Experimental study of time‐averaged upward fire propagation speed of expanded polystyrene external thermal insulation composite systems masonery façade

Abstract

SummaryThermoplastic expanded polystyrene (EPS) external thermal insulation composite systems (ETICS) have caused serious results due to the ravages of frequent fire disasters in the world. Fire propagation of EPS ETICS was observed to be fast over exterior building wall, however, very few reports of time‐averaged fire propagation speed (FPS) is available currently. To have a quantitative understanding of FPS, a series of EPS ETICS façades were tested according to the intermediate‐scale Japanese JISA 1310 standard method. EPS thickness of ETICS varies from 100 mm to 300 mm and heat release rate (HRR) of window spilled flame differs from 600 kW to 1100 kW. It indicates that the time‐averaged FPS vs vertical distance is observed to be positive linear. The acceleration of FPS is found to be linear with a dimensionless item, which involves fire propagation index (FPI), HRR of window spilled flame and thickness of EPS. Finally, a calculation method for an upward fire spreading profile is proposed, which initially provides a theoretical basis for evaluation of the reaction‐to‐fire performance of EPS ETICS façade.