Chapter 19: The BBA certificate for Reynobond 55 PE

The product

¶19.1 BBA certificate 08/4510 related to "Reynobond Architecture Wall Cladding Panels."¹⁰¹¹⁰¹ {BBA00000047}. They were described as

" . . . two 0.5 mm thick aluminium alloy sheets . . . bonded to either side of a core of low-density polyethylene (LDPE)."

¶The description continued as follows:

"The panels are available either plain-edged (riveted system) or flanged (cassette system), to suit architectural requirements (see Figure 1). A Duragloss or PVDF coating available in various colours protects the exposed face. A polyester primer protects the unexposed face. The products are also available in a fire-retardant grade (FR)."

¶19.2 Figure 1 showed what were said to be typical fixing systems and depicted the riveted and cassette versions. Otherwise, however, the certificate referred to the panels without any distinction between the two forms of fixing. Any reader of the certificate would therefore naturally understand that the performance of the panels, whether FR or PE, was not affected by the fixing system adopted.

¶19.3 As will become clear, at the request of Arconic the product was described in the form in which it left the factory. That blurred the distinction between the fire performance of the panels once fabricated into either riveted or cassette forms. It was wrong to say that the panels were "available" plain-edged or flanged, which suggested that Arconic supplied them in both forms. That increased the potential for confusion.

¶19.4 It is clear from the discussions that took place in 2007 that that had been Arconic's intention. What the BBA did not know, but Arconic did, was that the choice of fixing method made a significant difference to the fire performance of the product in use, as revealed by Tests 5A and 5B.

¶19.5 Arconic had chosen to withhold the results of Test 5B from the BBA and did not disclose that a separate test of the product in cassette form had taken place. Arconic was legally obliged under the terms of its contract with the BBA to provide it with the results of Test 5B. As a result of its decision not to do so, the BBA certificate was thoroughly misleading, because it failed to draw a distinction between the two fixing systems in relation to fire performance. Mr Schmidt was constrained to accept that the failure to make clear in the certificate that the B classification was obtained only in rivet form rendered the certificate wrong and such as to lead the reader into error.¹⁰²¹⁰² Schmidt {Day92/73:9}-{Day92/74:14}; {Day94/59:1}-{Day94/60:1}; {Day94/63:23}-{Day94/64:17}.

¶19.6 In both its evidence and its statements to the Inquiry, Arconic asserted that it was the responsibility of the designer in each case to ensure that Reynobond 55 PE was suitable for the use to which it was to be put and complied with any applicable regulations.¹⁰³¹⁰³ Schmidt {MET00053187/29} page 29, paragraph 90-93; Wehrle {MET00053190/11} page 11, paragraphs 40‑41; Froehlich {MET00053197/9} page 9, paragraph 33; Derrendinger {MET00053191/16} page 16, paragraph 41; {ARC00000770}. That is obviously correct up to a point but it assumes that the information required to make the decision is available to the designer. The primary purpose of a BBA certificate is to provide the designer with confirmation that the information it contains provides a suitable basis for making that decision. In the present case Arconic's argument ignores the fact that it withheld important information from the BBA and thereby caused the certificate to misrepresent the true position. Arconic knew that a BBA certificate was required to enable it to sell Reynobond 55 PE in this country precisely because designers considered it to contain reliable information about the characteristics of the product. It also knew that a designer reading the certificate would understand from the way it was worded that Reynobond 55 PE had been classed B-s2, d0 in European fire tests regardless of the fixing system adopted.

Behaviour in relation to fire

Section 6.1

¶19.7 The second sentence of section 6.1 of the certificate read as follows:

"A fire retardant sample of the product, with a gold-coloured Duragloss finish, when tested for reaction to fire, achieved a classification B-s1, d0 in accordance with EN 13501 : 2002."¹⁰⁴¹⁰⁴ {BBA00000047/5}.

