CLADDING TURNED A TINY FIRE INTO HELL
CONTROVERSIAL materials used to insulate Grenfell Tower may have helped turn a small fire into a deadly raging inferno.
Experts were last night focusing their blame for the scale of the disaster on external cladding fitted to the block only last year.
It was made from metal panels and slabs of a polystyrene-like material, separated by a small cavity, fixed to the concrete surface of the outside of the tower.
Together with new windows, the cladding was meant to boost the building’s energy efficiency, protect against the weather and smarten up the look of the 1970s facade.
But it appears to provide a fatal conduit for the flames to leap from one flat to another, with witnesses saying the outside of the block ignited ‘like a firelighter’.
There are fears that hundreds of high-rise blocks across the UK are fitted with similar materials – even though MPs warned of the potential fire risk nearly 20 years ago.
A report in 1999 by the Environment, Transport and the Regions select committee said: ‘We do not believe that it should take a serious fire in which many are killed before all reasonable steps are taken towards minimising the risks.’
The MPs highlighted concerns that the small air cavity between the layers of cladding can act as a chimney, helping the fire spread rapidly upwards. Their report demanded that ‘all external cladding sys- tems should be required either to be entirely non-combustible, or to be proved through full-scale testing not to pose an unacceptable level of risk in terms of fire spread’.
But the method was popular as councils sought to meet insulation standards laid out under the Blair Government’s £22billion Decent Homes Programme, which ran from 2000 to 2010. It continued to be used even after the 2009 fire at the 14-storey Lakanal House in Camberwell, South East London, which killed six people.
Sam Webb, a fire safety expert who helped gather evidence after that tragedy, said last
‘A cavity with a fire spreading behind it’
night there was a conflict between safety and the materials used to make buildings more energy efficient.
‘They are not fire-resistant and in some cases they’re flammable,’ he said. Fires involving cladding have also occurred in Australia, Russia and the Arabian Peninsula – adding to the serious safety concerns.
They include two in Dubai, one on New Year’s Eve 2015 at the 63-storey The Address Downtown and a second last July at the 75storey Sulafa Tower.
Grenfell Tower was clad last year as part of an £ 8.6million refurbishment by East Sussex-based builders Rydon, which said yesterday that its work ‘met all required building controls’.
Yet the company admits on its website that the insulation material used, Celotex RS5000, ‘will burn if exposed to a fire of sufficient heat and intensity… [and] toxic gases will be released with combustion’.
Design specifications seen by the Mail suggests Grenfell Tower had 150mm (6in) of Celotex RS5000 insulation and overcladding made from ACM – aluminium composite material – with a 50mm (2in) ‘ventilated cavity’ in between.
ACM is also potentially highly flammable and rescuers yesterday faced the hazard of blazing metal panels raining down on them as they tried to enter the building.
Arnold Tarling, chartered surveyor and fire expert with property firm Hindwoods, said the air cavity could create a ‘wind tunnel [that] traps any burning material between the rain cladding and the building’.
Had there merely been one layer of insulation, this could have fallen off and fallen away from the building but the metal cladding meant it was all contained inside. Not all insulation used in the process is the more expensive non-flammable type,’ he said. ‘So basically you have got a cavity with a fire spreading behind it.’
Dr Kostas Tsavdaridis, associate professor of structural engineering at the University of Leeds said: ‘The fire seems to have not only spread the inside the building but also outside. There is a trend nowadays where architects and designers use decorative materials to make buildings more interesting and aesthetically pleasing.
‘Some materials used in facades act as significant fire loads: although theoretically they are fire resistant, in most cases they are high-temperature resistant instead of fire resistant. But even if they are, smoke and fire will spread through the joints and connections.’
Grenfell Tower was equipped with metal overcladding by Harley Facades Limited, another East Sussex-based firm.
The company, which installed but did not manufacture the panels, said they were a ‘commonly used product in the refurbishment industry’. Managing director Ray Bailey said: ‘This is an incredibly tragic inci-
dent. Our thoughts are with the residents and their families who have suffered such a personal loss.
‘We will fully support and cooperate with the investigations into this fire. At this time, we are not aware of any link between the fire and the exterior cladding to the tower.’
Celotex, which is based near Ipswich said: ‘Our thoughts are with those affected by the terrible fire at Grenfell Tower in London. Our records show a Celotex product (RS5000) was purchased for use in refurbishing the building.
‘If required, we will assist with enquiries from the relevant authorities at the appropriate time.’
Plans for the externals works at Grenfell Tower were approved by the Royal Borough of Kensington and Chelsea.
In May 2016, after the work was completed, council leader Nick Paget-Brown said: ‘It is remarkable to see first-hand how the cladding has lifted the external appearance of the tower and how the improvements inside people’s homes will make a big difference to their day-to-day lives.’