ASSESSING AND IMPROVING THE FIRE PERFORMANCE OF BUILDING ENVELOPE SYSTEMS – WITH A FOCUS ON ETICS SYSTEMS WITH AND WITHOUT FLAME RETARTED EPS

Ensuring fire safety of high-occupancy buildings is one of the key aspects that must be addressed alongside energy-efficiency to achieve the sustainability goals throughout Europe. Unfortunately, the Grenfell Tower disaster, which, in addition to the 72 fatalities, has had financial impacts greater than the average yearly fire costs in the UK, revealed that there is a massive need for improved knowledge on how to provide fire safe building envelopes in building projects (new and renovation). The most common type of facades used in new construction and renovation projects are ETICS (External Thermal Insulation Composite System), Cavity Walls and Ventilated Facades. ETICS is of particular interest, as it covers the largest percentage (2/3) of the market. This is due to the fact that this solution is used for a large variety of building types, including high-rise residential buildings, hotels, offices, warehouses and storage facilities. The improved fire safety of building envelopes should largely rely on a more fundamental understanding of the potential failure modes in the systems in use. To identify the failure modes from a fundamental perspective, more parameters have to be thoroughly measured in tests, and tests at different scales should be carried out to highlight different critical scenarios. The reason for this is that it is expected that small-scale tests can identify problems that will be critical at a larger scale. However, this requires a higher sensor density than what is currently offered by pass/fail standard tests, because it is expected that the identification might be based on trace values in one or more of the measured parameters. In addition, as smoke is the main fatality cause in fires, the tests should, contrary to current practice, include measurements not only of smoke production, but also of smoke characteristics in order to establish acute toxicity. Finally, the research will also focus on the effectiveness of flame retardants on the overall fire performance. Given the increased health and environmental concerns associated with some flame retardants, it is important to establish the benefits of using flame retardants to improve the overall fire behaviour of façade systems. The current research project will therefore focus on developing an iterative test process to achieve a comprehensive understanding of the fire behaviour of façade systems. Starting with large-scale tests of ETICS facade systems (that will be based on the latest developments in research), mid-scale tests using two different rigs will follow, and then full scale tests will be carried out again, and so on. The new state-of-the-art fire laboratory in Logatec has the unique capabilities required for this project, namely high-fidelity, fundamental measurements, even for the large-scale façade tests that will follow and exceed (through added parameters, more sensors and higher precision) the new European standard that is in development. The high-fidelity measurement using a high density of sensors for a uniquely large number of parameters will enable a detailed analysis that can be used to establish the desired measurement sensitivity for failure identification, and thus more appropriate classification of the façade system. In addition, such high-fidelity and high sensory density measurements can also pave the way for improved numerical modelling. Overall, the project aims at leading the way towards a safer built environment, with lower energy consumption and increased sustainability.