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O'Donnell54548  
#1 Posted : 20 November 2020 13:26:32(UTC)
Rank: Forum user
O'Donnell54548

Watching the tv last night there was a report, yet again, on the Grenfell enquiry. The central theme of the piece was about the number of high rise flats identified as having unsafe cladding, and the ongoing question about who has to pay to have this removed and replaced. From the report it appeared that the overall cost will run into 100's of millions. The question being asked was "should this come from the Government, building owners or the leaseholders?".

Now let me be absolutely clear about this, I am not an expert on sprinkler systems, and am definetly not an engineer, but would it not be possible to fit some form of external sprinkler system to such buildings?

If possible I would imagine that this would be a much more economical solution, but as I say I am no expert so its over to all the experts out there, what do you think?

And just to be clear, I would like to hear from those who think it could be made to work rather than a long list of reasons why it won't. 

Thank you

peter gotch  
#2 Posted : 20 November 2020 13:42:06(UTC)
Rank: Super forum user
peter gotch

O'Donnell

To deal with your specific question and not suggest why this could not work......

I think it would probably require a HUGE header tank on the roof which would probably require strengthening of the roof and quite probably the structure underneath.

Add flame and smoke detection and make sure that the drainage is upgraded to cope with a flood down the side of a building and it could work.

thanks 1 user thanked peter gotch for this useful post.
O'Donnell54548 on 22/11/2020(UTC)
Roundtuit  
#3 Posted : 20 November 2020 14:09:01(UTC)
Rank: Super forum user
Roundtuit

If external sprinklers were a viable resolution do you not think these would have already been installed?

Pouring water down the outside of a "rainscreen" does not reach any flame travelling within the air space behind.

The "unsafe" aspect of cladding a combination of materials used AND the manner in which they have been installed.

Anything within the throughwall construction omitted or badly installed e.g. fire stops needs correcting which of necessity involves stripping back to gain access.

2019 a major housebuilder had quite a lot of remedial work of a similar nature

https://www.theguardian.com/business/2019/dec/17/persimmon-accused-of-building-houses-with-intolerable-fire-risk

Roundtuit  
#4 Posted : 20 November 2020 14:09:01(UTC)
Rank: Super forum user
Roundtuit

If external sprinklers were a viable resolution do you not think these would have already been installed?

Pouring water down the outside of a "rainscreen" does not reach any flame travelling within the air space behind.

The "unsafe" aspect of cladding a combination of materials used AND the manner in which they have been installed.

Anything within the throughwall construction omitted or badly installed e.g. fire stops needs correcting which of necessity involves stripping back to gain access.

2019 a major housebuilder had quite a lot of remedial work of a similar nature

https://www.theguardian.com/business/2019/dec/17/persimmon-accused-of-building-houses-with-intolerable-fire-risk

Messey  
#5 Posted : 22 November 2020 18:50:43(UTC)
Rank: Forum user
Messey

As Roundtuit has mentioned, the combustible insulation is covered by a rain screen, which as the name suggests is in place to keep water away from the insulation and wall. It may well burn away, and the rain screen at Grenfell did exactly that. But that added to the heat output and perhaps the abilty for a sprinkler/drencher to work effectively.

Add to that the wind at any level above the 5th floor would make things tricky, as would any updraft from a fire below. Then there's the frost and low temperatures. OK, the drencher could be a dry pipe system, but then you may need fire detection within the cladding and a whole new world of complication - plus space for the plumbing and weight bearing structure for water tanks.

Its best to get rid of the cladding and replace it. IMHO, this cost of this MUST NOT fall to the leaseholder of the flat. As far as I see, if I bought a car, a washing machine or PC and it was found to have been constructed with materials not fit for purpose, I would expect Volkswagen, Indesit or Lenovo to pay for the replacement 

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O'Donnell54548 on 22/11/2020(UTC)
O'Donnell54548  
#6 Posted : 22 November 2020 21:41:38(UTC)
Rank: Forum user
O'Donnell54548

Originally Posted by: Messey Go to Quoted Post

As Roundtuit has mentioned, the combustible insulation is covered by a rain screen, which as the name suggests is in place to keep water away from the insulation and wall. It may well burn away, and the rain screen at Grenfell did exactly that. But that added to the heat output and perhaps the abilty for a sprinkler/drencher to work effectively.

