Chapter 56: The choice of insulation

Chapter 56: The choice of insulation

¶56.1 The purpose of adding insulation to a building is to keep it warmer in winter and cooler in summer. Laura Johnson, Head of RBKC's Housing Department, accepted that at the end of 2011 there was no evidence that the thermal efficiency of Grenfell Tower was sufficiently poor to justify the investment in cladding; she thought, at least at the outset, that the primary rationale for cladding it was to improve its appearance.^13651365 Johnson {Day128/32:15}-{Day128/35:1}. Bruce Sounes thought that the modernisation of the heating system, the replacement of the windows and the addition of insulation were all integral to the refurbishment of the building, but he had not been involved in RBKC's original decision.^13661366 Sounes {Day12/190:9-12}.

¶56.2 Two insulating products were ultimately used in the construction of the external wall of Grenfell Tower, Celotex RS5000 ("RS5000") and Kingspan Kooltherm K15 ("K15").^13671367 See Grenfell Tower Inquiry Phase 1 Report, Volume I, Chapter 6 for a description of the construction of the external facade. RS5000 was a polyisocyanurate ("PIR") rigid foam board insulation. K15 was a phenolic ("PUR") rigid foam board insulation. Both were combustible, with a short time to ignition.^13681368 Grenfell Tower Phase 1 Report, Volume I, Chapter 6, paragraph 6.20. Neither RS5000 nor K15 met the limited combustibility guidance in paragraph 12.7 and table A7 of Approved Document B; and neither of them had been tested in accordance with BS 8414 in combination with the other materials intended for use on the tower. It follows that the system had not been shown to meet the criteria set out in BR 135. No alternative way of establishing compliance with the Building Regulations, e.g. by way of a desktop report or a holistic fire-engineered solution, had been followed. The use of those products was therefore contrary to official and industry^13691369 For example, CWCT's Technical Note 73, Fire Performance of curtain walls and rainscreens, dated March 2011 at {CWCT0000019/6}. guidance and, as the Chairman found in his Phase 1 report, the external wall of the building as a whole, including the insulation, was combustible and did not adequately resist the spread of fire over the walls. The use of those materials was therefore a clear breach of functional requirement B4(1) of the Building Regulations. In this chapter we seek to explain how the insulation came to be chosen for use on the tower.

The initial selection of Celotex FR5000: 2012–2014

¶56.3 Celotex FR5000 was the insulation product specified in the contract between the TMO and Rydon. It was specified by Studio E in the NBS Specification in November 2013,^13701370 {SEA00000169/73} final version of 30 January 2014: thermal insulation was specified at item 776. which formed part of the Employer's Requirements. However, the origins of that decision can be traced back to early in the previous year.

¶56.4 On 24 May 2012, there had been a design team meeting at which insulation was discussed, but only in very general terms.^13711371 Minutes at {ART00000037}. In attendance at this meeting were various representatives of the TMO, Bill Watts of Max Fordham, and Bruce Sounes of Studio E. The minutes were circulated to James Lee of Exova. Some consideration was given to installing insulation internally, rather than on the outside of the building,^13721372 {ART00000037/2}. but that option had been quickly rejected because it would have caused too much disruption to residents.^13731373 McQuatt {Day42/35:17-21}. At that meeting Max Fordham was instructed to assist the design team in establishing environmental design criteria, including U-values, ventilation openings and other matters, in order to advance the design of the cladding.^13741374 {ART00000037/2}. U-value is a measure of the rate of heat transfer through a material or structure, measured in watts per square metre kelvin (W/m2K). The lower the U-value, the better the material or structure's thermal efficiency; that is, the more it prevents heat loss in winter and heat gain in summer. Lambda value is a measurement of thermal conductivity of a material, measured in watts per metre kelvin (W/mK). The lower the lambda value of a material, the less is needed to achieve the desired U-value. Following the meeting, Bruce Sounes understood that Max Fordham was to provide the environmental design criteria, including the U-values.^13751375 Sounes {Day12/192:21-24}; {Day12/193:4-6}; Sounes {SEA00014273/39} page 39, paragraph 81.

