Up to this point, you could still talk about budget constraints, tight trade-offs, decisions taken under pressure. You could still tell yourself that nobody really knew. Not any more. The risk is no longer a hypothesis. It is identified, documented, described in internal emails. And it is doing the rounds.
In British commercial practice, Reynobond PE was the product offered almost by default for facade jobs. When a customer contacted Arconic for facade panels, that was the one that came up first. Not because it was better. Not because it was more suitable. Because it was cheaper. And in a tender, the cheapest wins. Deborah French, UK sales manager, explained it bluntly to investigators 3:
By her account, the discussions were never about anything but PE.
Asked whether she had ever sold the fire-retardant version, the FR, Deborah French hesitated. Then she said no. Not once, as far as she could remember. In Germany, it was the other way round: FR was the norm. In the UK, it barely existed.
The PE in Reynobond PE stands for polyethylene. Plastic, sandwiched between two sheets of aluminium. FR is the same construction, with a fire-retardant core. Two letters’ difference on a purchase order. Deborah French knew polyethylene burned. She did not point it out to customers. She thought it was obvious.
One technical decision remained. How to fix the panels. Two options. The so-called “face-fixed” version, riveted straight onto the wall. And the “cassette” version, folded, hung on rails, with no visible rivets, smoother. Rydon, the main contractor, preferred the riveted version. It was cheaper. But RBKC’s planning department let it be known that visible rivets were an aesthetic problem. There were fears they would rust. They wanted a cleaner facade. The cassette version was chosen.
What nobody mentioned is that internal tests run by Arconic in 2011 showed the cassette version behaving far more dangerously in a fire than the riveted one. Faster spread. Higher energy release. More smoke. So the system finally fitted on Grenfell was neither the safest nor the cheapest. It was simply the one that looked best.
Before Grenfell, Deborah French had also received messages from competitors describing the chimney effect of PE panels on facades. Fire racing from bottom to top, or the other way, in minutes. She had passed them on internally. The information had circulated. It had changed nothing.
At Arconic, other emails were circulating. Claude Wehrle, a technical manager, had been sending warnings to his superiors for years. In July 2009, he had forwarded photos of a fire in Romania involving PE panels, with one word. Dangerous.
A warning shared again in 2012, then in 2013 by Deborah French. No reaction.
Then in June 2015, while Reynobond PE was being fitted on Grenfell Tower, Wehrle wrote:
PE, he warned, was DANGEROUS on facades, and everything should be switched to FR as a matter of urgency.
Then he added, with a smiley:
That view, he noted, was technical and, it seemed, anti-commercial.
A few months later, he came back to it:
Arconic really had to stop offering PE for architecture, he argued: the company was in the know, and it was up to it to be proactive.
These emails were not whistleblowing. They were internal notes, filed away, read by people who did not have the power to change sales policy, or did not want to.
And yet there were public documents. Arconic’s sales brochure for the European market contained an explicit diagram:
Grenfell Tower was 67 metres tall.
The brochure was available to anyone who bothered to read it. It was never treated as a constraint. It existed as one recommendation among many, buried in the technical documentation.
But there was also a precedent. In 2012, a fire broke out in a flat in Taplow tower, on the Chalcots Estate in Camden. The building had the same type of ACM cladding. The cladding subcontractor was Harley Facades. The main contractor, already, was Rydon. After the fire, Harley Facades wrote a report. The fire barriers around the windows had worked. The fire had not spread from one flat to another.
Stephen Blake, Rydon’s director on the Grenfell project, was on the report’s distribution list. He had visited the damaged flat. He had been photographed pointing at the intact fire barriers. He could not have been unaware. But nobody then checked whether equivalent barriers existed at Grenfell. Spoiler: they did not.
The purchase order was signed. The material was delivered. Harley Facades’ teams started installing it. In Arconic’s offices, Claude Wehrle’s emails stayed in the archives. At Studio E, nobody reopened the European brochure. At KCTMO, nobody knew there were several versions of the same product.
The PE was compliant.
It was budgeted.
It was fitted.
On to the next file.