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Summary: The serious fire incident at Grenfell Tower in London, involving a combustible façade system that was installed as part of a major refurbishment of the building, has raised concerns regarding the fire risk that these systems pose. The fire spread over the façade of the Tower was previously numerically modelled and this model was validated by comparison with observational data. This model was used to determine the fire behavior of the façade and the fire's propagation into apartments through windows. In the present paper, impact models are used to evaluate tenability conditions inside the Tower, especially for the apartments in the first corner of the Tower that caught fire. The source of toxic effluents includes the components used in the refurbishment of the façade and the apartment furniture. Different hypotheses of gas yields are tested to assess variability and unknowns in the burning conditions. An extensive literature review was conducted to investigate the toxic yields to be considered in the simulations. Tenability conditions are assessed for each apartment during the fire spread over the façade. This leads to the quantification of the thermal and toxic environment inside the apartments. Two different models are tested for thermal and toxic threats, and the influence of the insulation material used in the façade is investigated. The results showed that the same conclusion can be made regardless of the input data for toxicity and the model used, within the limits of the studied dataset and conditions. Fires from the apartments quickly drive tenability conditions, independently of the dataset and model used, and even if mineral wool is used instead of poly‐isocyanurate as façade insulant. [ABSTRACT FROM AUTHOR]

Summary: The tragic events at Grenfell Tower in 2017, involving a combustible façade system, have raised concerns regarding the fire risk that these systems pose. In this series of articles, so far published, fire development inside the initial apartment has been investigated using an appropriate computational fluid dynamics (CFD) model. Several scenarios including different fire sources and ventilation conditions were addressed. Fire propagation through the window to the external façade and to higher apartments was modelled. This model was validated by comparing the numerical results with the visual observations reported in the Grenfell Inquiry. A CFD model of the complete east face of the Grenfell Tower was then created. This paper details CFD modelling of the complete Grenfell Tower façade during the late horizontal phase of fire spread. As the physics of lateral flame spread is different from that for upward flame spread, it is important to assess the validity of the model, thus far developed, for this configuration. Fire propagation over the whole façade is modelled and compared with observations from the real disaster. This provides a better understanding of its fire behaviour and of the contribution of architectural details and their impact on fire spread. [ABSTRACT FROM AUTHOR]

Summary: The dramatic event of the Grenfell Tower in 2017 reminds the importance of addressing fire issues as a whole and clearly highlighted one of the major roles played by the façade as fire propagation vector. To understand and analyse this disaster, numerical simulation allows particular phenomena to be evaluated more easily. The numerical model addressed for the fire behaviour of the façade system was developed using a multiscale approach and validated at different scales. In this paper, the fire behaviour of the façade and of its window frames is addressed. A computational fluid dynamics (CFD) model is used to investigate the fire spread from the initial apartment to the overall façade with different scenarios for the fire source and ventilation. Fire propagation through windows to the façade and to upper apartments is addressed. General curves representing the re‐entry of flames into upper apartment are extracted from simulations. The numerical results are validated by comparison with observations from videos and pictures of the real fire. Numerical results show that whatever the initial fire location and ventilation conditions, even if the fire source is of hundreds kilowatts, it is enough to ignite the adjacent element early and to the appearance of external flames shortly after. [ABSTRACT FROM AUTHOR]

Summary: The dramatic event of the Grenfell Tower (June 2017), involving a combustible façade system, has raised concerns regarding the fire risk that these systems address. Indeed, as façades are complex systems, it is not straightforward to assess which part of the system is involved in the global fire behaviour. Understanding such façade fires is thus very complex as it depends on a combination of various products and system characteristics, including window frames or air gap or cavity barriers. Fire development inside the initial apartment was investigated using an appropriate CFD model with different scenarios for the fire source and ventilation conditions in a previous study. Fire propagation through the window to the external façade and to higher apartments was modelled and validated against visual observations. This paper describes CFD modelling of the complete Grenfell tower facade, and investigates vertical fire spread behaviour over the full height façade from the initial apartment. Contributions from the combustion of all the apartments' furniture, depending on window failure, and architectural details of the refurbished façade are considered in the numerical model. The modelling results are validated by comparison with photographic and video observations of the real fire. [ABSTRACT FROM AUTHOR]

Summary: The recent fire events in buildings involving combustible cladding systems have raised concerns regarding the risk that these systems can pose. Understanding such facade fires is complex as they involve a combination of various products and system. Facade fire propagation tests at ISO 13785‐1 intermediate scale were performed on different combinations of aluminium composite material (ACM) claddings and insulants. Simulations were addressed to reproduce these tests and were validated in terms of thermal conditions in the system. This allowed additional investigation and understanding of fire propagation on the facade and more accurate determination of the fire behaviour of the overall system. In this paper, the scaling influence on the fire behaviour of ACM clad systems is investigated with simulations performed to reproduce fire tests at the BS8414‐1 larger scale on three different combinations of ACM and insulants. The contributions of the cladding and insulant were numerically investigated. The fire behaviour of each component and of the overall system is validated by comparison with experiments. Simulations and tests show that the ACM cladding is the most important element driving the global fire behaviour of the systems. In particular, ACM‐PE‐based cladding systems, whatever the insulant, show extensive fire propagation while its degradation affects the integrity of the cavity. [ABSTRACT FROM AUTHOR]

Summary: Increasing the energy performance of buildings is a crucial sustainable development objective. However, building features, products, mounting, and fixing of façade components have a large impact on fire safety. Authors in previous study performed façade fire propagation tests according to ISO13785‐1 on different combinations of ACM claddings and insulants. In this paper, simulations are performed to reproduce three of these tests. The model is validated with the aforementioned experimental results, including details in terms of thermal conditions in the system. This allows better understanding of the fire propagation on the overall system. Additional information, such as the relative contribution of the cladding and the insulant, are investigated numerically. The fire behaviour of each component of the overall system is thus validated. Simulations and tests performed show that the ACM cladding is the most important element driving the global fire behaviour of façade types considered. In particular, ACM‐PE–based cladding systems show large fire propagation whatever the insulant. This series of simulations is a part of a larger study including several steps of increasing complexity. Once the model for the fire behaviour of façade system is validated at intermediate scale, larger façade systems will be investigated numerically to evaluate the influence of scaling. [ABSTRACT FROM AUTHOR]