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¶56.5 On 18 June 2012, Matt Smith of Max Fordham sent an email to Bruce Sounes asking what U-value Studio E was seeking to achieve.^13761376 {SEA00004737}. Andrew McQuatt of Max Fordham understood that Mr Smith had written that email to prompt Studio E to suggest its own U-value, assuming that Studio E as architect was designing the whole system and that Max Fordham did not have the power to specify any of the elements of the cladding. The email was intended to stimulate a dialogue with Studio E about the overall design, including the U-value.^13771377 McQuatt {Day42/44:10}-{Day42/46:3}. In response, Mr Sounes instructed a colleague to send Max Fordham drawings of the likely build-up of the cladding system.^13781378 {SEA00004737}.

¶56.6 At a design team meeting on 25 June 2012,^13791379 {ART00000096}. Attended by the TMO, Studio E and Max Fordham, among others. Bill Watts of Max Fordham suggested a target U-value of 0.15 W/m2K for the walls of the tower.^13801380 {ART00000096/2}. Another U-value was suggested for the windows. McQuatt {Day42/38:3-11}. That was ambitious. It was to become the target U-value for walls of new buildings in the Approved Documents published in 2013,^13811381 {INQ00015203/39}. but in 2012 the Approved Documents required a U-value of 0.30 W/m2K only for walls of existing buildings with external insulation,^13821382 See Approved Document L 1B at {INQ00011283/20}, Table 3 and also Approved Document L 2B {INQ00015204/25} at Table 5. as was recorded in the minutes of the meeting.^13831383 {ART00000096/2}. Even greater latitude was provided in the Approved Documents, which stated that where a U-value of 0.30 W/m2K could not be achieved, the external wall should reach the best standard that was technically and functionally possible.^13841384 See Document L1B at {INQ00011283/20}, Section 5.9 and Document L2B at {INQ00015204/24} section 5.10.

¶56.7 Max Fordham's suggestion that the designers seek to achieve a U-value of 0.15 W/m2K was therefore twice the efficiency required by the statutory guidance for existing buildings. The purpose of doing so was, in summary, to ensure that the building would continue to perform well by future standards.^13851385 McQuatt {Day42/39:10-16}; {Day42/41:9-19}. See also {MAX00000412/6}. at table 2.1. In addition, Max Fordham considered that, in principle, overcladding an existing high-rise building did not differ in principle from constructing a new one.^13861386 McQuatt {Day42/38:12-21}; {Day42/39:6-16}. Another consideration was that the London Plan recommended reducing energy use by improving the fabric of the building first^13871387 McQuatt {Day42/39:17-25}. and there was also a widespread recognition in the industry of the importance of improving the fabric of buildings. Accordingly, it was environmental considerations, including energy efficiency, that lay at the heart of the U-value that was chosen.^13881388 McQuatt {Day42/40:1-9}.

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¶56.8 When he came to work on the project, Andrew McQuatt checked that the U-values suggested by Max Fordham were consistent with Approved Document L. He understood that if the target was not achievable, it was permissible to depart from it to a U-value that was technically and functionally feasible.^13891389 McQuatt {Day42/8:4-8}; {Day42/10:15-20}; {INQ00011283/20}; Bruce Sounes was not aware that Approved Document L provided that flexibility. Sounes {Day20/10:18}-{Day20/11:3}. Max Fordham did not think that the U-value it had suggested was unduly ambitious.^13901390 McQuatt {Day42/40:12-21}. Bruce Sounes also shared that view,^13911391 Sounes {Day20/33:13-15}. and realised that Max Fordham was seeking to match the statutory guidance relating to new buildings.^13921392 Sounes {Day20/9:21}-{Day20/10:17}; {Day20/18:4-9}. Neither Max Fordham nor Studio E checked the proposed U-value against the fire safety guidance in Approved Document B to see whether a higher U-value would have to be accepted in order to comply with the guidance on insulation contained in paragraph 12.7.^13931393 McQuatt {Day42/47:21}-{Day41/48:7}.