¶19.8 The statement was supported by CSTB classification report No. RA06-0372 issued on 19 October 2006 for Reynobond FR tested in riveted form.¹⁰⁵¹⁰⁵ Report RA06-0372 {BBA00008042/155-162}. Claude Wehrle suggested that the BBA should specifically refer to this result in the certificate and the BBA agreed.¹⁰⁶¹⁰⁶ {MET00055859}; {BBA00008042/515}. However, like the classification report for Test 5A, the report stated in terms that the classification was applicable only to Reynobond FR in a riveted form. It is plain that it could never have been used to support a certificate for Reynobond PE, whether in riveted or cassette form.

Sections 6.2 and 6.3: Class 0

¶19.9 Section 6.2 of the certificate provided as follows:

"A fire retardant sample of the product, with a metallic grey PVDF finish, when tested in accordance with BS 476-6: 1989, achieved a fire propagation index (I) of 0 and, when tested in accordance with BS 476-7 : 1997, achieved a Class 1 surface spread of flame."¹⁰⁷¹⁰⁷ {BBA00000047/5}.

¶19.10 Warrington Fire's test reports on Reynobond FR panels supported that statement.¹⁰⁸¹⁰⁸ Numbered 132316 {BBA00008042/163-175}; numbered 132317 {BBA00008042/177-191}. Taken together, they established that the FR version of the panels had achieved Class 0. However, Arconic had never provided the BBA with any reports which showed that Reynobond PE had achieved or could achieve Class 0. During the assessment process, Arconic sent the BBA product literature which claimed that both Reynobond FR and Reynobond PE had achieved Class 0¹⁰⁹¹⁰⁹ Product Information brochure dated January 2005 {BBA00008042/39-81}; fire classifications {BBA00008042/43}; Discover New Perspectives marketing brochure dated November 2005 {BBA00008042/83-104}; fire classifications {BBA00008042/101}. but Arconic had no evidence to support the claim made about the PE product. Arconic's marketing brochure dated November 2005 headed 'Discover New Perspectives' also claimed that Reynobond PE had achieved Class 0 because of tests carried out by Warrington Fire Research in 1997,¹¹⁰¹¹⁰ These were tests 70707 and 70708 {BBA00008042/83-104}; fire classifications {BBA00008042/101}. but reports of those tests were never provided to the BBA and, in any event, they had been carried out on a different product, Reynobond 160 PE.

¶19.11 At section 6.3 the certificate provided:

"As a consequence of sections 6.1 and 6.2, the products may be regarded as having a Class 0 surface in relation to the Approved Document B of The Building Regulations 2000 (as amended) (England and Wales) …"¹¹¹¹¹¹ {BBA00000047/5}.

¶19.12 Similar wording was contained on the front of the certificate. Under the heading 'Key Factors Assessed' the certificate stated as follows:

"Behaviour in relation to fire – in relation to the Building Regulations for reaction to fire, the panels may be regarded as having a Class 0 surface in England and Wales… (see section 6)."¹¹²¹¹² {BBA00000047/1}.

¶19.13 This important part of the BBA certificate requires detailed consideration taking into account the evidence of the BBA, the statements of Mr Wehrle and the submissions of Arconic.

The BBA's evidence

¶19.14 John Albon said that the words "may be regarded as having a class 0 surface" were not intended to mean that the panels actually achieved that standard; they simply reflected the position in Diagram 40 of Approved Document B in which both Euroclass B and Class 0 materials were permitted for use on external walls of buildings over 18 metres in height. He also told us that by using those words the BBA was not intending to suggest that Euroclass B was equivalent to Class 0. It was known within the BBA that the concepts were different and could not be used interchangeably.¹¹³¹¹³ Albon {BBA00010723/18-19} pages 18-19, paragraphs 66-77; Albon {Day110/6:6-17}; {Day110/7:3-6}. Brian Haynes, who had been involved in testing and technical assessment at the BBA since 1973 and who by 2008 was the very senior head of a technical group with a broad portfolio, said something similar in his evidence.¹¹⁴¹¹⁴ Haynes {BBA00010784/6} page 6, paragraphs 26-28.

