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Grenfell Tower fire


SteamyTea

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Yes, that's the original architects detail (it's where I got it from earlier in this thread).  At some point both the cladding specification and the insulation specification seems to have been changed, but that change seems to have been made with approval, as Harley Facades referred to the aluminium composite cladding on their (now deleted) web pages.

 

The aluminium composite rain screen was almost certainly cheaper than the zinc; currently zinc is around $2500/tonne, aluminium alloy around $1500/tonne.  In addition, the aluminium composite panels may well have been significantly lighter, so giving an additional possible cost saving on fasteners.

 

I can't believe that the aluminium composite was substituted for the originally specified zinc without some sort of sign off, probably by three or more parties.  Whether they considered the altered fire risk I don't know, but from what's been revealed or uncovered so far I doubt they did.

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I would pay at least some attention to Hammond until proven ill-informed, as he spent part of his career some years ago developing Iirc Doctors' Surgeries for the NHS.

 

So he has some hinterland and contacts to find out, though one jump away.

 

Otoh he does sometimes use slightly apocalyptic language.

 

Ferdinand

Edited by Ferdinand
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1 hour ago, Ferdinand said:

I would pay at least some attention to Hammond until proven ill-informed, as he spent part of his career some years ago developing Iirc Doctors' Surgeries for the NHS.

 

So he has some hinterland and contacts to find out, though one jump away.

 

Otoh he does sometimes use slightly apocalyptic language.

 

Ferdinand

 

 

Having heard the interview, he didn't say that it was illegal, he said that he thought it might be banned here, when told by Andrew Marr that it was banned in other countries.  In fact its not banned here at all (yet), so this seems to be another case of the media playing fast and loose with the facts.  What a surprise..................

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1 hour ago, Ferdinand said:

I would pay at least some attention to Hammond until proven ill-informed, as he spent part of his career some years ago developing Iirc Doctors' Surgeries for the NHS.

 

So he has some hinterland and contacts to find out, though one jump away.

 

Otoh he does sometimes use slightly apocalyptic language.

 

Ferdinand

Otoh

Erm...what?

Iirc

Ditto

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8 hours ago, Tennentslager said:

Otoh

Erm...what?

Iirc

Ditto

 

Oops.

 

8 hours ago, Nickfromwales said:

On the other hand

If I recall correctly ;)

 

 

YTR.

 

:D

 

We need an acronym dictionary. For me iirc is when I have not absolutely bottomed something I am asserting but it is more than opinion. In this case I could not immediately come up with a list of his projects for the NHS but had found newspaper bios referencing the activity.

 

F

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Interesting news:

 

http://www.standard.co.uk/news/london/sixtyeight-flats-in-2bn-luxury-block-to-be-given-to-families-whose-lives-were-devastated-in-grenfell-a3569876.html

 

Puts the average cost of construction for each flat at just below £150K. 

 

It'll be interesting to see how some of the residents react to this news, given the critical comments that have been made about rehousing them.  Whilst the local council response does seem to have been quite poor, there does seem to be a lot of unrealistic expectation in terms of how quickly that number of people can be re-homed and where.

 

 

 

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I understand they are being offered the affordable apartments that the developer was required to include to get PP. I doubt they will look like the show apartments in the photos as these go for £1.6 to £5m according to the Times. Apparently they aren't finished yet but the council have relaxed the hours the developer can work to help speed them up.

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Someone interviewed on the news said "too little too late" FFS what did they expect the council to do? anticipate the fire and have a stock of replacement flats ready sitting empty?  It was just lucky these are available now to re house some of those affected.

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A statement by someone from Scotland Yard on BBC just now said that both the "Insulation and tiles" used in the cladding has failed a combustion test carried out by the BRE.

She also said samples of the insulation "combusted soon after the test started" and that the "initial test on the cladding tiles also failed the safety tests".
 

Not sure if this link will work for long but skip to 10:42..

 

http://www.bbc.co.uk/iplayer/live/bbcnews

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That fits well with everything I've looked at and researched about this fire.  There are many issues involved, each of which on its own may not have been a major hazard, but when combined they created what amounted to a "perfect storm".  The insulation seems to be Class O rated for spread of fire, making it apparently suitable for use on an external wall of a building with multiple dwellings.  The same goes for the aluminium composite panels, they also seem to have a Class O rating.