¶56.9 Following Max Fordham's suggestion, Bruce Sounes carried out some research into insulation products. On 5 July 2012, he asked Rockwool^13941394 Rockwool is a company manufacturing a range of mineral or stone wool insulation products for use in external cladding systems, among other applications. According to the CWCT in Technical Guidance Note 73 dated March 2011, mineral wool was the only insulation product which would satisfy the definition of "limited combustibility" in Approved Document B (see Chapter 49). to advise which mineral wool insulation product it would be appropriate to use within an external cladding system and what thickness would be required to achieve a U-value of 0.15 W/m2K.^13951395 {SEA00004967}. Mr Sounes sent an email to Andrew McQuatt and Matt Smith telling them that he had sent enquiries about insulation to both Rockwool and Kingspan,^13961396 {SEA00004973}. attaching a spreadsheet with some calculations. At that point, neither Studio E nor Max Fordham had given any consideration to using a Celotex product, or indeed any polymeric material.

¶56.10 The spreadsheet contained an analysis of the thickness of mineral wool that would be required to achieve a U-value of 0.15 W/m2K.^13971397 {SEA00001334}. Mr Sounes had carried out that analysis himself using various thicknesses of one of Rockwool's products, "Rainscreen Duo Slab". For each thickness of the product, he derived the corresponding U-value by extrapolation from the information in the datasheet. He calculated that 325mm of Duo Slab would achieve a U-value of only 0.20 W/m2K.^13981398 Sounes {Day20/15:17-22}. He concluded that to achieve a U-value of 0.15 W/m2K about 450mm of Duo Slab would be required.^13991399 {SEA00004973}; {SEA00004974}. It was on that basis that he said in his email to Max Fordham that the target U-value of 0.15 W/m2K looked to him "a bit aspirational" and he questioned whether it would be feasible to use Rockwool, given the thicknesses apparently required to achieve it.^14001400 {SEA00004973}. Mr Sounes did not ask Max Fordham or anyone else to check his calculations^14011401 Sounes {Day20/25:4-9} and McQuatt {Day42/65:9-14}. and he did not check Approved Document L to see what U-value the guidance required.^14021402 Sounes {Day20/9:11-20}.

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¶56.11 In the light of his calculations Mr Sounes might have been expected to consider whether he should abandon the proposed U-value 0.15 W/m2K in favour of a higher value that might be easier to achieve, but he does not appear to have done so. He did not think that "aspirational" meant irresponsible; it just meant trying to do the best you can.^14031403 Sounes {Day20/17:24}-{Day20/18:1}. He said that Max Fordham had prided itself on being an aspirational engineer and that Studio E had followed it. He had seen no reason to abandon a U-value of 0.15 W/m2K and thought that it had been in the project's interest to try to achieve it.^14041404 Sounes {Day20/27:9-23}. The target U-value was never rejected by Studio E as being unachievable. Sounes {Day20/4:20-21}; {Day20/16:24-25}.

¶56.12 In his email of 5 July 2012, Bruce Sounes had referred to Max Fordham's having "asked for" a target U-value of 0.15 W/m2K. Mr Sounes said in evidence that in the past Studio E had looked to Max Fordham to propose U-values and he was doing the same in connection with the Grenfell Tower project.^14051405 Sounes {Day20/3:23}-{Day20/4:1}; {Day20/17:20-22}. It was part of Max Fordham's role, as set out in its fee proposal, to help the architect to comply with the energy efficiency requirements in Part L of the Building Regulations.^14061406 {MAX00000075}.

