The rise of combustibles

These tests are shrouded in secrecy.

The BRE does not release the results, deeming them commercially confidential, and leaves it up to individual manufacturers to tell the market what happened to their own products.

The BRE says this confidentiality is a requirement as a UKAS accredited test laboratory. "If we do not, we risk losing our accreditation," a spokesperson for the BRE said. "And those manufacturers that have tests done are required to represent them accurately in information to underpin the use of their products."

A test on the Celotex product used on Grenfell – in combination with non-flammable cement fibre insulation – was withdrawn in January after the manufacturer admitted “inconsistencies” between the test and the way it was marketed. What these inconsistencies were has not yet been revealed.

The BRE does not design the individual tests, leaving it up to manufacturers to decide what sort of fire breaks to use, what gaps to leave between panels and where to place the monitoring devices that determine a pass or fail in relation to the barriers.

Data from the tests is also used to clear untested combinations of materials, based on an assumption that they will also pass – a process known as ‘desktop studies’.

Approved Document B

To clearly understand how this picture has emerged as the status quo, we need to go back to the early-1990s.

In 1992, the government’s official guide to building regulations, Approved Document B, effectively banned combustible insulation outright and had no provision for large-scale testing.

But it was a fatal fire at Garnock Court in Irvine, Scotland, in 1999, which killed a 55-year-old disabled man, that first introduced the testing route.

A parliamentary inquiry into the fire was conducted by the cross-party Environment, Transport and Regional Affairs Committee.

Three key witnesses to this inquiry were from the BRE: Peter Field, Sarah Colwell and Tony Morris.

The BRE had been privatised in 1997 as one of the last acts of John Major’s government before Tony Blair took power. Now that it wasn’t a government agency, it was forced to rely on income from manufacturers who wanted to test their products.

It does this for many products, of which large scale fire testing is now only a small part, representing just 1% of its income.

When the inquiry began the BRE was in the middle of developing the large-scale testing method.

The minutes to the inquiry record that Mr Field said “all forms of cladding” should be tested using this method or other similar methods.

A spokesperson for the BRE adds that it is "categorically not the case" that the motivation in recommending full scale fire testing was because of a vested interest in growing a market for this form of test. "The point of the large-scale test was (and still is) that cladding systems with their full design should be tested as they are intended to be used on a building. This is to provide a full understanding of how an actual system will perform," the spokesperson added.

The review of Approved Document B which resulted from the inquiry introduced large-scale testing – but not quite as widely as Mr Field suggested.

Fire Note 9 – a document written by the BRE outlining the rules for testing – was officially endorsed by the 2000 version of the approved document. However, originally this test was only to be used for external surfaces that didn’t meet the requirements. There was still no way in for combustible insulation.

The 2000 version of the guidance stayed in place for six years, but discussions about changing it began as early as 2003, when John Prescott, then deputy prime minister, published a white paper on fire safety.

The government’s new plans for fire safety included changing Approved Document B to focus more on preventing fires in residential buildings. Ironically, the eventual guidance that would result would open the door to the use of desktop studies and combustible insulation.

The review began in 2005. According to the annual report of the Building Regulations Advisory Committee for 2004, the BRE organised all the initial meetings to discuss possible changes to Approved Document B.

The BRE’s website states that Mr Prescott appointed it to support the review.

In fact, when the new edition of Approved Document B went out for consultation, respondents were instructed to send their suggestions directly to the BRE’s office in Watford, not the government headquarters in Westminster.

When the document was sent out for consultation, it was proposed that the tests no longer be used for external surfaces walls and instead be used to clear combustible insulation for use.

Crucially, the wording was also changed to require that materials be approved from “full-scale test data” rather than a full-scale test.

It is this wording that gave the industry the confidence to believe they did not need to actually test the combinations of products they were using, and could instead clear them from data in other tests.

The final version of Approved Document B that resulted from this consultation actually gave even more backing to the testing process, expanding its use to both external walls and insulation.

At no point during the consultation did the government draw attention to this change, and it never appeared in any summary of significant changes, despite the fact that it fundamentally altered the meaning of building regulations towards combustible insulation.

The BRE has said these changes “would have been compiled, scrutinised and approved by the Building Regulations Advisory Committee” which it was not represented on.

“It was a complete race to the bottom.”

More generally, it adds that “testing systems at large scale is a rigorous scientific way of testing performance and ultimately keeping people safe”, and says it is not aware of any block tested to BS 8414 standards that has suffered external fire spread.

It said in response to questions from Inside Housing: “The use of a BS8414 test as an alternative to using limited combustibility cladding was introduced after a number of fires occurred in the late 1980s and 1990s in tower blocks that had been overclad to improve their thermal performance.

“Prior to these fires, the notion of regulating the fire performance of externally -applied retrofit insulation had not been considered as it had not become ‘an issue’.”

