Grenfell Tower: how many high rise buildings are there in England with PE ACM cladding and phenolic insulation? (part 1)

On 5 September 2017, the Government published data for the number of high rise residential buildings in England (as of 31 August) with various types of ACM cladding, and with various types of insulation:

The number of buildings accounted for in this table is:

81 + 107 + 8 + 21 + 12 = 229.

The total number of buildings in England with ACM cladding (including those stripped post-Grenfell) is given in paragraph 5 (and also in paragraph 8):

Since 173 + 16 + 89 = 278, it is clear that 278 is the number of buildings as well as the number of samples.

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Grenfell Tower: is the core of ACM panels a ‘filler material’?

I have been examining three alternative rationales offered by the DCLG for their claim that the core of ACM panels is covered by paragraph 12.7 of Approved Document B2:

1. The ACM core is an insulation material or product;

2. The ACM core is a filler material;

3. All elements of the cladding system are covered, and so the ACM core is covered.

As I explained in part 1 of this series, the first of these rationales may be excluded immediately because ACM cladding has no insulation function. I showed in part 2 that common sense, logic and informed opinion rule out the third rationale, the application of 12.7 being clearly restricted to insulation and filler materials, with any further coverage limited to minor unspecified items.

In this post I demonstrate that that the core of cladding panels made of Aluminium Composite Material cannot properly be described as filler material. As I pointed out before, the DCLG itself finds this a doubtful proposition since in footnote 4 of its Explanatory Note on safety checks and testing of 30 June 2017:

with its ‘and/or’, the core is claimed to be either an insulation material/product, or an filler material, or both (but not neither!) So, according to the logic of this footnote at least, the ACM core could be just an insulation product and not a filler material at all.

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Grenfell Tower: was the cladding legal or not? (part 2)

In my last post, I pointed out the statutory requirement, contained in Article B4(1) of Schedule 1 of The Building Regulations 2010, that:

The external walls of the building shall adequately resist the spread of fire over the walls…

I then began to examine the guidance given by the government in Approved Document, Volume 2, at the corresponding part B4, as to how this statutory requirement can be met. Two alternative routes to compliance are given in Section 12.5:

In my last post also, I examined the provisions of paragraphs 12.6 to 12.9 and in particular of 12.6 and 12.7 which concern the fire properties of the materials used in construction. I explained that, for buildings over 18m high:

a) The requirement of 12.6 can be satisfied if the materials are UK Class 0. This classification can be achieved through satisfactory performance in two UK fire tests, BS 476 part 7 ‘Surface Spread of Flame’; and part 6 ‘Fire Propagation’. In both of these it is the surface of the board or panel that is subjected to assault by fire.

b) The requirements of 12.7 appear to apply to insulation products only.  The materials must either survive trial by a furnace at 750° C, or have a calorific value of less than 3 MJ/kg. I argue that no material with a substantial component of a polymer like the PIR of the Celotex boards, or the PE of the Reynobond panels, could possibly pass these tests.

In this post I describe the BS 8414 fire test, which is offered as an alternative route to compliance at paragraph 12.5. In following posts I plan to:

Continue reading Grenfell Tower: was the cladding legal or not? (part 2)

Grenfell Tower: was the cladding legal or not? (part 1)


Philip Hammond, the Chancellor, claimed on the Andrew Marr Show on 18 June 2017 that the cladding that was used on Grenfell tower is banned in the UK:

[17 JANUARY 2018. THIS PARAGRAPH REPLACES WHAT I WROTE IN JUNE 2017.

Was he right? If he was referring to the aluminium composite cladding panels, then he was not. Under the official Approved Document guidance, commonly known as the building regulations, the ACM panels used on Grenfell Tower possessed the requisite fire performance certification. This does not mean that they were safe. On the contrary, aluminium composite panels with a polyethylene core are highly combustible and should never be used on high buildings.

END OF NEW PARAGRAPH.]

Continue reading Grenfell Tower: was the cladding legal or not? (part 1)