Add to that the wind at any level above the 5th floor would make things tricky, as would any updraft from a fire below. Then there's the frost and low temperatures. OK, the drencher could be a dry pipe system, but then you may need fire detection within the cladding and a whole new world of complication - plus space for the plumbing and weight bearing structure for water tanks.

Its best to get rid of the cladding and replace it. IMHO, this cost of this MUST NOT fall to the leaseholder of the flat. As far as I see, if I bought a car, a washing machine or PC and it was found to have been constructed with materials not fit for purpose, I would expect Volkswagen, Indesit or Lenovo to pay for the replacement 


As I mentioned in my original posting, I am not an expert or engineer. However I am not aware of any research or feasibility studies looking at alternatives to removing/replacing the cladding in light of the size and expense of the task. I was making only one potential solution, and asked that people look at "how can we do this" rather than "this cannot be done". 

For example; instead of one huge header tank, why not individual tanks on each floor?

As for Rounduit's comment " if external sprinklers were a viable resolution do you not think these would have already been installed? ", I am glad he was not around when some poor guy was trining to invent the wheel!

Roundtuit  
#7 Posted : 22 November 2020 23:19:40(UTC)
Rank: Super forum user
Roundtuit

Originally Posted by: O'Donnell54548 Go to Quoted Post
I am glad he was not around when some poor guy was trining to invent the wheel!

Given the scale of the problem, the number of engineers globally including fire protection specialists I considered it a fair observation to make after all the years since this and previous similar incidents.

You freely admit you are not an engineer but choose to frame a hypothetical question which prevents the consideration of physical engineering limitations in the design of a building.

So just to continue the "why not" - to install such an exterior solution would necessitate the item you are trying to avoid i.e. the physical stripping out of the existing cladding to ensure adquate and suitable flow of water behind the rainscreen. In doing so you create a chimney behind the rainscreen that draws heat and flame upwards (to prevent a fire being drawn up the exterior of a building we...do the exact opposite and install fire stopping which also prevents the flow of water).

A tank on each floor - which flat(s) are you sacrificing? These developments are built and refurbished on maximising the available (chargeable) floor space within the dimensions as set by planning control.

The reason the studies do not exist are that people trained in such matters have not run a fools errand. If you or your employer would like to sponsor some university research I am sure Nottingham Trent or similar could generate a paper on the matter.

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O'Donnell54548 on 23/11/2020(UTC), O'Donnell54548 on 23/11/2020(UTC)
Roundtuit  
#8 Posted : 22 November 2020 23:19:40(UTC)
Rank: Super forum user
Roundtuit

Originally Posted by: O'Donnell54548 Go to Quoted Post
I am glad he was not around when some poor guy was trining to invent the wheel!

Given the scale of the problem, the number of engineers globally including fire protection specialists I considered it a fair observation to make after all the years since this and previous similar incidents.

You freely admit you are not an engineer but choose to frame a hypothetical question which prevents the consideration of physical engineering limitations in the design of a building.

So just to continue the "why not" - to install such an exterior solution would necessitate the item you are trying to avoid i.e. the physical stripping out of the existing cladding to ensure adquate and suitable flow of water behind the rainscreen. In doing so you create a chimney behind the rainscreen that draws heat and flame upwards (to prevent a fire being drawn up the exterior of a building we...do the exact opposite and install fire stopping which also prevents the flow of water).

A tank on each floor - which flat(s) are you sacrificing? These developments are built and refurbished on maximising the available (chargeable) floor space within the dimensions as set by planning control.

