Tower block fire - london

[LOAM]

However the bbc is saying the zinc and aluminium boards offer the same fire protection

It just highlights the issues with class rating for surface spread of flame, it ignores what is behind the surface. Look at the BBA certificate for Raynobond. Class 0 rating issued for PE products based on testing of the FR product.



http://www.bbacerts.co.uk/CertificateFiles/45/4510PS1i1.pdf

 

[Maccapacca]

Zinc and aluminium is a red herring. The Reynobond above only refers to the metal finish to the sandwich panels not what actually caught fire which was the insulation behind.

 

[Hagar]

Zinc and aluminium is a red herring. The Reynobond above only refers to the metal finish to the sandwich panels not what actually caught fire which was the insulation behind.

Quite, the melting point of zinc is lower than aluminium. Class 0 refers to surface resistance to fire.

 

[wildman]

Quite, the melting point of zinc is lower than aluminium. Class 0 refers to surface resistance to fire.

so technically speaking the pannels met the requirements then. If they didn't then i go back to my previous comments and people are going to Jail and this was murder because it can only mean that substandard materials and materials that didn't meet the specs were knowingly used ?

 

[C.R.A.Z.Y]

Zinc and aluminium is a red herring. The Reynobond above only refers to the metal finish to the sandwich panels not what actually caught fire which was the insulation behind.

Well the whole lot was burning/on fire after a short time (Both cladding & Insulation)

The point is the cladding if it had used Zinc would have provided a significantly stronger protection for the insulation behind it. The super cheap ally+polyethylene cladding provided little to no fire protection for the insulation behind.

Also the more expensive Zinc cladding didn't have the stupidly flammable basic polyethylene core, instead it used mineral-rich “fire-retardant polyethylene core”

 

[wolfie138]

Does it?

"Documents show the zinc cladding originally proposed was replaced with an aluminium type, which was less fire resistant, saving nearly £300,000."

yes. it does.

 

[wildman]

Well the whole lot was burning/on fire after a short time (Both cladding & Insulation)

The point is the cladding if it had used Zinc would have provided a significantly stronger protection for the insulation behind it. The super cheap cladding provided little to no fire protection for the insulation behind.

Not really, Zinc has a singificantly lower melting point than aluminium.

Zinc = 420°C melting point
Aluminium = 660°C melting point

so technically speaking the zinc would have failed sooner exposing what ever insulation was contained behind it. However if the argument is that the original panels had a zinc honeycomb core rather than a PE one then that's a different story.

 

[robfosters]

http://www.standard.co.uk/news/lond...r-meeting-amid-furious-protests-a3576391.html

holy crap

council ordered to allow media into the meeting by high court, so council cancelled it ? That stinks of cover up

Nicholas Paget-Browns position is completely untenable. He should step down as he will never be able to escape this tragedy.

 

[wildman]

Nicholas Paget-Browns position is completely untenable. He should step down as he will never be able to escape this tragedy.

yes, but didn't he go on record saying he has no intention of resigning ? seems wierd that he has made such a grand faux pas and no one seems to be holding him or the council to account on this issue of this meeting and the way they have treated the residents, families and victims.

 

[C.R.A.Z.Y]

Not really, Zinc has a singificantly lower melting point than aluminium.

Zinc = 420°C melting point
Aluminium = 660°C melting point

so technically speaking the zinc would have failed sooner exposing what ever insulation was contained behind it. However if the argument is that the original panels had a zinc honeycomb core rather than a PE one then that's a different story.

They installed ally cladding that used cheap very flammable polyethylene core, the Zinc ones originally spec'd used a Fire RESISTANT polyethylene core.


Below is what was specc'd to be used and decisions were mad to use a cheaper product, had the below cladding been used the fire would almost certainly not have spread as quickly as it did.



Also common sense comes into things, do you honestly think the safer more fire retardant cladding is going to be the cheapest one sold ??

 

[wildman]

They installed ally cladding that used cheap very flammable polyethylene core, the Zinc ones originally spec'd used a Fire RESISTANT polyethylene core.


Below is what was specc'd to be used and decisions were mad to use a cheaper product, had the below cladding been used the fire would almost certainly not have spread as quickly as it did.

