Parallel panel experiments on cladding and insulation systems: overall behaviour and relative contributions to heat release

To investigate the system behaviour of combinations of cladding and insulation, ninety-four experiments were performed on parallel panels. The experiments involved 1.2 m high, 0.5 m wide panels separated by a cavity between 25 and 200 mm wide. The fire source was three line burners at the base of the apparatus with a combined heat release rate of 8.5 kW. Insulations tested were Mineral Wool, PIR and Phenolic. Analysis of the resulting heat release data allowed the different systems to be ranked by various metrics. The tested systems could be placed into three groups: 1) Aluminium Composite Material with a polyethylene core paired with an insulation – these systems produced the highest heat release rate (between 545 and 654 kW); 2) cellulose based cladding panels paired with any insulation – these systems produced between 7 and 224 kW; and 3) non-combustible claddings with any insulation – these resulted in fires of less than 7 kW. The presence of combustible cladding was the greatest determinant of maximum fire size. The presence of combustible insulation also increased the maximum fire size, but to a lesser degree. When combustible insulation was paired with a combustible cladding, it contributed 10-28% of the overall heat release from the system.