The reason the studies do not exist are that people trained in such matters have not run a fools errand. If you or your employer would like to sponsor some university research I am sure Nottingham Trent or similar could generate a paper on the matter.

thanks 2 users thanked Roundtuit for this useful post.
O'Donnell54548 on 23/11/2020(UTC), O'Donnell54548 on 23/11/2020(UTC)
stevedm  
#9 Posted : 23 November 2020 08:06:52(UTC)
Rank: Super forum user
stevedm

sorry I thought this was a forum for opening up discussion not closing it down...despite the yet again angry responses from some....you need to dig a wee bit deeper into the fire engineering of buildings and although sprinklers may not be the most suitable option for building weight and loading etc which would add huge cost...there may be other options which I think is what you are trying to get at...in explosion engineering we use a number of different protective measures to prevent or mitigate the event...so why can't we apply the same principles here?...detection, suppression, human behaviour, fighting the fire...are the core items that need to be considered...same as any offshore platform for instance...so what other suppression systems could be retrofitted may be the question?  That would be more costs efficient?...perhaps removal of the existing cladding and applying fire retardant coatings?...I am sure there will be a number of negative replies but perhaps if we all pause, take a breath and solve the problem rather than coming up with reasons not to solve it the safety profession wouldn't get the rep it does....  :)

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aud on 23/11/2020(UTC), O'Donnell54548 on 23/11/2020(UTC)
achrn  
#10 Posted : 23 November 2020 08:19:23(UTC)
Rank: Super forum user
achrn

Originally Posted by: stevedm Go to Quoted Post

in explosion engineering we use a number of different protective measures to prevent or mitigate the event...so why can't we apply the same principles here?


I'm not sure what you're trying to say here.

It seems to be something along the  lines of 'Engineers in all other sectors look at what's the most effective way to solve a problem, but those in fire engineering must be uniquely stupid and haven't done that'.  Is that it?

Also, there is no point at all in any discussion of feasibility if you prohibit any reference to why something doesn't work.

Let's discuss how to beat Covid.  I propose rubbing a mixture of lemon juice and egg-white on everyone's nose.  Discuss, but I don't want to hear any suggestions about how it won't work. I would like to hear from those who think it could be made to work rather than a long list of reasons why it won't.

stevedm  
#11 Posted : 23 November 2020 08:30:36(UTC)
Rank: Super forum user
stevedm

...yep I knew it would come….only trying to open the debate not close it down….maybe you are right?...I  don't know but why can't we ask a question and use our collective experience to debate a problem?...everyone has different experiences and views to put to it,  so instead of blaming covid for everything and putting your fingers in your ears and shouting blah blah blah...doesn't improve your intellect...intelligent debate does ;)

achrn  
#12 Posted : 23 November 2020 08:49:04(UTC)
Rank: Super forum user
achrn

Originally Posted by: stevedm Go to Quoted Post

...yep I knew it would come….only trying to open the debate not close it down….maybe you are right?...I  don't know but why can't we ask a question and use our collective experience to debate a problem?...


We can, but not by refusing to acknowledge why a proposed solution won't work.

A question is asked.  The question is (roughly) 'would this work?', but apparently only responses that say yes are allowed in the discussion. No-one is permitted to mention any reasons why this 'solution' wouldn't work.  You think this approach 'opens up the debate'?

OK then:  Yes it's a great solution.  Carry on.

https://www.youtube.com/watch?v=BKorP55Aqvg

stevedm  
#13 Posted : 23 November 2020 08:56:14(UTC)
Rank: Super forum user
stevedm

Originally Posted by: stevedm Go to Quoted Post

sorry I thought this was a forum for opening up discussion not closing it down...despite the yet again angry responses from some....you need to dig a wee bit deeper into the fire engineering of buildings and although sprinklers may not be the most suitable option for building weight and loading etc which would add huge cost...there may be other options which I think is what you are trying to get at...


Oh dear lets not read the post then...lets just troll...just trying to improve your intellect... ;)

Perhaps if people like yourself had been more vociferous in their responses to their bosses when the building was going up people wouldn't have died..

A Kurdziel  
#14 Posted : 23 November 2020 10:11:45(UTC)
Rank: Super forum user
A Kurdziel

If we apply the Swiss Cheese model to this whole mess, we can see that there were a whole series of failures not just one, which led to all of those people losing their lives.