¶19.15 John Albon also told us, and the BBA argued,¹¹⁵¹¹⁵ Albon {Day110/7:20}-{Day110/8:6}; BBA closing statement {BBA00011297/17} paragraph 52. that the certificate had to be read in full, and that a reader who considered sections 6.1 and 6.2 carefully would understand that the BBA had no evidence that Reynobond PE panels had achieved Class 0 through BS 476-6 and 476-7 testing. However, he did accept that the wording was "poor".¹¹⁶¹¹⁶ Albon {Day110/7:8-11}. We think that the wording was not merely poor but misleading and (on Arconic's part) deliberately so for the reasons we have examined in earlier chapters.

¶19.16 In the section headed "Regulations" the certificate stated that in the opinion of the BBA, the panels, if used in accordance with the provisions of the certificate, would meet or contribute to meeting functional requirement B4(1) of the Building Regulations because they were judged to meet the Class 0 requirements. Someone reading that statement and the statement on the first page of the certificate that the panels might be regarded as having a Class 0 surface might well have been led to understand that the BBA itself had considered the relevant data and had come to the opinion that Reynobond PE did achieve Class 0.

¶19.17 The expression "may be regarded as Class 0" appears in BBA certificates relating to other cladding panels. John Albon told us that the BBA had tried to ensure some consistency of expression between certificates for products with similar properties,¹¹⁷¹¹⁷ Albon {Day109/111:13-22}. but it is clear that the expression was not used in the same way in all cases. In some cases the phrase "may be regarded as … Class 0" was used when the BBA had evidence of testing in accordance with BS 476 Parts 6 and 7 which satisfied the definition of Class 0 in Approved Document B.¹¹⁸¹¹⁸ For example, certificate 10/4746 for Alupanel XT cladding panels {BBA00000113}. In other cases the expression was used when test evidence satisfying the definition was not available for a panel of one particular colour but was available for the same panel in another colour.¹¹⁹¹¹⁹ For example, certificate 13/5022 for Stacbond PE and Stacbond FR Cladding Systems {BBA00000067}; Albon {BBA00010723/28} page 28, paragraph 111; Albon {Day110/13:4-15}; {Day110/l14:10-14}. In yet other cases the expression was used where there was evidence of classification as Euroclass B, apparently because of the equivalence implied by Diagram 40 of Approved Document B (although that was not stated in terms).¹²⁰¹²⁰ For example, certificate 06/4367 for Bauclad External Cladding Panels {CEP00050243/5}; certificate 08/4551 for Larson and Larson FR Wall Cladding Panels {BBA00000144}; certificate 12/4901 for Vitrabond Aluminium Composite Rainscreen Cladding Panels {BBA00000074}.

¶19.18 In our view the BBA ought to have made a greater effort to avoid giving the impression that Diagram 40 indicated an equivalence between national Class 0 and Euroclass B. We note that the certificate issued in August 2017, shortly after the Grenfell fire, did not use the expression.¹²¹¹²¹ {BBA00000046}.

Mr Wehrle's statements

¶19.19 Mr Wehrle said that he could not remember whether he had read through the BBA certificate but that he had not been aware of its contents in any detail until after the fire.¹²²¹²² Wehrle {MET00053190/16} page 16, paragraph 55. However, the evidence shows unequivocally that he was intimately involved in the negotiations with the BBA leading to its production and must have been aware of its contents in so far as they concerned matters such as fire performance.¹²³¹²³ Claude Wehrle reviewed drafts of the certificate in October 2007 {BBA00008042/535}; November 2007 {BBA00008042/515-517}; December 2007 {BBA00008042/465}.

