Grenfell: BRE report on failed Kingspan fire test used to support 29 desktop studies

A failed fire test involving Kingspan’s K15 insulation – a quantity of which was used on the Grenfell Tower refurbishment – was used to support 29 desktop studies justifying the use of the product on high-rise buildings.

This was after the BRE provided a written report on the test that failed to make its result clear.

Kingspan’s use of the report emerged during yesterday’s (25 February) Grenfell Tower Inquiry hearing, which saw former BRE burn hall manager Philip Clark give evidence for a third day.

The March 2014 test at BRE’s burn hall saw K15 tested as part of a high-pressure laminate (HPL) cladding system to BS 8414-2.

When it was submitted to fire testing, video footage recorded Clark observing flaming above the rig after 43 minutes. Under official criteria, the test should have been terminated but Clark allowed it to continue. However, his notes did not record that flames were “definitely over the top” of the rig.

Following the test, Kingspan made a complaint to dispute the outcome of the March 2014 fire performance test.

But the BRE held its position and the system was never classified to BR 135 (Fire performance of external thermal insulation for walls of multistorey buildings).

Nonetheless, the BRE agreed to a request from Kingspan to provide a written report about the test, even though the tested system could not be classified to BR 135. Clark agreed that the test report “doesn’t necessarily, unless you thoroughly read it, make it clear that the system has failed”.

Millett asked Clark: “Are you aware that the test report which you, in the end, did issue to Kingspan in relation to the March test… was used as the basis of a number of desktop assessments to BR 135 on systems incorporating K15?”

He continued: “Did you know that there were 29 desktops in total, so far as we have been able to count them, based on this test report, which had in fact failed?”

Clark replied: “No, I wasn’t aware at all, no.”

Millett added that of the 29 desktop studies identified, three were BRE desktop studies. He said: “Take it from me that not a single one of those 29 assessments, including those done by the BRE, refers to the fact that the March 2014 test failed to meet BR 135 criteria. Did you know that?”

Clark replied: “No, because this is the first time I have ever heard that, and I find that very strange and, to be honest, slightly shocking.”

Earlier in the exchange, Millett asked Clark why, given the risk Clark had identified that “Kingspan might well try to pass off a fail as a pass if they’ve been given a test report”, he had not added a caveat to the test report so that anyone seeing it would know the test had not met the criteria for BR 135.

Clark said: “I understand entirely. Within the industry, I don’t think that’s common practice. Obviously if it’s a classification report, it will clearly state what the classification is, but in other things – – I suppose you could have something that says ‘criteria not met’, but the issue with that is that BS 8414 doesn’t have any criteria, it’s just a test.”

Desktop studies, which refer to a study carried out purely through research rather than physical investigation, were criticised in the wake of the 2017 Grenfell Tower fire, when it emerged that they were often used to assess the fire safety of cladding systems, rather than full-scale physical testing.

In her independent review into Building Regulations and Fire Safety published in 2018, Dame Judith Hackitt raised concerns about the lack of supporting test data and the competence of some assessment authors. Hackitt’s report recommended reducing the use of desktop studies although she stopped short of recommending a total ban.

In April 2018, the Ministry of Housing, Communities and Local Government (MHCLG) published a consultation that proposed limiting the use of desktop studies for assessing the fire performance of external cladding systems.

The Inquiry continues.