  1. There was no real overall “risk assessment” about the cladding: what type to use? how to fit it and what impact it would have on the fire safety of the building. Different people knew bits of information by they had no idea of how THAT cladding would work in THAT building if there was a fire. They all assumed that someone else would pick it up the issues and sort of them before it was fitted.
  2. There did not seem to be any sort of check that the cladding was properly fitted.
  3. Nobody explained to the building’s management or the Fire brigade how this might change the way the building would have to operate
  4. Finally the fire brigade continued to stick with a “stay put policy” based on totally wrong assumption of what the cladding would do in a fire.

What we need to do is look at how this system can be put right. Adding new complications such as an external drenching system would simply create more opportunities for cock-up eg ensuring that the water supply is frost protected and does not leak; making sure that the detection system is reliable enough (if we go for a dry system) and that you don’t have false alarms when it will [expletive deleted] water all over the building unnecessarily,. It might be that this approach is the best approach but that requires an in-depth analysis of the cost-befits of this or any other approach.

 

Roundtuit  
#15 Posted : 23 November 2020 10:27:28(UTC)
Rank: Super forum user
Roundtuit

Originally Posted by: stevedm Go to Quoted Post
Perhaps if people like yourself had been more vociferous in their responses to their bosses when the building was going up people wouldn't have died.

Many of the high rise buildings such as the one in question were not originally built with cladding - their outer surface being concrete a non-combustible material. At time of build every flat would have been its own protection compartment.

Imposition of retrospective energy efficiency requirements "Eco-Design" necessitated post-build installation of cladding systems to these properties frequently breaking the compartmentalisation.

The fire performance of one installation is currently subject to a public enquiry at which to date we have heard -

the outer skin manufacturer knew of flammability issues with their aluminium sandwich product but chose not to communicate this to the market

the insulation manufacturer testing included a non-combustible board omitted from the report a designer would use

the installaton company "value engineered" against the original proposal

their employees had little knowledge of materials or fire protection e.g. miss-understanding the purpose of an EPDM waterproofing strip at a window opening

the cavity stopsocks that were installed were not done so correctly

Like every incident once again the alignment of a series of unfortunate events.

When people talk about "the same cladding" invariably the truth is they are discussing the same type of outer skin RainScreen - I have watched the news showing local high rise being stripped back and the insulation layer is not the organic material involved with the enquiry but mineral wool (again another non-combustible material).

Problem is now the blame game has started no one is willing to do anything other than "belt and braces" - perhaps that is the answer to the OP no one is willing to risk something that is untried and untested.

thanks 2 users thanked Roundtuit for this useful post.
A Kurdziel on 23/11/2020(UTC), A Kurdziel on 23/11/2020(UTC)
Roundtuit  
#16 Posted : 23 November 2020 10:27:28(UTC)
Rank: Super forum user
Roundtuit

Originally Posted by: stevedm Go to Quoted Post
Perhaps if people like yourself had been more vociferous in their responses to their bosses when the building was going up people wouldn't have died.

Many of the high rise buildings such as the one in question were not originally built with cladding - their outer surface being concrete a non-combustible material. At time of build every flat would have been its own protection compartment.

Imposition of retrospective energy efficiency requirements "Eco-Design" necessitated post-build installation of cladding systems to these properties frequently breaking the compartmentalisation.

The fire performance of one installation is currently subject to a public enquiry at which to date we have heard -

the outer skin manufacturer knew of flammability issues with their aluminium sandwich product but chose not to communicate this to the market

the insulation manufacturer testing included a non-combustible board omitted from the report a designer would use

the installaton company "value engineered" against the original proposal

their employees had little knowledge of materials or fire protection e.g. miss-understanding the purpose of an EPDM waterproofing strip at a window opening

the cavity stopsocks that were installed were not done so correctly

Like every incident once again the alignment of a series of unfortunate events.

When people talk about "the same cladding" invariably the truth is they are discussing the same type of outer skin RainScreen - I have watched the news showing local high rise being stripped back and the insulation layer is not the organic material involved with the enquiry but mineral wool (again another non-combustible material).

