Internally insulating solid walls for better U Values

[John D v2.0]

They also originally stipulated some sort of community heating system, but this was later changed to gas boilers in individual flats

That's simply not true, there was a new gas boiler installed in the basement for the tower, and the existing old gas boilers were kept for the finger blocks outside the tower.
What was installed in the individual flats were heat interface units which took metered heat from the main circuit and put it into the flats radiator circuit.
The individual flats had their own gas supply from when the block was built, that was used for cooking.

crucially, the fact that there was a gap between the insulation and the original fabric of the building high I believe was related to the way the new windows had been installed. Essentially the gap (which had inadequate fire breaks)acted like a chimney, allowing the fire to spread very quickly up the outside of the building.I believe the window frames melted due to the intense heat.

Actually the gap was needed as it was a ventilated rain screen nothing to do with the windows, the problem with the cladding was actually determined to be the aluminium/pe cladding which melted and dripped down while burning, therefore setting light to the rest of the cladding. As you mention there were also no functional fire breaks into and throughout the void, the ones that were installed were not suitable for the location, and many were missing or incorrectly installed.
I recommend anyone interested read the executive summary of the first stage report, as there is so much misinformation and speculation going around, and the report is more accurate and has basis in the evidence painstakingly gathered so far.

 

[John D v2.0]

It is shocking that nobody has been prosecuted for Grenfell

The investigation is still ongoing, it's crazy the amount of evidence they have to gather and interpret to make a case, when prosecutions happen they have to stick in court as you can guarantee the accused will have the best lawyers to question things.
So far only the first stage of what actually happened has been investigated and most of the information needed for the inquests, but we need enough evidence to prove exactly who committed which offences and i hope we have that soon.
The legal system grinds it's gears slowly on these complex offences, steal a car and any lawyer can tie it up quickly, but break building regulations and cause a catastrophe and you need specialists.
Fingers crossed things will go well and this will be a lesson to never happen again

 

[whatsthenews]

It is shocking that nobody has been prosecuted for Grenfell. I remember reading a few years back about a landlord that went to prison for 6 months for breaching fire safety rules - there wasn't even a fire! There have been many similar cases.

Agreed. Another enquiry, just like Lakanal House. Councils getting away with it-AGAIN. Each Fire and rescue service has a public database of properties that have been served with Fire reg notices . Percentage of private v council owned properties is staggering and many services don't appear to EVER serve notices on councils. Of course who part funds the fire services? In Newcastle the head of the council is Vice chair of Tyne and Wear Fire and Rescue service.

 

[mikeey84]

Apologies, but I wanted to comment re Grenfell.
If you look at the BRE documents re green credentials/energy efficiency submitted as part of the planning application, they stipulated "rockwool or similar". I don't think the change to celotex was never officially amended, at least not in these documents

It's strange. Rockwool would likely be significantly cheaper, and permission to use it was given, despite it not hitting required U value, so I wonder why the hell they used PIR, which seems to a)be more expensive and b)not have been tested for compliance to the fire regs by the BRE

 

[whatsthenews]

That's simply not true, there was a new gas boiler installed in the basement for the tower, and the existing old gas boilers were kept for the finger blocks outside the tower.
What was installed in the individual flats were heat interface units which took metered heat from the main circuit and put it into the flats radiator circuit.
The individual flats had their own gas supply from when the block was built, that was used for cooking.


Actually the gap was needed as it was a ventilated rain screen nothing to do with the windows, the problem with the cladding was actually determined to be the aluminium/pe cladding which melted and dripped down while burning, therefore setting light to the rest of the cladding. As you mention there were also no functional fire breaks into and throughout the void, the ones that were installed were not suitable for the location, and many were missing or incorrectly installed.
I recommend anyone interested read the executive summary of the first stage report, as there is so much misinformation and speculation going around, and the report is more accurate and has basis in the evidence painstakingly gathered so far.

Thanks. That's not clear in the documents I've read. The 3 rd revision of the BREEAM Domestic Refurbishment Pre-Assessment document dated July 2013 states that heating for the tower would be via multiple communal Gas air source heat pumps (GAHP), but the 2nd version of the Sustainability and energy statement dated October 2012 states that the plan was for condensing gas combi boilers in flats.
Regarding the gap, it may have been required for ventilation of the rain screen, but it probably shouldn't have been
I'm sure there was an issue with the way the windows were installed and that after the refurb' there were window reveals and sills which weren't there previously. Perhaps they were "created" by the ventilation gap, and insulated with more flammable cladding.

 

[whatsthenews]

It's strange. Rockwool would likely be significantly cheaper, and permission to use it was given, despite it not hitting required U value, so I wonder why the hell they used PIR, which seems to a)be more expensive and b)not have been tested for compliance to the fire regs by the BRE

I think that's a question on many lips. Maybe we'll find out in Part 2.

 

[John D v2.0]

Regarding the gap, it may have been required for ventilation of the rain screen, but it probably shouldn't have been
I'm sure there was an issue with the way the windows were installed and that after the refurb' there were window reveals and sills which weren't there previously. Perhaps they were "created" by the ventilation gap, and insulated with more flammable cladding.

Yes having voids where fire can spread unseen and combustible external walls are key restrictions of the building regs, so although the void was necessary for keeping the structure dry, it should have had effective fire breaks at regular intervals. In my mind to maintain the properties of the rain screen and the fire integrity they would have had to have basically fireproof cavity trays for the horizontals, and solid fireproof columns on the verticals. What was ended up with was cavity barriers intended to expand against a solid surface e.g. a lintel, installed to expand against cladding that was simply hung on rails on the building.

And yes regarding the windows yes you are right the windows were moved in line with the rain screen, however there were no barriers around the windows to prevent fire whatsoever, just a bit of EPDM and some UPVC dabbed on. Meaning the fire was basically unstoppable once it melted the window reveals off.
PS I'm not a builder