¶19.20 However, despite his close involvement, Mr Wehrle did not comment at the time on the statement that Reynobond 55 PE might be regarded as having a Class 0 surface.¹²⁴¹²⁴ {BBA00000047/1} section 6.3. He said that he had no specific knowledge of the UK Building Regulations, including Diagram 40 in Approved Document B,¹²⁵¹²⁵ Wehrle {MET00053190/16} page 16, paragraph 55. although he was prepared to say that the BBA and others regarded Diagram 40 as allowing European Class B to be treated as equivalent to national Class 0.¹²⁶¹²⁶ Wehrle {MET00053190/16} page 16, paragraphs 55 and 56. However, there is no evidence that Mr Wehrle raised the question with the BBA.

¶19.21 Mr Wehrle also drew attention to the results of tests on another Arconic product, Reynobond 33 PE.¹²⁷¹²⁷ Wehrle {MET00053190/9} page 9, paragraph 34; Wehrle {MET00053190/14} page 14, paragraph 46. Arconic submitted that they were relevant because they supported the conclusion that Reynobond PE could achieve Class 0.¹²⁸¹²⁸ Written closing submissions on behalf of Arconic {ARC00000770/22} paragraph 103. However, Reynobond 33 PE had different physical properties which makes comparison inappropriate, as is borne out by the fact that no one drew those tests to the attention of the BBA. As with most such reports, the reports of the tests on Reynobond 33 contained an explicit warning that they could not be applied to any other product.¹²⁹¹²⁹ For example {ARC00000366/7}; {EXO00001960/7}.

¶19.22 Arconic also submitted that it could not be blamed for the BBA's decision in the absence of applicable test data to treat European Class B as equivalent to national Class 0 and to state that Reynobond 55 PE could be regarded as having a Class 0 surface.¹³⁰¹³⁰ Written closing submissions on behalf of Arconic {ARC00000770/16} paragraph 76. Like Mr Wehrle, Arconic suggested that Diagram 40 of ADB permitted one to extrapolate national Class 0 from the existence of European Class B,¹³¹¹³¹ Written closing submissions on behalf of Arconic {ARC00000770/6} paragraph 29(2). but that is not possible because the nature of the tests and the standards they apply are quite different.¹³²¹³² See Part 2, Chapter 5. The note to Diagram 40 states (admittedly less clearly than it might) that Class B and Class 0 are not equivalent. In any event, Arconic knew very well that there was no relevant test data under either classification system to support such a statement in relation to Reynobond 55 PE in cassette form.

¶19.23 In our view the expression "may be regarded as having a Class 0 surface" should not have been used. In the absence of test data satisfying the Class 0 requirements for the PE version of the panels the BBA ought not to have proposed it and Arconic should not have allowed it to be included in the certificate. It was not appropriate for the BBA to treat Diagram 40 in Approved Document B as permitting it to treat European Class B as equivalent to Class 0, but if that was the basis of the statement, it ought to have been clearly explained. Although we consider that any reasonably competent construction professional relying on the certificate ought to have read it in full and should not have relied on the statements about Class 0 in isolation,¹³³¹³³ Hyett {Day64/149:2}-{Day64/150:7}; {Day64/151:8-15}; {Day64/160:1-6}. the BBA and Arconic must both bear responsibility for the inclusion in the certificate of that misleading statement.

Section 6.3: the unexposed face of the product

¶19.24 The final sentence of Section 6.3 stated:

"The unexposed side of the products may also be regarded as having a class 0 surface".¹³⁴¹³⁴ {BBA00000047/5}.

¶19.25 That wording reflected a question which had arisen towards the latter stages of the assessment process and posed a significant problem for Arconic. The BBA considered that it needed reaction to fire test data for the back of the product as well as the face.¹³⁵¹³⁵ {BBA00010701/5}; {BBA00010701/1}. In the event, the BBA accepted test results from Arconic's Reynolux product as evidence that the coating on the back of Reynobond panels would perform at least as well as that on the front.¹³⁶¹³⁶ {MET00053158_P16/136-137}; {BBA00008042/525-527}; classification report RA07-0182 {BBA00008042/139-145}. Consequently the BBA agreed to state in the certificate that the unexposed face of Reynobond panels might "also be regarded as having a class 0 surface".¹³⁷¹³⁷ {BBA00000047/5}.