Problem is now the blame game has started no one is willing to do anything other than "belt and braces" - perhaps that is the answer to the OP no one is willing to risk something that is untried and untested.

thanks 2 users thanked Roundtuit for this useful post.
A Kurdziel on 23/11/2020(UTC), A Kurdziel on 23/11/2020(UTC)
aud  
#17 Posted : 23 November 2020 14:05:53(UTC)
Rank: Super forum user
aud

Thanks to achrn for adding another favourite to my Youtube list.

Grenfell was not just about the cladding.

The similar fire in the Australian Lacrosse building in 2014 did not have casualties, although fire raced up the outside of the clad walls to the 21st floor. All 400 residents were evacuated by the fire service. The building had (internal) sprinklers. As did similar buildings in other countries which had massive external cladding fires. 

Sprinklers - just ordinary standard internal ones - save lives. They suppress smoke, they cool the areas whilst people escape, they prevent or deal with internal fire which starts from the external cladding. They prove their worth over and over. Yet still we (UK) don't fit or retrofit them - and they are feasible and affordable in the grand scheme.

I have just rewatched The Great British Housing Crisis - BBC documentary of 1984. Well worth looking at - Youtube obviously - for all sorts of reasons, but very relevant to any discussion around this.

O'Donnell54548  
#18 Posted : 23 November 2020 18:51:42(UTC)
Rank: Forum user
O'Donnell54548

Originally Posted by: stevedm Go to Quoted Post

sorry I thought this was a forum for opening up discussion not closing it down...despite the yet again angry responses from some....you need to dig a wee bit deeper into the fire engineering of buildings and although sprinklers may not be the most suitable option for building weight and loading etc which would add huge cost...there may be other options which I think is what you are trying to get at...in explosion engineering we use a number of different protective measures to prevent or mitigate the event...so why can't we apply the same principles here?...detection, suppression, human behaviour, fighting the fire...are the core items that need to be considered...same as any offshore platform for instance...so what other suppression systems could be retrofitted may be the question?  That would be more costs efficient?...perhaps removal of the existing cladding and applying fire retardant coatings?...I am sure there will be a number of negative replies but perhaps if we all pause, take a breath and solve the problem rather than coming up with reasons not to solve it the safety profession wouldn't get the rep it does....  :)


Thank you stevedm, at least you seem to have gotten the gist of my posting. The H&S profession has such a negative reputation because it is seen as having a "you can't do that" mantra.

We seem to have become robots, all churning out the same tired statements and doggidly following ACOPs and British Standards. These discussion forums are full of people asking for copies of all kinds of stuff from RA formats to training presentations. When did we lose the ability to think for ourselves?

The Health & Safety at Work Act was a radical, far reaching, innovative piece of legislation. It provided the scope for employers and professionals to get creative and build H&S systems specific to their workplace. 

After 25 years in the H&S profession, retiring this year as a CMIOSH, I have come to the conclusion that we have wasted this opportunity, and now anyone who goes "off piste" is ridiculed and thought incompetent.

My thanks to all who have contributed, negative and positive.

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stevedm  
#19 Posted : 24 November 2020 09:55:48(UTC)
Rank: Super forum user
stevedm

O'D and what you see here and have listed is one of the reasons I left IOSH...

..I thought this quote was particularly apt...

'Jane Duncan, chair of the RIBA Expert Advisory Group on Fire Safety, said: ‘I’m pleased to see the government commit to addressing some of the urgent issues in UK buildings safety regulations and welcome proposals to extend requirements for sprinklers and the ban on combustible materials.

This year will mark the third anniversary of the Grenfell Tower Fire, and far too little has changed since the tragedy,’ she added.....'

stevedm  
#20 Posted : 25 November 2020 10:58:03(UTC)
Rank: Super forum user
stevedm

sorry...you know when you have an itch you can't scratch...just reading through the RIBA comments and the new bill and amendments to Approved Doc B...seems to me they are mandating sprinklers in building over 18m (although RIBA want buildings over 11m to be included) and the new bill seems to concentrate on enforcement and responsibility which we pretty much had already...amendments to the RRFSO to give back powers that we took away from Fire Service?...new gov enforcement unit..if the old method worked will the new one (?)...there is a stream that seems to point this away from builders...but aren't they the ones most likely to cut corners?...the architects spec the material...I am not sure I am drawing any conclusions just yet as I probably need more coffee but I haven't seen much on new research only on how bad ACM is....just expanding my knowledge as it is relevant for me with occupied buildings in high hazard plants and conflict zones...