Desktop studies

Building control officials at councils and commercial private approved inspectors were then asked to interpret the newly loosened Approved Document B, which went from simply banning combustible products to requiring them to check test data to make a judgement about whether or not it would pass.

Some commentators have raised concerns that in the face of commercial competition for building control services, council inspectors were reluctant to refuse permissions.

One cladding manufacturer tells Inside Housing: “It was a complete race to the bottom. [Building inspectors] would approve everything just to get the market share of building control.

“Once the door was opened by the BRE and the then Department for Communities and Local Government in 2006 by that subtle change in wording in Approved Document B, the whole thing just unravelled, and they signed off anything.”

The Building Control Alliance, which represents building control officials, moved to formalise this process in June 2014.

It did this through a guidance note which recommended the use of desktop studies. These, it said, could be done by laboratories accredited by the UK Accreditation Service in the absence of actual fire test data for the system on a building.

Within a year, however, it had weakened this guidance to allow “a suitable qualified fire specialist” to carry them out. It included no advice as to what suitable qualifications might be.

But even this position got lighter. In 2016, the National House Building Council listed several common combinations of cladding and insulation which it believed could be signed off without the need for a desktop study.

This included Celotex RS5000 insulation and ‘Class 0’ aluminium composite material cladding: the exact combination used on Grenfell.

What now? While this may have seemed like a history lesson, these processes are being echoed today.

The BRE, which led the examination of Approved Document B that introduced large-scale testing for insulation, is chairing the working group ‘Quality Assurance and Products’ in the review of regulations being fronted by Dame Judith Hackitt.

The plastic insulation industry is heavily represented on the committee writing the new standard on desktop studies. Leaked notes from a meeting of Kingspan in September show it has been following a “strategy” to support the continued use of desktop studies and testing.

The government has promised to alter building regulations to “restrict” the use of desktop studies – but this is a far cry from ruling them out altogether. In the meantime, combustible insulation continues to be used, perfectly in line with regulations, on high-rise buildings up and down the country.

Update: at 12.30pm on 19 March:

This story was updated following further comments from a BRE spokesperson.

The BRE also provided the following statement, below:

It’s worth reiterating the facts in relation to the Grenfell Tower fire. The rapid spread of the fire at Grenfell was through ACM that had a combustible core. This was not a material of limited combustibility and the tests conducted by DCLG last summer showed that the cladding systems with this type of ACM rain screen failed in cladding systems with both mineral wool insulation as well as PIR insulation. And both tests failed very quickly.

The report misses the point that if a cladding system had been tested against BS8414 as a method to support use, then it would have failed precluding its use on a building over 18m in height. i.e. the regulatory system and BS8414 if properly followed would have fulfilled their intent by disallowing its use in the interest of the safety of people in and around the building as intended.

The evidence and facts are there for all to see – the number of fire deaths and injuries have been on a downward trend for the last 50 years and the improvements resulting from the research that BRE has undertaken has contributed significantly to this. The point of the large-scale test was (and still is) that cladding systems with their full design should be tested as they are intended to be used on a building. This is to provide a full understanding of how an actual system will perform. For example, the DCLG tests clearly showed that a material of limited combustibility insulation such as mineral wool still failed a full-scale test when a combustible core ACM is included.

There is not a single example of a fire in which a cladding system that has passed the BS 8414 test has resulted in fire spread on the outside of a building either here in the UK, in the UAE or in Australia where they also use this test method.

When Approved Document B was redrafted in the mid-2000s, we acted as a contractor for the Office of the Deputy Prime Minister (ODPM) and as the secretariat to provide them with the support that they needed to complete this very large task. At no time were any questions ever raised that questioned our competence, independence or ability to carry out this task. The stakeholders that engaged with this work never questioned our involvement. We are just one of a widespread array of stakeholders and experts who have been part of the evolution of the building regulations and associated guidance.

The section on Peter Field’s comments in 2000 could be read to suggest that a key motivation for BRE to recommend full scale fire testing was because we had a vested interest in growing a market for this form of test because we were no longer part of government. This is unbalanced and we can state categorically that this was not the case.

In terms of keeping test results private, as a UKAS accredited test laboratory we are required by the accreditation standard to keep test results strictly confidential. If we do not, we risk losing our accreditation. And those manufacturers that have tests done are required to represent them accurately in information to underpin the use of their products. Not doing so is illegal and an infringement of trading standards law which is prosecutable if these test results are misrepresented, or if a manufacturer chooses to change the design or composition of the materials they use.

What we care deeply about is people and property safety and we have some of the very best and most experienced scientists in the world to help support the work on the development and implementation of standards and where necessary, their improvement and enhancement to keep them relevant to changing needs.

If BRE did not exist, who would carry out the research necessary to understand how fires develop and behave and how they impact on the built environment in order to keep people in the UK safe?