“令人信服的證據”證實Grenfell塔樓不符合建築法規
Inquiry finds "compelling evidence" Grenfell Tower did not comply with building regulations
由專築網麻雀，小R編譯
調查發現，在翻新的過程中，Grenfell塔樓的外部增加了隔熱層、覆層和裝飾面層，這些做法不符合建築法規。
這份長達1000頁的報告已被調查主席Martin Moore-Bick公佈。它展示了調查的第一階段的發現和建議。
第一階段檢查了倖存者和急救人員的證據和證詞，確定了2017年6月夜間，當時一幢高層建築中的一場大火導致71人喪生，其中大部分人因火勢蔓延而被困在煙霧環繞的建築外牆內。
Moore-Bick說：“有力的證據表明，建築物的外牆設計不符合《 2010年建築物條例》附表1的B4（1）要求。”
“考慮到建築物的高度、功能和位置，它們無法抵抗火勢的蔓延。相反，它們促進了火勢的蔓延。”
1984年《建築法》和2010年《建築法規》規定，“建築物的外牆應能夠抵抗火勢蔓延，對現有建築物的改動不應違反建築法規”。
火勢通過塑料窗框蔓延至外牆層
Grenfell塔樓建於1974年，作為議會大廈，從2015年到2016年花費了數百萬英鎊進行翻新。
具有聚乙烯芯的鋁複合材料的（ACM）防雨板和由聚異氰脲酸酯（PIR）泡沫製成的隔熱板用於圍繞現有的鋼筋混凝土牆，從而作為新外牆。
2017年6月14日凌晨1：14，第一批消防人員抵達16號樓的廚房，那裡是起火點。
在調查的第二階段，將對建築面層系統的翻新計劃進行更徹底的檢查，但是專家和倖存者作了關於火的起源和蔓延的證詞。
Moore-Brick說：“儘管我本來並不打算在第一階段得出有關該塔是否符合《建築規範》的結論，但我認為既然與建築的外牆有關，那就應該確定是這個問題我。”
“我接受《建築規範》的構建最終是一個法律問題，並且有令人信服的證據表明在這種情況下未滿足要求B4（1）。否則就違反了法規規定。”
專家得出結論，大火最有可能進入建築面層，其主要是通過標準電氣設備大火產生的熱煙使uPVC窗框變形而造成的。
專家總結說，在ACM面板被點燃之前，大火點燃了窗框周圍的可燃材料。
裝飾性的塑料造成了火勢的蔓延
火焰在不到20分鐘的時間內就在ACM防雨層內垂直向上蔓延到塔上，聚乙烯芯（一種最常用於製造塑料袋和包裝的可燃合成熱塑性聚合物）成為了燃料。
面層後面的隔熱板中的PIR和酚醛泡沫也是導致火勢蔓延的原因之一。
塔頂裝飾層中暴露的聚乙烯在燃燒時融化並滴落，進一步引發建築物下方的大火，火勢同時也向上蔓延。這就是大火在建築物的所有面上蔓延的方式，直到整個塔樓都從外面開始燃燒。
覆層已固定在建築物頂部的預製混凝土體量上。除了裝飾，它們沒有其他功能。 愛丁堡大學的建築學教授，報告的專業見證人Luke Bisby說，當建築頂部燃燒時，它就像一個“線性熔斷器”，將火勢向水平蔓延。
在新的面層和保溫層與舊的混凝土牆之間留有空隙，以使建築的面層中能夠通風。 但是在大火的夜晚，這個空腔讓火點燃了能夠助燃的材料。
安裝了條形止活帶縫隙，為了在起火時它們會膨脹並阻塞縫隙。 但是，專家說，在火焰位於ACM面板內部的火災中，阻隔屏障幾乎沒有用。
當大火的燃燒熱量導致窗戶無法開啟時，建築物外部的火勢蔓延到公寓。廚房的抽氣扇變形並移位，這也是導致大火進入內部的原因。同時一些防火門失靈或被撐開。
建築行業和政府的消防安全標準將被調查
Moore-Bick說，一場大火在三小時之內從垂直蔓延到水平蔓延，併吞沒了一座高層建築。
“考慮到這一點，我打算在調查的第二階段檢查用於外牆的材料，熱塑性聚合物材料，例如聚乙烯，及其管理規定。使用這種方法已經足夠識別和控制向下和水平以及垂直火焰蔓延的潛在危險。”
“我還將研究建築行業的人員和負責制定消防安全標準的相關人員對熱塑性聚合物所帶來的特殊危險的瞭解情況。”
面層磚製造商Arconic和建築翻新承包商Rydon在報告的現階段對Moore-Brick做出有關建築法規的判斷表示反對。但是，Moore-Brick堅持認為Grenfell塔樓的外牆不能抵抗火勢蔓延的證據太明顯了。
Moore-Brick說：“無論出於何種原因，我都認為沒有合理的理由來爭辯建築物的外牆符合要求B4（1）。因此，沒有充分的理由取消報告，這僅是不言而喻的結論。”
接下來，相關人員將探討負責安裝覆蓋系統和替換窗戶的人員如何讓Grenfell塔樓滿足建築法規。
“我感到滿意的是，儘管有許多不同的因素在起作用，但火焰如此迅速地蔓延到整座建築物的主要原因是帶有聚乙烯芯的ACM面板的存在，該面板的燃燒速度快，熔化並充當了著火的源頭。它成為火災的助燃劑。”
Moore-Brick尚未就面層提出任何建議，但政府已禁止使用類似的面層材料，具有類似系統的建築物現在可以申請政府撥款，以幫助拆除和更換面層。
提前撤離塔樓可以挽救更多生命
儘管當晚有227人逃離了塔樓，但Moore-Bick的報告還說，如果撤離塔樓的決定早些做出，那麼可以挽救更多的生命。
該報告強調了倫敦消防隊沒有明確撤離塔樓的要求，塔樓沒有疏散計劃，事故指揮官也沒有接受過高層建築外牆火災蔓延的救援培訓。
如果撤離的決定在凌晨1：30到1：50之間做出，那麼樓梯仍相對無煙，則可以挽救更多的人。
Moore-Bick說：“我敏銳地意識到當晚值班的人員面臨著前所未有的局面，他們沒有做好充分的準備，人員和系統都被災難的規模淹沒了。”
“首先應該說的是，在最悲慘的情況下，控制室中的人員和部署在事件現場的人員以極大的勇氣和奉獻精神做出了回應。”