A Kurdziel  
#21 Posted : 25 November 2020 11:27:27(UTC)
Rank: Super forum user
A Kurdziel

It’s not  that they there were no rules is just that it is not clear who was responsible for applying them

https://www.bbc.co.uk/news/uk-54792108

Once a upon a time the council or who ever would come up with the design and make sure it was bult up to their specification but now everything is dispersed with different companies responsible for narrow areas and the issue of the cladding fell between the gaps.

The council had handed over management of the buildings to a separate company, Their main interest was in using taxpayers money to improve thermal efficiency  of the building’s insulation but they had no idea of how to do that so they hired a company to look at that  but they had no idea about the fire safety implications and the building contractor had no idea either and did not realise the  implications of changing the spec. the supplier of the cladding was not honest about what they were supplying and expected the contractors to tell them what they wanted etc. That’s what happens in our modern lean working world, where corner cutting is built in.

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stevedm on 27/11/2020(UTC)
stevedm  
#22 Posted : 26 November 2020 09:35:23(UTC)
Rank: Super forum user
stevedm

yep..I get the responsibility and accountability bit but still say that has always been there...the engineering and design is sparking my investigative nature....the original design specification, included both a fire resistant core and zinc outer cladding...this was changed I assume due to cost, to material that had the same fire rating... still digging...I know I won't find anything new but I will fully understand the implication both from an engineering perspective and the resultant legal issues...

stevedm  
#23 Posted : 26 November 2020 10:20:02(UTC)
Rank: Super forum user
stevedm

ok...only part way through the initial inquiry report...and found an old ISOH thread 2016 about uPVC windows.....here's a question - the window in the flat deformed and then the flame (~60-300kw) impinged on the cladding and associated make up...so why are we not talking about better windows/window rating for buildings over 11m?...can we get windows with better fire resistance than 30min?

off to model the flat fire it in CFAST  :)

stevedm  
#24 Posted : 26 November 2020 12:55:44(UTC)
Rank: Super forum user
stevedm

I can see that I am on my own here... :)  

roundt - get it and helpfull post in the context of my research...but again are we not missing some key facts?  The cladding is being focussed on was more combustable than the original but not a different fire rating...I can't find any mention of changing the fire rating assessment process?...which I assume the architect signed off on..(now dissolved) the point of the fire was the fridge which then melted the window and fan which then impinged on the insulation and then cladding...which once it has been set alight will just burn with ever increasing intensity...so although I get it is complex series of 'unfortunate events'...so how do we prevent it again?...I know the 'experts' are giving opinions and all we have seen so far is accountable person etc..so how do we put the engineering control in place to avoid this tragic series of human errors?

sorry vested interest my daughter has just started studying architecture and one question we have debating is how can we apply the lessons from Grenfell and still produce great architecture... or what should we be telling our future architects?   

ok I am going to leave it now as I feel I am dancing on my own at the end of the night sober.... 

A Kurdziel  
#25 Posted : 26 November 2020 13:06:41(UTC)
Rank: Super forum user
A Kurdziel

SteveM 

When the final report is published -they seem to be asking the right questions, we’ll all have a look and see what they say. Hopefully it will something about stopping the buck passing making sure people can’t sign off on something without really understanding the full implications of what they are saying.

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stevedm on 26/11/2020(UTC)
Roundtuit  
#26 Posted : 26 November 2020 13:47:33(UTC)
Rank: Super forum user
Roundtuit

https://www.gov.uk/government/publications/fire-safety-approved-document-b

The intersting read is section 5.21

This is mirrored in section 19.2 of BS 9991:2015 Fire safety in the design, management and use of residential buildings – Code of practice

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Roundtuit  
#27 Posted : 26 November 2020 13:47:33(UTC)
Rank: Super forum user
Roundtuit

https://www.gov.uk/government/publications/fire-safety-approved-document-b

The intersting read is section 5.21

This is mirrored in section 19.2 of BS 9991:2015 Fire safety in the design, management and use of residential buildings – Code of practice

