Following the Grenfell Tower fire, there has been a massive emphasis on the need to ensure that any facade materials used in new or refurbished buildings meet stringent fire safety standards. Those that don’t will be banned by building regulations from May 2020. This means that any cladding material, including insulation products will need to have an A1 fire rating or higher. Fibre cement and terracotta will be able to comply with these new regulations, but other products such as uPVC and untreated wood, will not.
In a speech in late-autumn 2018, Communities Secretary James Brokenshire confirmed that there would be changes to the Building Regulations, which will limit the type of cladding material that can be used on high rise buildings to those with a Euroclass A1 or A2 fire rating. This will apply to both new and existing buildings, with the intention of preventing future tragedies like the one in Grenfell Tower.
The A1 classification is considered to be one of the strictest fire performance standards in existence, with A2 being the next lower level of fire resistance. In order to achieve this rating, a material must pass an extensive series of fire tests. These tests include burning, impact, water penetration, smoke generation, and flammability.
A1 cladding systems must be tested by a BRE-approved testing A1 facades house in accordance with the British standard BS EN 13501-1. The test involves setting up a simulated building with a concrete frame, the cladding panel, an air cavity space, and an intumescent or noncombustible insulating board (CI or WRB) underneath. The cladding panel is subjected to a simulated fire that replicates the conditions of a real fire and the integrity of the whole assembly is tested in relation to how the cladding panels, CI or WRB hold up and behave in the face of a fire.
A cladding system that passes the BS EN 13501-1 test will have an A1 or A2 fire rating. The results of the tests will also be published, so that builders and architects can check that they are using a compliant system.
ALPOLIC A1 is a non-combustible aluminium composite material that has been awarded an A1 fire rating by Mitsubishi Chemical Corporation (MCC). It’s available as a Secret Fix Hook On and Through Fix Cassette rainscreen solution through rainscreen cladding manufacturer Sotech, with a wide range of finishes to suit architects’ designs.
The material is made by laminating two sheets of aluminium to both sides of a core material, which creates exceptional flatness and load-bearing capacity. It is then colour-coated with the high-performance fluoropolymer resin LUMIFLON® on its front side, which offers resistance to weathering, UV radiation, corrosion, and colour fading.