¶56.13 In our view, although Max Fordham did first suggest a target U-value of 0.15 W/m2K for the external walls in its capacity as the building services engineer,^14071407 McQuatt {Day42/44:4-9}. it was Studio E's responsibility, as lead consultant and lead designer, to assess the feasibility of that U-value in the context of its initial design of the cladding system. Max Fordham did not "ask for" that U-value or specify it in such a way as to oblige the design team, including Studio E, to accept it without question. A reasonably competent lead consultant and lead designer would not have considered itself limited in any way in its selection of materials or the design of the cladding system by suggestions made by the M & E consultant. Mr Sounes accepted as much,^14081408 Sounes {Day20/17:15-18}. and rightly so. The services to be provided by Studio E included co-ordinating the design of all constructional elements, including work by consultants, specialists or suppliers, and determining materials, elements and components, standards of workmanship, type of construction and performance in use.^14091409 Appendix B: Schedule of Services {SEA00009824/7}. It was Studio E's responsibility as architect and lead designer to decide what U-value was feasible and appropriate.

¶56.14 Matt Smith replied to Bruce Sounes on 5 July 2012, probably after having discussed the matter with Andrew McQuatt.^14101410 McQuatt {Day42/66:3-8}; {SEA00004978}. He had done a quick calculation using the lambda value for the Rockwool product and the thicknesses proposed by Mr Sounes. It was his view that the thicknesses of Rockwool calculated by Mr Sounes were too great and he questioned whether Mr Sounes had taken thermal bridging^14111411 A thermal bridge is an area or component of an object which has higher thermal conductivity than the surrounding materials, creating a path of least resistance for the transfer of heat. into account.^14121412 {SEA00004978}. Matt Smith's calculation did not include any thermal bridging considerations, because Max Fordham did not have any more specific details of the design of the cladding to enable him to do so.^14131413 McQuatt {Day42/68:22}-{Day42/69:6}. It was Andrew McQuatt's own view that Mr Sounes' analysis may have been based on rather pessimistic assumptions.^14141414 McQuatt {Day42/69:15}-{Day42/70:7}.

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¶56.15 In the same email Matt Smith referred to a "glass fibre slab" product.^14151415 {SEA00004978}. It is not clear whether that was a mistake,^14161416 McQuatt {Day42/67:4-6}. but in any event, Andrew McQuatt said that both the mineral wool and glass fibre products were flexible and had similar lambda values, so the calculation he provided was reasonable despite any potential confusion between the two products.^14171417 McQuatt {Day42/67:11-23}.

¶56.16 Andrew McQuatt thought at this point that the U-value might need to be changed, given that Studio E considered that the necessary thickness of mineral wool could not be accommodated. However, he knew that the Kingspan rigid insulation board would be a thinner product and thought that it would be appropriate to wait to see what Kingspan said in response to Bruce Sounes' email of 5 July 2012 before commenting further.^14181418 McQuatt {Day42/49:15}-{Day42/50:9}.

¶56.17 On 6 July 2012 Bruce Sounes sent an email to Matt Smith to tell him that Kingspan had recommended 200mm of its phenolic foam product to achieve the required U-value.^14191419 {SEA00004986}. The calculations by Kingspan can be found at {MAX00000104}. He also attached to his email a product datasheet for a mineral wool insulation manufactured by Superglass Insulation Ltd called "Cladding Mat 37",^14201420 {SEA00001337}. Cladding Mat 37 is a form of mineral wool insulation, marketed as an A1 non-combustible product. but that was rejected because it was thought that too great a thickness would be required.^14211421 McQuatt {Day42/80:10-20}. Bruce Sounes did not consider the fire performance of that product. Sounes {Day20/36:2-6}.