Insulation, cladding and decorative fins added to the exterior of Grenfell Tower during refurbishment made it noncompliant with building regulations, the inquiry into the disaster has found.
The 1,000 page report has been published by inquiry chair Martin Moore-Bick. It presents the findings and recommendations from the first stage of the inquest.
The first phase examined evidence and testimonies of survivors and first responders, establishing a timeline of the night in June 2017 when a fire in a high-rise building killed 71 people, most of whom had become trapped in the smoke-filled tower as fire spread around the external walls.
"There was compelling evidence that the external walls of the building failed to comply with Requirement B4(1) of Schedule 1 to the Building Regulations 2010," said Moore-Bick
"They did not adequately resist the spread of fire having regard to the height, use and position of the building. On the contrary, they actively promoted it."
The Building Act 1984 and the Building Regulations 2010 states that externals walls of buildings should be able to resist the spread of fire, and that alterations made to existing buildings should not make the building noncompliant.
Fire spread to cladding via plastic window frame
Built in 1974 as council housing, Grenfell Tower underwent a multi million pound refurbishment from 2015 to 2016.
Aluminium composite material (ACM) rainscreen panels with a polyethylene core and insulation panels made with polyisocyanurate (PIR) foam were used to create a new exterior wall around the existing reinforced concrete walls.
The fire was in the cladding system before the first firefighters arrived in the kitchen of Flat 16, where the fire started, at 1.14 am on 14 June 2017.
The refurbishment scheme that introduced the cladding system will be examined more thoroughly in the second phase of the inquiry, but experts and survivors testified about the origin and spread of the fire.
"Although it was not originally my intention to reach conclusions in Phase One about the tower’s compliance with the Building Regulations, I can see no good reason why that question should not be determined now so far as it relates to the external facade," said Moore-Brick
"I accept that the construction of the Building Regulations is ultimately a question of law and there is compelling evidence that requirement B4(1) was not met in this case. It would be an affront to common sense to hold otherwise."
