The Road to Grenfell Hell was clad with Green Intentions

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grenfell-firesequence

Report written by commenter ‘stickywicket’ at Spiked online

Everyone has been shocked to the core by the images of the inferno that engulfed the Grenfell Tower, killing 79 people. Most were horrified by the suggestion in the Times that the cause of the fire might have been penny-pinching on the type of cladding used in the recent refurbishment of the building. It seems unbelievable that they didn’t spend an extra £5,000 for fire resistant cladding.

This is probably not the whole story. The revelation that a further 70+ tower blocks have failed fire safety tests tells us that there is an endemic problem. We don’t know the precise reasons for the fire yet, but we should certainly look at the influence of slavish devotion to green regulations.

The Grenfell refurbishment project apparently cost £8.6m, or >£70K per flat. The cost of the cladding, per the BBC Panorama documentary was £2.6m or >£20K per flat. This does not look like a project that was done on the cheap.

What pointers do we have that the drivers of the choice of materials might have been something other than small cost differences?

First, the regulations relating to cladding appear to be unclear, with some Government ministers suggesting the PE version on high-rise is illegal but others saying the rules are ambiguous. However, the manufacturer’s own guidelines say the FR version should be used on buildings over 10m and the even more fire resistant A2 version over 30m.

So, what might cause somebody to go against manufacturer guidelines? Well, the polyethylene (PE) variant of Reynobond cladding used is twice as thermally resistant as the fire retardant (FR) variant that would have cost £5,000 more to install. This is important in the context of the planning application and the regulations governing the refurbishment of buildings covered below.

Second, the insulation used was apparently Celotex RS5000, made from polyisocyanurate (PIR). Sky News has reported this material produces hydrogen cyanide when it burns and is, as we saw, highly combustible. This material is also rated A+ in the BRE Green guide. Interestingly, Celotex is 40% more insulating than the alternative incombustible Rockwool product. Celotex has thermal conductivity 0.021W/mK, compared to Rockwool Rainscreen Duo slabs of 0.035 W/mK.

It appears insulation performance was the main criterion used for material selection, not fire safety.

We also need to challenge the wisdom of spending more than £20,000 per flat on cladding in the first place. No matter how insulating the cladding was, this cannot be justified by the potential savings made on fuel bills to the occupants. A small portion of this money could have been used to install sprinklers for fire safety and install internal insulation. Energy efficient appliances were out of scope of the refurbishment project, but could have been fitted.

What do the planning application and the regulations tell us?

The Sustainability and Energy statement makes clear that “improving the insulation levels of the walls, roof and windows is the top priority of this refurbishment”. Indeed, they parade their green credentials by boasting that “the proposed insulation levels far exceed those required by Building Regulations”. In other words, they deliberately chose materials to be more insulating than required. There was no discussion of the fire safety impact of cladding and insulation or the potential need to install sprinklers. It appears concerns about insulation levels trumped any other consideration, even fire safety.

The report used by Kensington and Chelsea council to decide the planning application considered the application against many policies such as amenity, diversity of housing and climate change, but not apparently, any fire safety policy. The council admonishes itself for only achieving a ‘good’ rating against its climate change objective, but congratulates itself because “the proposed alterations which include the new windows, cladding materials and internal heating system will all provide a significant improvement to the sustainability of the building”.

The BREEAM report used to assess the sustainability credentials of the refurbishment has 43% of its evaluation criteria weighted towards Energy, a further 8% towards Materials and just 17% towards Health and Wellbeing, a small portion of which is devoted to fire safety.

They achieved a measly single credit for saying they would install fire and carbon monoxide detectors in each flat. But they got a total of 10 credits for improving the energy efficiency and reducing primary energy demand. They got a further 19 credits for using “materials [that] will have a green guide rating of at least A+” and 8 more for using highly insulating materials.
In summary, 1 credit for fire safety and a total of 37 credits for green environmental measures.

The primary focus of the BREEAM framework is energy efficiency, with precious little focus on fire safety. Is it any wonder fire safety was apparently disregarded? It would be interesting to see what the BREEAM scores would have been had they used the FR/A2 versions of the cladding and Rockwool insulation.

This evidence points to environmental concerns trumping other considerations when choosing the refurbishment materials. It certainly challenges the narrative that the choice of cladding material was driven by cost cutting.

This surely leads to several questions for the Public Inquiry:

1) What was the primary purpose for choosing Reynobond PE over Reynobond FR or A2? Was it cost or was it insulation performance.

2) What was the reason for choosing combustible PIR insulation instead of incombustible Rockwool? Was it insulation properties or cost?

3) PIR insulation is common place in the building industry. Why are these products allowed to be placed in any buildings, when they are clearly combustible and emit poisonous fumes when burnt?

4) Why does ‘sustainability’ rank higher than fire safety in building regulations?

5) Should the building regulations be changed to place greater emphasis on fire safety over and above sustainability considerations?

Of course, it is too early to allocate blame, but surely the Public Inquiry should tell us whether we have sacrificed 79 people on the altar of Gaia.

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Reynobond specification: http://ift.tt/2ufAgTO

Reynobond fire solutions (p2, top left): http://ift.tt/2ufAgTO
Rockwool Rainscreen Duo specification: http://ift.tt/2ti7J2Q