In this post I am going to explain you the basic aspects about the reaction to fire tests on the external thermal insulation composite systems, ETICS.
What is an ETICS?
First, an ETICS is an external thermal insulation system that it adheres to the façade either with an adhesive orthrough mechanical fixings. After fixing system, the thermal insulation material is mounted. The reinforcement meshes and the surface finishing layer/s are installed on the insulation.
With regard to the reaction to fire tests, they will be adapted to the class desired. Normally, the usual classifications will be A2 and B, although depending on the type and quantity of the components of the systems, it would be possible to reach an A1 class. It is important to note that the classifications of the ETICS systems apply to the whole system, not to its individual components, and this will be reflected in the classification report.
What tests are involved?
As you already know from other posts on my blog, each Euroclass of reaction to fire requires specific tests.Therefore, depending on the euroclass that you want to achieve, you will need to conduct tests that I show you now.
Figure 1. Tests required for each euroclass according to the EN 13501-1 standard.
At this point, it is crucial to test the products or systems according to the end use application, that is, with thenumber of layers as well as the density, thickness, etc. required in the reallife. Otherwise, if an ETICS system is installed with layers that have not been taken into account in the tests, the fire tests carried out on another system will include the system tested.
What do I test if I have a range of thicknesses of insulation or meshes?
A reaction to fire test applies only to a product, system or material. But when you have a range of products either by varying the thicknesses or densities of the individual components of the product, you should make to the EXAP process (Extended Applications) as long as they are included in a harmonized document, either through a product standard for the CE marking or ETAG guide.
In the case of ETICS, there is the guide ETAG 004 «External Thermal Insulation Composite Systems with Rendering». In Annex D it is explained that the worst case will be tested. The parameters that this document considers as influential in the behaviour to fire are:
- Type of insulation (Composition, thickness and density).
- Type of finishing (Composition, thickness and mass per unit area)
- Type of mesh (Composition, thickness and mass per unit area).
- Type of fixations.
- Type and nature of the barriers.
- Organic content of the adhesives and any other additive.
- Type and amount of flame retardant.
For each of the tests involved to classify the ETICS system, the document includes the extensions of the results allowed. All this information will be shown in detail in the technical reports issued by the laboratories responsible for the tests.
And what happen in the reality?
Sometimes, I have received comments from the inspection services that at the time of inspecting buildings with this type of system, fire reports were not available. Without this information it is impossible to know the classification of reaction to the fire of the system and consequently the current legislation would not be fulfilled.
On the other hand, if you have the reports but there are elements of the system that are not the same as those shown in the reports, that is, there are variations that are not allowed, the ETICS system will not have a classification, due to it only applies to the system described in the reports with the variations shown.
How will it be in the future?
At present, the ETICS systems are evaluated through the Euroclasses according to the EN 13501-1 standard but a new harmonized methodology is being developed in Europe to evaluate the behaviour of the façade systems. This new method will apply to ETICS, ventilated façades, curtain walls, etc. At the moment it is in the development phase and its application will not be immediate.
Fire Safety Consultant