 

The problems that I've found, just from a few hours of digging around, seem to be:

 

-  The insulation fire resistance rating doesn't seem to have taken into account the effect of the ventilation gap, and the consequent chimney created between the insulation and the outer rain screen cladding.

 

-  The openings in the building don't seem to have adequate, if any, fire stops, so a fire coming out of a window was able to set light to the material on the outside of the building.

 

-  The window surrounds and cills were made from PVC, which may have provided the initial fuel source outside the building that allowed the fire to penetrate to the insulation and cladding system.

 

-  The PIR RS5000 foam gives off flammable gases when heated, and when combined with a source of fire that was directed and funnelled up behind the rain screen cladding, this created what amounted to a large blow torch burning upwards, with a very strong updraft from the chimney effect.

 

-  Once the fire was established behind the rain screen cladding, the thin inner layer of the rain screen aluminium composite burned away, exposing the normally sealed-in polyethylene foam core.  This then added further fuel to the fire, allowing the temperature to increase to the point where the aluminium itself started to burn. 

 

-  At this point, the fire was probably incapable of being extinguished by any appliances that were available.  The fire spread vertically at such a speed that it quickly got above the reach of any appliances.  Additionally, once the aluminium was burning the fire would have been hard to suppress with water alone.

 

-  The high temperature on the outside of the building breached the windows to the other dwellings, allowing the fire to penetrate inside the building.

 

Apart from the combination of design and material specification failings that created the fire risk, there also seems to have been major failings in the fire safety assessment and planning for the whole building.  I can find no reference to any fire risk assessment made after the cladding was fitted (the last is dated 2015, before it was fitted). 

 

The building control register shows the status of the building as "Completed, Not Approved". 

 

There are several stories from residents of the fire alarms not working. 

 

The evidence from escaping residents also indicates that the supposed new smoke clearance system for the stair well failed to operate, as smoke in that area, and on the landings, seems to have been the major cause of loss of life, by stopping people from escaping. 

 

The fact that the management company still believed that the building was "fire proof", and that they were still giving advice to residents to stay in their flats, shows that there was a major failure to properly assess the changed fire risk.

 

All told, there seems to have been criminal negligence, by several responsible parties, as this was far from being an unknown risk - there have been many facade fires over the past few years, enough for anyone undertaking a project like this to have had the external fire risk near the very top of their risk register.

 

Edited by JSHarris
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So what about the HotPoint fridge freezer that caused the fire?  Will we be having a total recall of all defective appliance!  ? Will we be adding appliance manufacturers to the list of those criminally responsible?

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I suspect, and it's only a guess, it wasn't that the new smoke clearance failed per se, if it's like the one I get involved with but that it drew in smoke filled air. This if the stair pressurization fans were on the roof. Guessing (again) at some weird cyclic effect with smoke under pressure being forced into the stairwells, corridors and I guess flats. 

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51 minutes ago, Onoff said:

I suspect, and it's only a guess, it wasn't that the new smoke clearance failed per se, if it's like the one I get involved with but that it drew in smoke filled air. This if the stair pressurization fans were on the roof. Guessing (again) at some weird cyclic effect with smoke under pressure being forced into the stairwells, corridors and I guess flats. 

 

The details specification for the new smoke clearance system doesn't seem to be easily available, or at least I've not yet been able to find it (I'll keep lokking).  The system we had on the office and lab building that was a part of my last programme before I retired, didn't have an fans.  There were smoke exit louvres on a structure a bit like a pyramid, on top of the roof, over the main atriums of the building.  These louvres were automatically opened in the event of the fire alarm going off, and the ground floor fire exit doors also automatically opened.  The natural internal chimney effect created a really powerful updraft in the building, drawing clear air in from ground level and letting the smoke escape from the top of the internal atriums.

 

17 minutes ago, Crofter said:

Thanks @JSHarris for that very thorough and persuasive analysis. You put the media to shame!

 

Thanks for the kind words, I've spent a few tens of hours over the past week trying to gather data on what most probably happened, using a causal analysis method that an acquaintance, Peter Ladkin ( https://causalis.com/10-about/20-people/), developed some years ago.  We were both involved in looking at the cause of a fatal accident, and I thought his Why-Because methodology was pretty powerful.  I've used it a few times since, when asked to look at accidents by insurance companies, but this tragic fire was a good excuse to apply it to a big accident, with lots of events, as it's a very powerful way of sifting out non-causal events, and weighting the probability of any event being in the primary causal chain.

