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RCI Feb 2018

Project1_Layout 1 07/05/CLADDING & SHEETING What lessons have been learned? Jonathan Evans, director of the MCRMA, and chief executive officer and chairman at Ash and Lacy, believes many questions remain unanswered in 032 FEBRUARY 2018 RCIMAG.COM Dame Judith Hackitt’s interim report into the Grenfell Tower fire I ’m concerned that Dame Judith’s proposed direction of travel outlined in her Building Regulations review interim report is away from the epicentre of the issue, and unlikely to satisfy the remit of reassuring people that everything is being done to ensure that a tragedy such as Grenfell does not happen again. The prevailing message in the report is a systemic failure of the regulatory system, but excluding Grenfell, statistics portray a significantly improving fire-related fatality rate against a convincing sample size. This does not suggest a completely broken system lacking in widespread competency. History suggests that this welcome progress is not jeopardised by future changes. Following the 1999 Garnock Court fire, the EFRA Committee believed that cladding systems should either be completely noncombustible, or subjected to full scale testing. This led to the introduction of the BS8414 test, but the consequences of that advice were badly thought through. The first failing, was when the Committee’s recommendations were summarised, large scale testing was included, but the associated recommendation of ‘completely non-combustible’ was not. Guidance was therefore not altered (and never has been) to exclude combustible cladding from non-tested systems, but the large scale test route opened the door for combustible insulation that was previously prohibited. This door blew wide open when the BCA decided that large scale testing was too onerous and introduced unregulated desktop studies. We now can’t close that door. Whilst Dame Judith identifies several pervasive industry weaknesses, such as the lack of clarity in accountability, conflicts of interest in fire risk assessments and building control must be addressed. The main focus should surely be the extraordinary nature of the Grenfell fire that caused statistics to become so distorted. It’s clear that the external walling system was a fundamental factor, and I hope Clive Betts’s MHCLG Committee pursues its line of questioning. The report’s opening paragraph states that an industry subsequently implied to be languishing in incompetency, failed to adopt the guidance requirement of limited combustibility for the cladding on Grenfell Tower. However, if you read the relevant section of the guidance, the requirements are not as complex, contradictory or convoluted as suggested. There is a requirement in Approved Document B Vol II clause 12.7 for ‘Insulation Materials/Products’ to be limited combustibility above 18m, but no equivalent requirement for external walls or surfaces (i.e the cladding). Diagram 40 e. shows that the requirement for external cladding material above 18m is Class 0 (national class) or Euroclass B-s3, d2 or better (European class): i.e combustible. Contrary to what Dame Judith says, it’s not difficult to understand why all of the buildings surveyed following the Grenfell fire had combustible cladding. Far from being widespread incompetency on behalf of the industry, it seems that this is in line with guidance requirements. Surely, this fundamental deficiency in the statutory documents needs investigating, and addressing as a matter of urgency if we are to avoid a repeat of Grenfell? This would have the benefit of unlocking the apparent stalemate involving property owners who have buildings that meet the requirements of Approved Document B, yet are clad in Class 0 polyethylene Aluminium Composite Material (PE ACM), which was proven in the DCLG tests to not comply with the actual Building Regulations? Furthermore, given the alarmingly rapid failure of the DCLG, BRE tests involving PE ACM (regardless of the insulation), why is there no clear instruction from the DCLG to property managers to strip tall buildings of this highly dangerous material? Desktop studies What is difficult to understand is why so many buildings surveyed had combustible insulation, which is clearly proscribed by clause 12.7? Given the paucity of large scale test passes published by the BRE at the time, presumably this situation has arisen due to ‘desktop studies’, which are now (according to the non-regulatory Building Control Alliance guidance) permissible by non-UKAS accredited organisations (in other words, ‘self-declared competent persons’). Surely in the context of the report remit, this is a huge concern, and the validity and/or legality of this route to compliance should be challenged? Desktop studies subvert the requirement of actual full scale test data as was originally intended by the 1999 EFRA Committee. The process of accommodating combustible materials has a number of consequences. It creates a disproportionate escalation in the complexity of the regulations and an associated likelihood of misinterpretation (deliberate or otherwise). Proscribing combustible materials would collapse the current disjointed system of rules, diagrams, tests and assessments into the simple, unambiguous guidance sought in the report. This needs to be investigated. Desktop studies and their problems owe their existence to combustible materials, as does large scale testing which appears to be deficient, and in particular, not cognisant of commonly found workmanship errors. Even if a combustible system passes a large scale test, combustible materials will burn, emitting significantly more deadly smoke and toxic fumes than a comparable limited combustibility system. Perhaps more than anything, the allowance of combustible materials does not reflect the strong feelings of the public who occupy these buildings. So far, there is a lack of engagement with the public, and a dangerous preoccupation with the opinions of industry professionals with commercial interests. Whilst the public may not possess fire engineering expertise, their ability to weigh the pros and cons of an argument to use combustible materials should not be underestimated. This all begs the simple question: ‘Why shouldn’t we simply ban all combustible materials from tall building external walls?’ (if necessary within an achievable timescale). So far, there is no presentation of a convincing case not to make this proportionate step, that I feel it would be broadly welcomed by the public.


RCI Feb 2018
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