With a mountain of cladding remediation work to get through, CN asks how contractors can ensure their work avoids contributing to fire risks
A fire at an East London residential block last August was a grim echo of the Grenfell Tower blaze, which killed 72 people seven years earlier. Thankfully, the fire at the Spectrum Building in Dagenham did not result in any deaths – although the building was so badly damaged it had to be demolished. One resident who saw the flames from his window told the BBC: “It was as though I was seeing a horror movie.”
Like Grenfell Tower, the Spectrum Building was clad with a dangerous material. In this case, the cladding was high-pressure laminate. Unlike at Grenfell, where combustible cladding had been installed across the whole building, high-pressure laminate only featured on the block’s fifth and sixth floors. The building was in the process of being remediated when fire broke out. By that point, the dangerous material had been removed. So why did the fire spread so quickly and fiercely?
“The precautions that are designed in to make the building safe during its normal operation can easily be affected by the [remediation] work”
Neil Gibbins, CROSS
Scaffolding surrounded the block as a result of construction works. Despite speculation, it is not yet clear whether the remediation project itself played a role in the fire. A joint investigation by the London Fire Brigade (LFB) and Building Safety Regulator is ongoing. But an LFB spokesperson has confirmed to Construction News that the investigation is looking at whether the remediation project was a factor.
Whatever the outcome, contractors carrying out cladding remediation work need to be acutely aware of fire risks, as the amount of work in this area remains vast. So what are these risks? And what should contractors be doing to ensure they can avoid a potentially lethal fire?
Remediation risks
The first thing to consider is that buildings needing remediation are already high risk, says Neil Gibbins, lead fire safety expert at CROSS, a confidential building safety reporting scheme. “During the process of removing the cladding or facade, you expose the internal structure of whatever the facade was built of,” he says. “That in itself increases risk.”
Another key danger is that remediation projects normally involve scaffolding, which has potentially combustible timber boards. Arnold Tarling, a fire safety expert and chartered surveyor, says: “These boards can act as pathways for fire to spread rapidly up a building’s exterior.” There is also the risk of combustible materials being stacked on the scaffolding until they can be transferred to a safe place, says Gibbins.
“Exposed materials, malfunctioning safety systems and incomplete structural work can pose serious hazards”
Paul Trew, Institution of Fire Engineers
Then there is the work to remove the cladding itself, which can involve hot cutting and grinding. “There might be situations where burning torches are needed to remove fixtures that have been there for 20 or 30 years,” says Gibbins.
Once the dangerous cladding is removed, it needs to be stored safely. Tarling points to the risk of highly combustible materials accumulating at the bottom of the building. There are lots of questions to consider, he says: “Is the combustible material being put into skips? Is it being put into enclosed containers? If it does catch fire, will it be retained in the container? How close is it to the property?” He adds that arson always remains a risk during building projects.
Another factor to take into account is the existing building regulations and fire safety arrangements for a property and how remediation work could affect those.
“The precautions that are designed in to make the building safe during its normal operation can easily and regularly be affected by the [remediation] work,” says Gibbins.
A CROSS report from last October revealed that in one instance, a sprinkler system was deactivated during construction works. “It is becoming increasingly apparent that contractors often fail to recognise the risks associated with disabling critical systems in an occupied building,” the report said.
CROSS has also identified workers on site “unknowingly” blocking automatic operating vents (AOVs), which can remove smoke from a corridor if a fire breaks out. “Most people living and working in buildings have no idea that the building has such a facility fitted,” says Gibbins. “There is no sign on the window.” But the consequences of AOV malfunctions can be deadly.
Two CROSS reports published last year focused on this particular problem. In one case, a residential block undergoing remediation was “compromised” by a subcontractor covering the AOVs with masking material. The report laid out the consequences in stark terms. “Failure of either of these AOV types to operate could result in the stairwell and corridors becoming smoke-logged, causing occupants to become trapped in their flats with no way of safely escaping a fire,” it said. “This smoke and heat may also impede firefighting and rescue by firefighters.”
Remediation work also often involves a plastic skin being wrapped around the scaffolding to protect workers from the weather. “The material should not be combustible,” says Gibbins. Even if it isn’t, he adds: “It will change the dynamics of the air around the outside of the building – potentially causing a chimney-like effect, where you’ve got an opening at the bottom, an opening at the top, and then vertical airspace that would allow fire and smoke to travel very quickly up along the face of the building.”
Patchy understanding
Ben Ralph, director at multidisciplinary consultancy Hollis and a chartered fire engineer and mechanical engineer, feels understanding of unsafe working practices in the sector is “patchy”.