Edited by JSHarris
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When I heard the cladding had failed the fire test I thought "No S**t Sherlock"

 

There is talk of a corporate manslaughter charge if they can find enough evidence.  I am sure the Wayback machine will some in handy for that. I expect a lot of computers will be confiscated and a lot of file undeleting going on.

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5 minutes ago, ProDave said:

When I heard the cladding had failed the fire test I thought "No S**t Sherlock"

 

There is talk of a corporate manslaughter charge if they can find enough evidence.  I am sure the Wayback machine will some in handy for that. I expect a lot of computers will be confiscated and a lot of file undeleting going on.

 

I have copies of pretty much every document of web page that was in the public domain and has since been taken down.  I doubt I'm alone, others will have done much the same, I'm sure.

 

The web of responsibility looks to be so wide that I think there could potentially be dozens of prosecutions brought, as the failings range from misleading data used to obtain BBA certification (sadly something that's far from new) through to what seems to be a complete failure to undertake any form of coherent risk analysis.

 

One telling point was a report on the news at lunchtime that reporters were unable to obtain any information from a few government departments about things from fire testing of products through to the numbers of fridge freezers that might be affected.  The idiots haven't yet realised that government doesn't have this information - responsibility for testing, inspection and regulation have all been devolved away from government and placed with the manufacturers and construction industry, or private sector inspection companies.  A consequence of that is that government has very little knowledge of what's been going on - they only find out where there's a tragic event like this.

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It seems likely that there would already have been an air handling unit in the roof top plant room, and that may have been modified as a part of the refurbishment, but with no indication of this on the planning drawings, as these only show the new ASHPs on the roof.  The refurbishment wasn't carried out fully in accordance with the planning drawings, either, the cladding material was changed from zinc to aluminium and some minor details seem to have been changed, perhaps as non-material changes.

 

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Could an unintended consequence of the lack of joined up thinking here not be that if a smoke vent system was fitted it would actually have drawn in smoke and flames from the fire outside the building and made things worse.

 

I am no expert on these things but presumably it would have been designed on the basis that any fire is contained to one flat and the smoke in the rest of the building has to be removed. For a larger fire could the large amounts of air that this kind of system could be moving actually start to fuel and spread the fire?

 

The lack of focus on evidence for how to stop this happening again and the involvement of politics is saddening.

 

Last night on Question Time someone was adamant that the cause of the fire was austerity. This makes no sense as if they had not spent £10m cladding the building then this would not have happened.

 

We should await the report but it seems that the devastating loss of life was caused by a number of failings and the general lack of care and incompetence that is seen time and time again.

 

There are calls to rehouse everyone in similarly clad buildings. This is not really practical. I believe that as a stop gap measure if simply all alarms were checked to make sure that they work, the advice was changed to make sure people leave the building was evacuated as quickly as possible and we ensured that fire escapes were kept clear then we would have mitigated most of the risk and this would give time for the more long term solution of replacing the cladding. There are calls to fit sprinklers in all tall buildings, it is not clear that would have helped here or is practical. I am concerned that it is a call for the most expensive, complicated solution so that then the government can be blamed for not doing it.

 

 

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I think that it's possible that a fire door may have been left open somehow, perhaps as people in a flat above the fire that initially spread up the corner of the building, evacuated, and that smoke may then have been drawn into the central stair well that way.  There is good video of the fire up to around an hour after it started, and at that time the main entrance to the building and the ground floor is completely smoke free.  Firefighters can be seen walking around in the lobby area in that video.  This suggests that the smoke was being drawn in from either the top of the building, or from one of the flats that was burning in that corner.

 

Here's the video: https://www.pscp.tv/w/1RDGlZqozBDxL

 

The balance between smoke removal and spread of fire is, according to the fire officer that inspected the new building I was involved with, one of time.  Apparently smoke kills far more people than fire, and small fires create enough smoke to kill lots of people.  So, the emphasis is on getting rid of the smoke, even if that does make the fire spread faster, as clearing smoke saves more lives overall.  I'll admit to finding this odd at first, but the argument presented by the fire officer for putting the priority on a good alarm system and an effective smoke removal system was compelling.

Edited by JSHarris
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