¶56.18 On 24 July 2012, Ian Pritchard of Rockwool responded to Bruce Sounes' email of 5 July 2012. He said that they would normally recommend the use of Rainscreen Duo Slab for the type of construction that Mr Sounes had in mind, but that due to the low U-value required the thickness needed would be exceptionally high, probably beyond the point of sensible building practice.^14221422 {SEA00005276/2}. Bruce Sounes forwarded Rockwool's email to Matt Smith and Andrew McQuatt, drawing attention to his concerns about buildability and appearance if mineral wool were used.^14231423 {SEA00005276}. Neil Crawford could not recall any discussion about the use of a mineral wool product in the external wall facade but had understood that the thickness of the product required would have been impractical. He thought he got that understanding from Bruce Sounes. Crawford {Day10/67:12-21}. He did not ask Max Fordham to obtain from Rockwool a formal calculation of the thickness of material required, so apart from Matt Smith's "quick calculation" no attempt was made at any stage to determine precisely what thickness of mineral wool would be required to achieve a U-value of 0.15 W/m2K.

¶56.19 Andrew McQuatt understood the email from Mr Sounes to mean that he had decided that the maximum thickness for the insulation should be 200mm.^14241424 McQuatt {Day42/60:17-20}. He thought that Mr Sounes' calculations formed part of a bigger picture; he did not question it because he assumed that Studio E had chosen it as the best thickness for a wide range of reasons.^14251425 McQuatt {Day42/61:5-9}.

¶56.20 There was never any serious discussion about increasing the U-value to something greater than 0.15 W/m2K,^14261426 McQuatt {Day42/43:6}-{Day42/44:3}. and Studio E did not raise the possibility of doing so with Max Fordham.^14271427 Sounes {Day20/33:17-25}. According to Andrew McQuatt, the design team remained confident that a reasonable technical solution to the problem could be found, so there was never any resistance to adopting the ambitious U-value.^14281428 McQuatt {Day42/43:19-23}.

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¶56.21 Bruce Sounes sent another email to Andrew McQuatt on 15 August 2012 asking for his help in calculating the thickness of insulation required to achieve the target U-value.^14291429 {SEA00005818}. He attached to his email a further calculation of the thickness of mineral wool insulation required.^14301430 {MAX00000214}. The exchange occurred just before a report was to be made to the Planning Department in which the proposed U-value would be disclosed, so it was important to make sure the external wall could be built to produce that U-value. Mr Sounes was concerned whether the proposed U-value could be achieved over all the different elements of the wall.^14311431 McQuatt {Day42/53:7-22}.

¶56.22 On either 15 or 16 August 2012, there was a telephone conversation between Andrew McQuatt and Bruce Sounes during which Mr McQuatt attempted to answer Mr Sounes' concern. He undertook to do some calculations based on the different areas of the building in order to determine whether the target U-value could be achieved on average across the building as a whole and to establish the thickness of insulation required to achieve the target U-value overall.^14321432 McQuatt {Day42/81:21}-{Day42/82:12}.

¶56.23 On 16 August 2012 Andrew McQuatt sent Mr Sounes his calculations^14331433 {SEA00005840}. and attached the product datasheet for Celotex FR5000.^14341434 {SEA00005841}. Issue 2, January 2012. In order to do his U-value calculation, Mr McQuatt had needed to use the lambda value of an insulation product. In his mind there was little difference between the rigid board insulation products marketed by Kingspan and those sold by Celotex, so he went to the Celotex website and looked at a datasheet for a solid insulation board, FR5000. He obtained the lambda value from the datasheet and sent it to Mr Sounes so that he could see the source of the information he had used.^14351435 McQuatt {Day42/82:13}-{Day42/82:17}. He thought that Celotex FR5000 was the only type of product that would provide the required thermal performance at a thickness that could realistically be accommodated.^14361436 {SEA00005840}. When Andrew McQuatt said in this email of 16 August 2012 that Celotex FR5000 was "the only type of product that will give us the required performance", he had in mind the lambda value of the product and that, at least in his mind, FR5000 was interchangeable with a rigid insulation board marketed by Kingspan. McQuatt {Day42/85:3-9}.