“There’s an awareness around the use of combustible materials in temporary structures,” he says. “But the awareness of considering how those temporary structures and the temporary arrangement impacts the fire safety strategy of the building is lower.”
CROSS reports have also identified cases involving a lack of communication between contractors and the person responsible for the building. Gibbins says this can result in a “very difficult discussion” over the fire safety approach. “If it impacts on an existing sprinkler system or the fire alarm system, it may well be that the building has to move to have a waking watch.
“This is a building owner’s nightmare, having to pay for people to be walking around. It’s a huge cost and likely to be unexpected.”
Poor practices can negatively affect residents, the very people who are ultimately supposed to benefit from the remediation work. The costs of waking watches are often passed on to residents themselves, which adds financial stress to the anxiety of already living in a high-risk building.
Paul Trew, technical director at the Institution
of Fire Engineers, says waking watches are often paid for through higher service charges. “The persistent fear of fire can have psychological effects and generate anxiety and stress among residents,” he adds.
Further stress is caused when a contractor carrying out a remediation project goes bust. “This situation can cause delays in work, leaving buildings unfinished and potentially unsafe,” says Trew. “Exposed materials, malfunctioning safety systems and incomplete structural work can pose serious hazards.”
Dynamic risk assessments – which require safety information to be updated in real time – are seen as one way to minimise risks. But some firms are reluctant to pursue this approach. “Cost is a significant barrier, as implementing these assessments requires investment in specialised tools and training,” says Trew. “Some organisations may also struggle with the time and resources needed to conduct ongoing assessments and follow through with necessary actions.”
There is also concern that the fragmented nature of supply chains discourages individual firms from taking responsibility. Organisations’ testimony to the Grenfell Tower Inquiry displayed such an attitude, which counsel Richard Millett described as a “merry-go-round of buck-passing”.
Ralph says he is greatly concerned by the “fragmentation of the supply chain”, particularly when it comes to remediation jobs. “The size of individual organisations are getting smaller and the individual supply chain is getting more and more fragmented,” he says.
This can result in cutting corners. “The things that cost time and money – such as sending folk to get trained up and [improving] skills and knowledge and behaviour – become really, really difficult with a super-fragmented supply chain.”
‘A long way to go’
It is worth remembering the amount of remediation work that still needs doing. Government figures published in March revealed that 2,586 buildings taller than 11 metres with unsafe cladding had not started remediation by the end of February. This represents just over half of the overall total of 5,014. And that’s only the buildings we know about. A National Audit Office (NAO) report last November concluded that up to 60 per cent of buildings with dangerous cladding in England – an estimated 7,200 further buildings – were still yet to even be identified.
Fire chiefs are also sounding the alarm. In February, the National Fire Chiefs Council called for an “industry-wide action plan” to tackle the backlog. As Gareth Davies, head of the NAO, said: “There is a long way to go before all affected buildings are made safe.”
Last December, the government announced a remediation acceleration plan aiming to fix all buildings taller than 18 metres with dangerous cladding by the end of 2029.
With the remediation pipeline greater than ever, Gibbins has a firm warning for the firms that will take on that work. “Business-as-normal is not enough in a building going through remediation,” he says. “And that needs transmitting through the chain of people who are working on a building when it is at its most vulnerable.”
What have contractors learnt from remediation jobs?
For Tom Rutter, managing director of Hampshire-based cladding remediation specialist T&T Facades, the biggest risk is around how you move and store combustible materials. He says that on his firm’s jobs, when the cladding comes off it is taken to a skip a “significant distance” from the building. “Then if the worst did happen and that skip went up [in flames], it can’t affect the building,” he says.
Among the other risks he highlights is the possibility of a resident disposing of a cigarette out of a window and igniting flammable materials. “That is an identified risk that we manage on all projects,” he says.
As such, building a relationship with residents is key, says Rutter. When scaffolding is up, often residents will be unable to use their balconies and have their view blocked by the sheeting around the scaffolding. But he says that “giving people fair warning and explaining to them why you need to do it and how long you’re going to do it for, in most instances, is enough”.
The company is tackling new record-keeping obligations with a photographic survey. “We have a golden thread of information which identifies where the materials have come from,” says Rutter. “There’ll be a photographic survey of what the building looked like beforehand, what it looked like when we’ve removed the materials, what it looked like during the process of removing those materials, what we had to do to rebuild it, and then the finished product at the end of the day.”
And for Rutter, nothing beats accumulated knowledge when it comes to dealing with remediation jobs. “Experience and having an understanding of what you’re up against is key,” he concludes.