In the same way that the wheels of a car would not be tested alone in order to assess the performance of the entire car, the fire performance of a cladding system cannot be predicted based on a fire safety check of any any one component in isolation.
In reality, the fire resistance performance of a façade system depends on the interaction of all the components (including fixings, fasteners and sealants) in that system in response to a fire, and also on other design and construction factors such as the position of fire barriers, the size of ventilation gaps and more.