Fire performance of sandwich wall assemblies

Fire performance is often identified as a difficult obstacle to overcome in designing lightweight sandwich panels suitable for use in building applications. Fireproofing generally increases the weight and cost of sandwich panels, reducing the field of application of such solutions. This study presents the fire performance evaluation of different non-loadbearing sandwich wall assemblies, based on the fire resistance test methods recommended by EN 13501-2, EN 1363-1 and EN 1364-1. The main objectives of the present study are: (i) to evaluate the fire performance of different core materials; (ii) to evaluate the fire performance of different fireproofing materials; (iii) to classify the fire resistance of different wall assemblies; and (iv) to design a sandwich panel which withstands a 60 min fire exposure without compromising its integrity (E) and thermal insulation (I) capabilities. Expanded polystyrene foam (EPS), polyethylene terephthalate foam (PET), cork agglomerate (CA) and stone wool (SW) were tested as core materials. Fireproofing gypsum boards (FG) and magnesium oxide boards (MGO) were tested as fireproofing materials. The skins of all sandwich panels tested were glass fibre reinforced polymers (GFRP). Cork agglomerate cores exhibited the lowest thermal decomposition rate under fire exposure and cork agglomerate core sandwich wall assemblies proved to withstand fire exposure for the intended duration, presenting the required performance, even dismissing the use of fireproofing boards.