- Grenfell Tower-style building cladding catastrophically failed a government test. The material should have resisted flames for 40 minutes. It lasted less than 9. At its hottest recorded point, the cladding burned at 813.9°C
The type of cladding used on Grenfell Tower, the west London apartment block which killed at least 80 people when it burned down in June, caught fire in just 130 seconds in a government fire safety test.
The material, heated under scientific conditions to test its flame resistance, lasted less than a quarter of the minimum test standard before officials terminated the experiment because of how high the flames had reached.
Experts built a dummy wall meant to mimic the exterior of Grenfell Tower, and simulated a fire by lighting a stack of wooden pallets underneath it.
Here’s what it looked like before:
It took 130 seconds for the first parts of cladding to start burning. From then, the flames reached the top of the 9-metre test structure in 6 minutes, 35 seconds.
At that point it failed the test and officials put out the fire, a total of 8 minutes and 45 seconds after the wooden pallets were ignited.
At its hottest recorded point, the cladding burned at 813.9°C.
In order to pass, the cladding would have had to resist the flames for at least 40 minutes. As it stands, the material failed in less than one-quarter of that time.
The test was carried out in a warehouse by the Building Research Establishment in Watford, Hertfordshire, on July 23. Full results were published online by the government.
- BRE/Business Insider
The test was the first of six being carried out on different cladding variants to see how many tower blocks are at risk of catastrophic fires, similar to the one which consumed Grenfell Tower.
There are 82 buildings in the UK which use this cladding mixture, and therefore failed the test, according to government figures. Some 47 of them are public housing like Grenfell Tower.
The new tests are separate from an earlier round, which found that more than 190 buildings failed another type of fire safety test, where smaller pieces of cladding from each individual building were tested, rather than the large-scale demonstration outlined above.
The government has not named specific buildings which failed either test, though some have been identified by local authorities, NHS trusts, and the media.
Business Insider has been following the results and has published the most comprehensive publicly-available list, which is updated as new information emerges.