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CptBeaky  
#28 Posted : 26 November 2020 14:04:32(UTC)
Rank: Super forum user
CptBeaky

Originally Posted by: stevedm Go to Quoted Post

ok...only part way through the initial inquiry report...and found an old ISOH thread 2016 about uPVC windows.....here's a question - the window in the flat deformed and then the flame (~60-300kw) impinged on the cladding and associated make up...so why are we not talking about better windows/window rating for buildings over 11m?...can we get windows with better fire resistance than 30min?

off to model the flat fire it in CFAST  :)


I work for a company that manufactures windows. There are no official fire resistance ratings for uPVC (or aluminium) window frames, that I am aware of. Strangely enough you can get timber framed with fire resistance, but these have to also have specfic glass units installed, using specialist tapes. And then only be fitted by a registered fitter.

uPVC tends to melt between 150 - 220°C (dending on a few factors). Aluminum frames would be better, melting at around 660°C, but then would also need the glass units to be fire resistant.

Basically it comes down to cost, weight etc.

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stevedm on 26/11/2020(UTC)
stevedm  
#29 Posted : 26 November 2020 14:15:23(UTC)
Rank: Super forum user
stevedm

appreciate the responses so far ...it help to understand another industry fully...

AK - yep get it and yes they are but doesn't stop us asking others...

RT - I am more interested in the fact they are exclude non load bearing - i.e. the cladding - from the requirement for fire resistance...in 5.3 (c)...

uPVC windows thanks...I found some that were 120min FR (although the website sent my phising filter into overdrive) but at £2.5k per unit yes pricey...

all of this has an effect on how the FS respond and fight the fire...because for all intents and purposes stay in place is still ok with a structured evac...??

  

Kate  
#30 Posted : 26 November 2020 16:46:16(UTC)
Rank: Super forum user
Kate

In case you don't already get this, the BBC do a weekly podcast on the Grenfell Tower Inquiry with highlights of the witness questioning, summaries of the evidence and interviews with experts in various areas to explain the issues touched on.  Well worth listening to for the detail of what went wrong and how (and who is blaming who, with very few witnesses accepting any responsibility for any of it).

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stevedm on 27/11/2020(UTC), MikeKelly on 27/11/2020(UTC)
stevedm  
#31 Posted : 27 November 2020 12:04:41(UTC)
Rank: Super forum user
stevedm

  • Prevention 

So far there are a number of issues under the selection and installation of the associated parts from the windows to the external cladding.  Which I am sure the inquiry will at least attempt to solve.  Which will also include how do you deal with using old electrical equipment in the fire design of a building and indeed should you?

Does the fire rating of products need to be thoroughly reviewed to ensure that it is fit for purpose? (the architects spec'd cladding was the same FR as the ACM yet they all seem to agree the architects spec was significantly safer)

Does Human Factors in build design need to be covered more effectively at each stage?  We do evacuation HF but don't we need to build that into the design? I can't see that it is covered anywhere from concept to breaking ground...

from Part B of Schedule 1 of the Building Regulations 2010. ‘Requirement Internal fire spread (linings) B2 (1) To inhibit the spread of fire within the building, the internal linings shall: a. adequately resist the spread of flame over their surfaces; and b. have, if ignited, a rate of heat release of a rate of fire growth which is reasonable in the circumstances’… Should we be asking for a Quantitative Risk Assessment rather than the more subjective qualitative?

  • Detection

Early detection (I am talking about in the fabric of the building now not the compartment i.e. the external walls or internal conduits, as I am not sure you can fully control the residents although some sort of detection is a given in the compartment) combined with active fire protection in those spaces, could that have prevented the spread after all it started on the 4 floor...?  again suitable mitigation for older buildings to retrofit?  vesda (although that is only as good as the commissioning?)