¶19.26 In coming to that conclusion, the BBA initially sought advice from Dr Sarah Colwell of BRE,¹³⁸¹³⁸ {BBA00008042/505-507}. but before it could be provided Mr Gregorian indicated that, following the receipt of further information from Arconic, the BBA no longer required its assistance.¹³⁹¹³⁹ {BRE00047592}; Colwell {Day233/67:12}-{Day233/68:3}. In circumstances where the BBA was dealing with claims about Reynobond's fire performance and recognised that its own expertise was limited, it should have taken advice from a body such as BRE which had expert knowledge of testing and fire performance. We consider that it was remiss of the BBA not to seek that advice when the Reynobond certificate was first drafted.

¶19.27 BS 476 Part 7 requires testing to be carried out on the complete product because the performance of the surface may be affected by the underlying material. It was wrong, therefore, for the BBA to accept results obtained from testing Reynolux, which is a solid aluminium panel, as representative of Reynobond, which is a composite panel.

Section 6.4: colour

¶19.28 Section 6.4 of the certificate drew attention to the fact that the fire performance of the products described in sections 6.1 and 6.2 might not be achieved by other colours.¹⁴⁰¹⁴⁰ {BBA00000047/5}. Hamo Gregorian added what had become a standard warning to the certificate on the advice of John Albon.¹⁴¹¹⁴¹ {BBA00010693}. It was the BBA's policy that reaction to fire testing was colour- specific, and so a BBA certificate would cover only the colours that had actually been tested.¹⁴²¹⁴² Albon {BBA00010723/27} page 27, paragraphs 104-109; Albon {Day110/22:15-25}; {Day110/26:2-13}. John Albon said that was because he had been advised that colour might make a difference to a product's fire performance.¹⁴³¹⁴³ Albon {Day110/25:11-22}; {Day110/26:2-13}; {BBA00010693}. However, there is no evidence that anyone at the BBA considered whether that might be so in the case of Reynobond 55. Accordingly, the BBA considered that the certificate applied only to Reynobond with a grey/green Duragloss 5000 coating, a gold-coloured Duragloss finish, and a metallic grey PVDF finish and no others.¹⁴⁴¹⁴⁴ BBA Closing Submissions {BBA00011297/25} paragraph 77; BBA Module 2 Closing Submissions {BBA00011296/9-10} paragraph 27-28. All other variants of the product would need a separate test or assessment. The BBA ought to have alerted Arconic to that narrow approach during the assessment process. However, the wording is sufficiently clear to have told Arconic that the certificate only covered, or might only cover, the colours and finishes specified, and that it was not able to support the sale of the product in any other colour or finish.

¶19.29 For its part, Arconic did not treat the BBA certificate as applicable only to the three colours and finishes to which it referred. In the case of Grenfell Tower, for example, Ms French on behalf of the company used it to support the sale of a wide range of colours,¹⁴⁵¹⁴⁵ Email from Deborah French to Mark Harris of Harley dated 23 April 2014 {RYD00003932}. including those ultimately chosen, namely, "Smoke Silver" and "Pure White", neither of which was covered by the certificate.¹⁴⁶¹⁴⁶ {ARC00000552}; {ARC00000553}. Arconic used the certificate to support the sale of all its Reynobond 55 panels in the UK without qualification as to colour. Ms French said that she had not been aware that only specific colours and finishes received the classifications stated in the BBA certificate, having never discussed the matter with Arconic.¹⁴⁷¹⁴⁷ French {MET00053162/4} page 4 paragraph 18; French {MET00053162/16} page 16, paragraphs 56 and 57. If that is true, then Arconic must be blamed for not ensuring that its sales representative was properly informed about the narrow scope of application of the BBA certificate. If, on the other hand, she was aware of those limitations when she provided the certificate to Harley on 23 April 2014 before the colour of the panels had been chosen, she would, or at any rate should, have warned Harley that the certificate did not cover other colours, including those that she knew were being considered, such as smoke silver and white.¹⁴⁸¹⁴⁸ {RYD00003932}. She did not do so.

