Upward Fire Spread Rate Over Real-Scale EPS ETICS Façades

Abstract

The expanded polystyrene (EPS) façade has been widely used to save building energy, but it has also caused many severe facade fire accidents worldwide. Especially for aged buildings, the naturally weathered exterior surface layer can further increase the facade fire risk and the fire spread rate (FSR). In this work, a series of real-scale EPS External Thermal Insulation Composite System (ETICS) façades are tested via the JIS A 1310 standard. The EPS thickness varies from 100 mm to 300 mm, density changes from 15 kg/m 3 to 30 kg/m 3 , and heat release rate (HRR) of window spilled flame ranges from 600 kW to 1,100 kW. Tests showed that the surface cement layer was quickly damaged by a spilled flame that provided negligible fire resistance for the internal flammable EPS panel. The measured upward FSR increases with the rising of HRR and with the decreasing EPS thickness like the thermally thin material. An empirical correlation of instantaneous upward FRS is proposed, FSR= 0.22Φ + 3.45 [cm/min], where Φ is a modified fire propagation index derived from the experimental temperature distribution. In addition, a simple prediction method for FSR is proposed for the façade fire and verified by the experimental data. This work provides a useful method to quantify the upward façade fire propagation, which also helps evaluate the fire risk and hazard of EPS ETICS façade prior to the costly large-scale tests and installation.

Fire Performance of EPS ETICS Facade: Effect of Test Scale and Masonry Cover

“…shows the EPS ETICS sample consisting of polymer cement mortar (PCM), cement mortar (CM), and EPS foam from the surface to the internal, same as past studies [15,23]. The PCM had 6% styrene-butadiene rubber (SBR) which was combustible.…”

“…1). Today, the measurements of fire-spread and heat release rate (HRR) of high-cost large-scale EPS facades [12][13][14][15][16][17][18][19][20][21][22][23] are still limited, so our understanding of EPS facade fire risk and phenomena is still relatively limited.…”

“…Also, the EPS is widely used in the vertical direction as insulation with finishing masonry coating in the facade so that their fire behaviors will be different from horizontal samples and the pure EPS facades. The fire dynamics of the whole EPS ETICS has been studied in limited tests, including the fire spread rate [17][18][19][20][21]23], fire rescue analysis [30], fire barrier influence on the fire performance [31], post-fire evaluation methods [20] and so on. Although it is clear that the vertical EPS exhibits a complex reactionto-fire performance because of its tendency to melt and flow, little knowledge is available for the EPS melt-flow process and the scale effect on the EPS facade fire HRR.…”

An Experimental Study of Pool Fire Characteristics under the Effects of Cross Winds and Baffles

“…Cross winds can accelerate the spread of fire by transferring additional heat, especially radiation heat, downstream, which can ignite the surrounding materials [35]. Therefore, the angle at which the flames tilt is an essential factor in determining the risk of fire propagation [36,37].…”

Upward Fire Spread Hazard of Vertical Greenery Systems: A Comparative Study with External Thermal Insulation Composite System and Double-Skin Façade

“…Incidents that occurred in Television Central Culture (TVCC) in Beijing, Wanxin Complex in Shenyang and Grenfell Tower in London are some examples of fires that were aggravated by insulation material [17,18]. Full-scale studies focused on the UFS of ETICS are rare in the literature, mainly due to the high cost of conducting large-scale façade fire tests [19]. However, the fire hazard of individual components (organic thermal insulation materials, in particular) of these composites has been studied in the past [20][21][22][23].…”