  • Control & Mitigation

Mmm  not sure yet…

  • Response – Occupants / RFS

I think time to evacuate is covered as there is enough modelling out there to do it justice…might now consider lifts in the evac plan which makes all of the components of a lift safety critical?  So in SIL terms a requirement to be at least SIL 2 or better? Wow that is a real ask…I have read through BD2466, but again it is asking for a qualitative risk assessment (QDR) (BS7974) rather than a quantitative…is that the right way to go bearing in mind I am now saying that they are safety critical elements and their survivability is key to the evacuation…which also brings in SCE validation…?

In the investigation into the World Trade Center collapse it was found that in the 16 minutes before the impact of the second aircraft, 27% of those who evacuated WTC2 used the lifts for part of their escape route. In addition, the investigation found some evidence that the flow rate from WTC2 during these 16 minutes was approximately twice that for WTC1 (where only stairs were available for evacuation)....just supporting better use of lifts..

I should probably shut up now...I thank O'D (I think) fopr making me use this subject for reflective practice - to see where the gaps where in my knowledge/skills/experience...to better do my job  :)

thanks 2 users thanked stevedm for this useful post.
MikeKelly on 27/11/2020(UTC), peter gotch on 28/11/2020(UTC)
Messey  
#32 Posted : 28 November 2020 01:48:49(UTC)
Rank: Forum user
Messey

In a previous life I was a firefighter in the London Fire Brigade and served at North Kensington in the 80s in which time I attended several high rise fires locally, including at Grenfell Tower. This was the pre refurbished Grenfell of course, and one serious fire was punching out of the windows of the flat as we arrived and licking up the facade.

But just like in fires at neighbouring blocks such as, Adair Tower (12 fl), Trellick Tower (33 fl), Norland House (22 fl) and many others, the Grenfell fire I attended scorched, blackened and spalled the concrete external facade but didnt ignite. It was concrete and hadnt yet been 'improved' by wrapping it in combustible plastics

Just like every high rise flat fire I attended, everyone stayed put in their flats during these fires- other than on the floor of orgin - and most were safe. One job at Trellick Tower did leapfrog up 3 floors due to high winds, but even then, we caught it as the external facade was non combustible and despite a near miss, nobody was hurt

So although there is a place for  sprinklers in some very tall blocks of flats, as long as the external walls are non combustible, there is no need for external drenchers, header tanks or external flame detection.

Lets not overthink this. 

It akin to having a regular brake defect on a car, and just making the bumpers bigger instaed of replacing he brakes!!!

thanks 3 users thanked Messey for this useful post.
stevedm on 28/11/2020(UTC), peter gotch on 28/11/2020(UTC), Kate on 30/11/2020(UTC)
stevedm  
#33 Posted : 28 November 2020 11:34:05(UTC)
Rank: Super forum user
stevedm

messy...agree...however due to the range of FR (one was decided safer but the same FR) for products is that not the issue?  FRS would follow the Operational guidance based on as you say the assumption...and although the gov and some are focussing on sprinklers (which is probably driven by the insurers because in my experience insurers demand it in these sort of circumstances) if we sorted out all the other component parts to this including the human factors so the layers of protection actually work and safety integrity is maintained?...is that not it or I am thinking too utopian?...I come to this as I always do with no pre-conceived ideas....it is only by over thinking we get step change ;)

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A Kurdziel on 30/11/2020(UTC)
A Kurdziel  
#34 Posted : 30 November 2020 09:39:19(UTC)
Rank: Super forum user
A Kurdziel

Messy is probably right we could just leave the flats alone and not put on any potential flammable external cladding but that would leave us with loads of cold damp miserable housing which nobody wants to live in. When these were built back in the sixties, keeping them warm was not seen as an issue. Most had a gas supply and so they could use some form of gas heating. North Sea gas had just arrived, and the future looked bright. Then Ronan Point happened, and the government response was to remove the gas supply from all council high rise blocks. Heating now relied on inefficient electric heating.  When the energy crises of the seventies hit, people could no longer afford the high electric bills. They keep heating to a minimum and the flats become dank cold high rise hovels. What we should have done was demolished then and started again with new purpose built housing but that has not happened, and we are left with trying to keep these 50 year old block habitable by spending the least amount of money.

thanks 1 user thanked A Kurdziel for this useful post.
Kate on 30/11/2020(UTC)
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