Experts concluded that the most likely way the fire got into the cladding was through a hole made when hot smoke from a standard electrical appliance fire made the uPVC window jamb deform.
Combustable insulation materials around the window frame then ignited, experts concluded, before setting fire to the ACM panels.
Unusual spread of fire caused by decorative plastic crown
It took less than 20 minutes for flames to spread vertically up the tower within the ACM rainscreen, fuelled by their cores of polyethylene – a combustible synthetic thermoplastic polymer most commonly used for making plastic bags and packaging.
PIR and phenolic foam in the insulation boards behind the cladding also contributed to the fire rate and spread.
Exposed polyethylene in the decorative crown that topped the tower melted and dripped as it burned, starting additional fires further down the building, which also spread upwards. This was how the fire travelled across all the faces of the building, until the whole tower was burning from the outside in.
Fins of cladding had been fixed at the top of the building on the pre-cast concrete architectural crown. They served no function beyond decoration. As the crown burned it acted like a "linear fuse" spreading the fire horizontally said Luke Bisby, an architecture professor at the University of Edinburgh and expert witness for the report.
Gaps had been deliberately left between the new wall of cladding and insulation, and the old concrete wall, to allow ventilation and any water that got in to dry out. But on the night of the fire this cavity allowed the fire to reach the materials that fuelled it.
Cavity barriers with strips that expand in the event of fire and block the gaps had been installed, but the investigation also found they were poorly fitted and had gaps between them. However, experts said that in a fire where the flames were inside the ACM panels, such as Grenfell Tower, the barriers would have been little use halting the spread of the flames.
The fire on the outside of the building got into the flats when the heat caused the windows to fail. Extractor fans in kitchens deformed and dislodged, also letting the fire in. Some fire doors failed or were propped open.
Construction industry and government fire safety standards will be investigated
A fire that spreads horizontally and can engulf a high-rise building in under three hours is unusual, said Moore-Bick.
"With that in mind, I intend in Phase Two of the Inquiry to examine (among other things) the extent to which the regime for testing materials intended for use in external walls (including thermoplastic polymer materials such as polyethylene) and the regulations governing their use were, and are, adequate to identify and control the potential dangers from downward and horizontal as well as vertical flame spread," he said.
"I shall also examine what was and should have been known, both by those in the construction industry and by those in central government responsible for setting fire safety standards, about the particular dangers posed by thermoplastic polymers."
Cladding manufacturers Arconic and the refurbishment contractor Rydon pushed back against Moore-Brick making a judgement about building regulations at this stage in the report. However, Moore-Brick insisted the evidence that Grenfell Towers walls did not resist the spread of fire was all too obvious.
"I can see no rational basis for contending that the external walls of the building met requirement B4(1), whatever the reason for that might have been," said Moore-Brick. "There is therefore no good reason for deferring to a later report what is no more than a self-evident conclusion."
Next the inquiry will look at how those responsible for the installation of the cladding system and replacement windows – including Arconic, Rydon, and architects Studio E – were satisfied that Grenfell Tower met building regulations.
"I am satisfied that, although many different factors played a part, the principal reason why the flames spread so rapidly up the building was the presence of the ACM panels with polyethylene cores, which had high calorific value, melted and acted as a source of fuel for the growing fire," he said.
Moore-Brick has made no recommendations about cladding yet, but the government has already banned similar cladding materials and buildings with similar systems can now apply for a government fund to help get it removed and replaced.
More lives could have been saved by an early tower evacuation
Although 227 people escaped the tower that night, Moore-Bick's inquiry also said that more lives could have been saved if the decision to evacuate the tower had been made earlier.
The report highlighted how the London Fire Brigade failed to recognise that compartmentalisation had failed and the tower needed to be evacuated. There was no evacuation plan for the tower, and incident commanders had not been trained on how fires on high rise building facades can spread.
If the decision to evacuate had been made between 1.30am and 1.50am, when the stairways were still relatively smoke-free more people could have been saved.
"I am acutely conscious that those who were on duty that evening were faced with an unprecedented situation for which they were not properly prepared and that both personnel and systems were overwhelmed by the scale of the disaster," said Moore-Bick
"It is right to say at the outset that those in the control room and those deployed on the incident ground responded with great courage and dedication in the most harrowing of circumstances."
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