BS 8414 is a large-scale reaction to fire test developed specifically to assess the performance of complete cladding systems in application. The test is designed to replicate a fire which has begun in a room, reached flashover and broken out through a window exposing the external façade to fire.
It has two parts, both using the same testing methodology:
- Part 1: 2002 (Test methods for non-loadbearing external cladding systems applied to the face of a building)
- Part 2: 2005 (Test method for non-loadbearing external cladding systems fixed to and supported by a structural steel frame).
Performance criteria for assessing cladding systems tested using BS 8414 is contained within BR 135 (Fire performance of external thermal insulation for walls of multi-storey buildings). At present complete cladding assemblies which meet these criteria can be deemed compliant with the relevant Building Regulations and Standards in England, Scotland and Wales for the following high-rise applications:
Scotland & Wales
— all building with a habitable storey 18 metres or more above ground level.
— commercial buildings with a habitable storey 18 metres or more above ground level.
What happens in the BS 8414 test?
The test uses a two-winged rig at least 8 metres in height with a main face that is at least 2.4 m wide along with a min 1.2 m wide side wing. The cladding system under assessment is installed on both walls of the rig as it will be in the final application (including all joints, seals and fire breaks). Temperature sensors (thermocouples) are installed within the system at set heights (seen in diagram) and a 2x2 m wooden crib is placed at the base of the main face.