That's a misnomer

polyethylene by its very nature and materials it is made from is not fire resistant to the extent that would prevent what you saw in Grenfell. What would make it resistant is the material it is clad in that protects it. A pure zinc coated core would offer less fire protection that one in Aluminium based on basic material science. Yes you can treat PE polymers to increase fire resitance, but if they are then sandwiched in a metal that has a very low melting point then it's a waste of time

If your theory is correct then are you also saying that this was actually murder, and there was clear intent by both the council and the contractors to kill these people by knowingly putting substandard materials on the building ?

 

[C.R.A.Z.Y]

The cheap cladding burns more easily and quickly
The more expensive cladding less easily and slower due to the high mineral content

Are you honestly suggesting that using the more expensive and fire resistant cladding would have had no effect on the speed at which the fire spread ??

 

[Maccapacca]

They installed ally cladding that used cheap very flammable polyethylene core, the Zinc ones originally spec'd used a Fire RESISTANT polyethylene core.


Below is what was specc'd to be used and decisions were mad to use a cheaper product, had the below cladding been used the fire would almost certainly not have spread as quickly as it did.



Also common sense comes into things, do you honestly think the safer more fire retardant cladding is going to be the cheapest one sold ??

You're getting it mixed up. The original uses a .5mm zinc on a core. It still would have needed the 70 odd mm of insulation behind it which is what caught fire.

The cladding used was a 3 or 4mm aluminium stuck to the 70 odd mm of insulation.

The zinc / aluminium options is a non story. They could have still used the zinc and the insulation they did use and the result would have still been the same

 

[ubersonic]

However the bbc is saying the zinc and aluminium boards offer the same fire protection

Read it again, "same official fire rating".

What that means is that the Zinc boards and the Aluminium reynobond PE used both had the same rating for protection against surface fire spread (as does the reynobond FR fire resistant version of the alu board). However surface fire spread means jack **** when your an insulation sandwich and your internal insulation is flammable.

This is the issue I was getting at, is that the insulation that makes up the core of the aluminium panel made it unsuitable for use on that building as per the regs, the FR version would have been fine (and prevented this disaster) as it's insulation material is fire resistant, if the Zinc version originally specified also had fire resistant insulation (and would have prevented the disaster) then it means whoever made that cost saving decision killed 80+ people.

 

[Maccapacca]

The cladding burnt from the insulation out not from outside in.

 

[ubersonic]

The cladding burnt from the insulation out not from outside in.

Indeed.

 

[wildman]

Read it again, "same official fire rating".

What that means is that the Zinc boards and the Aluminium reynobond PE used both had the same rating for protection against surface fire spread (as does the reynobond FR fire resistant version of the alu board). However surface fire spread means jack **** when your an insulation sandwich and your internal insulation is flammable.

This is the issue I was getting at, is that the insulation that makes up the core of the aluminium panel made it unsuitable for use on that building as per the regs, the FR version would have been fine (and prevented this disaster) as it's insulation material is fire resistant, if the Zinc version originally specified also had fire resistant insulation (and would have prevented the disaster) then it means whoever made that cost saving decision killed 80+ people.

so its murder then, because the council and the contractor knowingly used or allowed the use of materials that would ensure that if there was a fire these people would be killed ? This is what I am trying to determine. If they did this with full knowledge that it would go up like a firework then anyone that touched anything to do with that decision making process should be going to parkhurst for a minimum 15 year stretch for murder right ?

 

[C.R.A.Z.Y]

One of the cladding's purpose is to protect the insulation behind it, the fact the insulation was protected with cladding that had a horribly weak fire resistance meant that flames and heat was able to ignite the insulation far faster than it should have.

 

[ubersonic]

The zinc / aluminium options is a non story. They could have still used the zinc and the insulation they did use and the result would have still been the same

Wait, no, it would have been completely different, nobody would have died and the fire wouldn't have spread lol.

 

[Maccapacca]

One of the cladding's purpose is to protect the insulation behind it, the fact the insulation was protected with cladding that had a horribly weak fire resistance meant that flames and heat was able to ignite the insulation far faster than it should have.

You're getting awfully confused.