test the product including mounting and fixing methods used in end use conditions.

Seven reaction-to-fire classes are defined (from best to worst): A1, A2, B, C, D, E and F. The classes characterize a products contribution to a fire, meaning that non-combustible materials of class A1 or A2 show no contribution, whereas products of class E deliver a significant contribution to a fire. Additional classifications for smoke production s1 to s3 and for flaming droplets/particles d0 to d2 are defined.

A classification report of an accredited testing institute is needed to prove the reaction-to-fire class of a construction product. Requirements differ a little bit all over Europe but one may come to the following common ground:

• Buildings up to 3 floors: minimum Class D-d0
• Buildings with 3 to 6 floors: minimum Class B-d0
• High-rise buildings (definition also differs from 18 m to 25 m): minimum Class A2

Due to the compact size of all the European reaction to fire-tests, the behaviour of full construction systems as well as the fire spread in façade fires may not be assessed which means that only requirements of reaction-to-fire-classes are not enough to ensure fire protection on façades fully.

Fire spread
To be able to evaluate this behaviour, national medium and large-scale façade fire tests are available. In these fire tests, the complete façade system including sub construction, insulation, air gap, cladding is tested. The test rigs all over Europe differ in the size of the fire load (wooden cribs 25 kg up to 600 kg or natural gas burners), the test period, the test specimen and the criteria (see figure 3).

Table 16: Comparison of national standards for fire testing of façades

Table 17: Comparison of national standards for fire testing of façades

Studying the national requirements for façade systems concerning the protection goal of an effective restriction of fire spread it becomes clear that all over Europe these national tests have to be positively completed to apply the system tested onto buildings with more than 3 floors.