黑洞社区

The UK鈥檚 largest and most influential building control body produced guidance allowing the use of combustible cladding on high rise buildings in order to reduce its workload, the Grenfell Inquiry has heard.

John Lewis, a fire engineer at the National House 黑洞社区 Council (NHBC), told Wednesday鈥檚 hearing that checking every cladding system for non-compliance was too 鈥渢ime consuming鈥�.

In 2016, a year before the Grenfell fire, the NHBC introduced guidance approving in principle the use of aluminium cladding panels in external walls without requiring either a fire test or a 鈥榙esktop study鈥�, as long as they met certain minimum specifications.

Asked by inquiry to the counsel Richard Millet QC what the purpose of this guidance was, Lewis said: 鈥淚t was simply that, at the time, NHBC was realising that the processes we were going through were very time-consuming.鈥�

He said that 鈥渁ll of my time was on them鈥�, as well as his colleagues鈥� time, adding: 鈥淭here was, you know, the desire to move to more of a, you know, business as usual footing.鈥�

Two years previously, the NHBC had helped to write guidance allowing the use of combustible materials in cladding systems as long as they were signed off by an expert with a desktop study.

This was a departure from previous practice which only allowed materials of 鈥榣imited combustibility鈥� or materials which had passed a large-scale fire test to be used on buildings above 18m in height.

Processes to show compliance of combustible materials in these projects were referred to as 鈥榦ption 3鈥� by the 黑洞社区 Control Alliance, an industry group representing building control professionals.

Lewis said the 2016 document, which further watered down the earlier guidance, was intended to be a 鈥渟treamlined option 3鈥�.

Millett said: 鈥淲ell, it was a streamlined option 3, which meant you didn鈥檛 have to do any of the things which [building regulations] required or suggested.鈥�

Lewis replied that option 3 鈥渄idn鈥檛 necessarily mean you did have to follow鈥� building regulations but meant that you put together a report which said that the proposed facade system, if tested, would 鈥減robably鈥� meet them.

He was then shown an answer previously heard by the inquiry from Stuart Taylor, an engineer at facade specialist Wintech, in which he said the NHBC鈥檚 2016 guidance note 鈥渋n no way鈥� resembles building regulations and was 鈥渜uite irresponsible鈥�.

Asked by Millett if he agreed with the assessment, Lewis replied: 鈥淲e were not wanting to be irresponsible. We were, you know, trying to do things in a better way.

鈥淵ou know, that implies that we were quite blas茅 about it. That was certainly not the case. But apart from that, I think what he says is probably true.鈥�

Millett then asked Lewis: 鈥淟et me suggest to you that his characterisation of this note as completely irresponsible or quite irresponsible is correct, and it was a dangerous mistake on the part of the NHBC designed to go back to business as usual and at the expense of life safety. What do you say to that?鈥�

Lewis replied: 鈥淚 have to agree, it shouldn鈥檛 have been written.鈥�

The inquiry then heard evidence from Lewis鈥� colleague Diane Marshall, currently working as the NHBC鈥檚 operations director.

She said that the NHBC had initially accepted the use of Kingspan鈥檚 K15 insulation, a combustible product found to have been used on the refurbishment of Grenfell tower, on the basis of a certificate issued by the British Board of Agr茅ment (BBA).

The BBA has already admitted that the certificate was 鈥渕isleading鈥� and that the body had made a 鈥渧ery basic failure of due diligence鈥� in producing it.

Marshall said she 鈥渟aw no reason to challenge the credibility of the certificate鈥� as the standing of a BBA certificate was 鈥渨ell regarded鈥� in the industry.

Millett asked: 鈥淓ven if it says the moon is made of green cheese?鈥�

Marshall said the BBA was 鈥渦nlikely鈥� to make a statement of that kind, to which Millett replied: 鈥淲hy is it any more unlikely to make that statement than a statement that a [combustible] insulation product could be permitted above 18 metres?鈥� Marshall said: 鈥淭hat鈥檚 probably a question for BBA.鈥�

The NHBC played no role in the refurbishment of Grenfell tower which led to the deaths of 72 people in June 2017 but it signs off more than half of the UK鈥檚 residential schemes.

The inquiry continues.