Section 6.5: resistance to fire

¶19.30 Section 6.5 of the certificate warned that with regard to resistance to fire, the performance of a wall incorporating the product could be determined only by tests carried out by a suitably accredited laboratory.¹⁴⁹¹⁴⁹ {BBA00000047/5}. The wording, which can be found in other BBA certificates relating to cladding products,¹⁵⁰¹⁵⁰ For example, certificate 06/4367 for Bauclad External Cladding Panel {CEP00050243/5}; certificate 08/4551 for Larson and Larson FR Wall Cladding Panels {BBA00000144/5}; {BBA00000143/6}; certificate 10/4746 for Multipanel's Alupanel XT Cladding panels {BBA00000113/5}; certificate 13/5022 for Stacbond PE and Stacbond Cladding Systems {BBA00000067/9}; certificate 15/5245 for Ash & Lacy Building systems Alucobond façade cladding systems {BBA00000120/10}.Show full note also appears to have been standard.

¶19.31 Arconic submitted that the effect of section 6.5 was that readers of the certificate were given no assurance about the product's resistance to fire when incorporated into an external wall, the performance of which would have to be assessed by full-scale testing in accordance with BS 8414.¹⁵¹¹⁵¹ Module 6 closing statement {ARC00000794/16} paragraph 51; Overarching closing statement {ARC00000797/19} paragraph 68. By stating that the product had achieved European Class B-s2, d0 the BBA was merely identifying the standard to which Reynobond PE was capable of performing.¹⁵²¹⁵² {ARC00000797/27-28} paragraphs 99-104.

¶19.32 We were not impressed by that argument. Resistance to fire and reaction to fire are fundamentally different concepts and therefore testing resistance to fire (as addressed by testing to BS 476-20 to 476-24) necessarily involves methods different from those used to test reaction to fire.¹⁵³¹⁵³ Namely those listed in BS 476 Part 10, Guide to Principles, Selection, Role and Application of Fire Testing and their Outputs, being BS 476 Parts 20-24 {BSI00001757/5}. Reaction to fire tests are designed to measure the ease with which a material can be ignited, surface spread of flame, the rate of heat release and the production of smoke, whereas 'resistance to fire' tests are designed to measure the ability of an element of construction to contain fire, including its ability to protect a frame from collapse and to restrict the spread of smoke.¹⁵⁴¹⁵⁴ BS 476 Part 10, section 4 {BSI00001757/13-14}. BS 8414 is an entirely different kind of test, being designed to test the reaction of an entire wall system to fire.¹⁵⁵¹⁵⁵ BS 476 Part 10 separates full scale tests from "resistance to fire tests" see Foreword at (b) for fire resistance tests and "Miscellaneous" for full scale testing {BSI00001757/5}; Appendix B of ADB also distinguishes between resistance to fire and reaction to fire tests; Resistance to fire is assessed by tests such as BS-476-20 and EN 13501 parts 2 to 4) {CLG00000224/119}; Reaction to fire is assessed by those tests which for example combine to make up the EN 13501-1 classification {CLG00000224/121}.Show full note

¶19.33 Section 6.5 therefore did not qualify the statements about reaction to fire made elsewhere in the certificate, including in sections 6.1 to 6.3, and there is no support for Arconic's submission that all construction professionals should have known that a separate large-scale test was necessary before the product could be used in an external wall.

¶19.34 In any event, even if section 6.5 should be understood to mean that the fire resistance of a wall incorporating the product was outside the scope of the certificate, that was of no interest to a potential buyer of the panel who simply wanted to know whether Reynobond, as a product, complied with the guidance in Approved Document B in relation to buildings over 18 metres in height. The BBA certificate was a product certificate, and section 12.6 and Diagram 40 of Approved Document B are directed to products, not systems.