Final Grenfell Fire Disaster Report
The Grenfell Tower disaster in 2017 is now covered in two voluminous reports.
Grenfell Tower suffered a disastrous high-rise fire in June 2017, more than 7 years ago. There were 72 killed in the horrors of the blaze, by the fire and poisonous gases evolved by the fire, and from other related injuries.
Grenfell memorial wall. By London Remembers, 2024
The building was a city council rental apartment block, designed in 1968 and finished in 1974 according to the then valid standards. That’s important, because the building was then considered fire-proof enough to use the ‘stay in place’ principle for a danger situation. That principle was not changed even after the building was modernized and the exterior cladding was added. Until renovation in 2015-2016 the exterior remained as originally conceived and approved, with raw concrete elements visible on the facade.
In the late 1960es and 1970es, the particular architectural style of Brutalism was very popular in the United Kingdom, mainly for utilitarian, low-cost social housing expressing some sort of socialist principles. It spread to other regions around the world, and was very similar to architecture for communal housing in Eastern Europe. It soon began to decay and was not well regarded any more, later in the century. Some building were of course better than others and a few obtained protected status, but in general, it was low quality without concern for details and built of low quality materials. Concrete is generally considered a good choice of material for the exterior of buildings, the ‘climate screen’ that protects the building and its inhabitants from wind and weather.
However, concrete comes in different qualities, and an effective climate screen must be well designed and built in order to work as desired. Grenfell Tower was not good at withstanding the weather, and there were creaks and worn surfaces all over. The choice with this type of building is demolition or, if the supporting structure is intact, refurbishing throughout, including the facade. In the case of Grenfell, the facade was not replaced but covered with an outer skin. Behind the outer skin, a ventilated gap and a layer of isolation foam behind it. It is not an unseen way to go, but not as a long-perspective, durable solution. These two, the non-evacuation principle and the stick-on facade renovation in combination were very unfortunately the basis for an absolute disaster. And the choice of materials, we will see shortly.
The first inquiry report was published in October 2019 and “set out to examine in detail the course of events on the night of 14 June 2017 with a view to identifying with as much confidence as possible what had taken place during the period between the outbreak of fire in the kitchen of Flat 16 at 00.54 and the escape of the last survivor at 08.07 that morning.”
Report 1, page 557: “23.52 In the light of the video evidence itself and the expert evidence summarised above, none of which was challenged, 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.”
What is concluded here is that the fire spread rapidly up and down the facade because of the materials. The outer panels (ACM) were of plastic, that burnt and melted. The melted, burning plastic spread the fire downwards and the high temperatures itself ignited the insulation foam. Part of this was also the gap behind the panels, that acted as a funnel to feed the fire with oxygen and spread the flames.
This, in combination with the lack of evacuation was behind the disaster.
Report 1, page 587: “27.9 The absence of an operational evacuation plan was a major omission in the LFB’s preparation for a fire at a building such as Grenfell Tower, but, since there was no attempt to carry out a managed evacuation of the building, it is less significant than the absence of any training for incident commanders in how to recognise the need for evacuation. That absence in turn reflects a failure to recognise the risk of fire taking hold on the outside of modern buildings. Several LFB witnesses said in one way or another that they did not understand what was happening as the fire spread up the building and that buildings “should not behave like that”. That reflected a failure to educate firefighters in the dangers associated with combustible cladding systems.” People on the upper floors called to ask when they would be evacuated and were told to stay put.
The report no. 2, just out, discusses the way leading to the disaster in more detail and with many interesting observations on standards, lack of compliance with standards, and lack of quality control with engineering and construction works. Without taking a too opinionated view on it, we can say it is impressive and thorough, but also very disappointing. So much work to do, so much to correct in mindset, approach and management of building practices and standards for this type of buildings. ”1.3 In Phase 2 we have set out to answer the question that has been at the forefront of many people’s minds: how was it possible in 21st century London for a reinforced concrete building, itself structurally impervious to fire, to be turned into a death trap that would enable fire to sweep through it in an uncontrollable way in a matter of a few hours despite what were thought to be effective regulations designed to prevent just such an event? There is no simple answer to that question, but in this report we identify the many failings of a wide range of institutions, entities and individuals over many years that together brought about that situation.”
Plastic
For most ordinary people, it will still be difficult to comprehend why plastic is still an approved building material, at all. It has become very popular with architects and builders to use exterior panels that are basically a thin sandwich of plastic foam between a thin aluminium sheet on the outside and plastic foil on the inside. These cladding panels are still in use in many countries world wide. However, most countries have restrictions so that the panels can only be used in the lower 1, 2 or 3 levels. Not for the complete facade up to level 24 or higher.