¶56.24 Celotex FR5000 was a polyisocyanurate (PIR) product. The datasheet^14371437 {SEA00005841} Issue 2, January 2012. made no reference to its being suitable for use as part of a cladding system nor did it state that it was suitable for use on buildings with a storey above 18 metres in height. It did not say that FR5000 was a product of limited combustibility, but it did say that it had Class 0 fire performance throughout the entire product in accordance with BS 476.

¶56.25 Andrew McQuatt did not give any thought to the fire performance of Celotex FR5000 before he sent his email to Bruce Sounes on 16 August 2012.^14381438 McQuatt {Day42/86:20}-{Day42/87:18}. Mr Sounes had suggested both the Rockwool product and the Kingspan product and Mr McQuatt thought that the use of Kingspan had already been established.^14391439 McQuatt {Day42/85:3-9}. Since Studio E had proposed a Kingspan product as an option from the outset, he had thought there was nothing wrong with using it or, by extension, Celotex FR5000.^14401440 McQuatt {Day42/61:18-22}. He accepted that he would have been just as likely to put forward the Kingspan product if he had obtained the lambda value of one of their foam boards instead of a Celotex product.^14411441 McQuatt {Day42/86:2-7}.

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¶56.26 At the time, Andrew McQuatt was not aware of the guidance given in Approved Document B about insulation materials and their combustibility, nor could he recall with any certainty having heard the expression Class 0.^14421442 McQuatt {Day42/18:8}-{Day42/19:12}. He was not aware of industry guidance on the construction of external walls and insulation materials and had never had cause to look at the guidance published by the Centre for Window and Cladding Technology (CWCT).^14431443 McQuatt {Day42/21:20}-{Day42/22:4}. He was aware that there were different types of insulation and he knew that Kingspan produced a solid board rather than a mineral wool product, but that was really the extent of his knowledge.^14441444 McQuatt {Day42/51:9-16}. No one had suggested to him that phenolic or PIR foam insulation boards were not appropriate for use in the external walls of buildings above 18 metres in height.^14451445 McQuatt {Day42/91:25}-{Day42/92:4}.

¶56.27 The suggestion made by Andrew McQuatt in his email of 16 August 2012 that a PIR insulation product might be used did not give Bruce Sounes any cause for concern. He told us that PIR and phenolic insulation boards had become all but standard by that time^14461446 Sounes {Day20/39:2-3}. and that PIR products were widely used in the industry, which reassured him about their suitability.^14471447 Sounes {Day20/40:8-15}. Bruce Sounes said that every project that he had worked on involved some form of foam board in the facade, but he confirmed that those other projects had involved low-rise buildings. Sounes {Day20/39:6-14}. He said he thought he had been aware that PIR insulation had been used on high-rise buildings. Sounes {Day20/50:11-15}. Mr Sounes thought that Celotex FR5000 was suitable for use as part of the cladding system partly because it had been used in the past by Max Fordham in what he had understood to be similar circumstances, but he took no steps to find out whether Max Fordham had ever used FR5000 in the past in the external wall of a building over 18 metres in height. He could not recall having read the datasheet for Celotex FR5000 when he was working on the project, nor did he recall noting at the time that it was rated Class 0,^14481448 Sounes {Day12/178:4-7}; {Day12/183:14-17}. but if he had been aware of that it would have served only to increase his confidence in its use, because he understood that if a product was rated Class 0 it was, as he put it, "not hazardous".^14491449 Sounes {Day12/183:6-13}. Mr McQuatt did not realise that Studio E had understood his email of 16 August 2012 as a tacit endorsement of the safety of FR5000 for use on the building,^14501450 McQuatt {Day42/84:19-23}; {Day12/181:12-23}. but there is no reason why he should have done so, given that his expertise did not extend to fire safety and he had not been consulted about that.

¶56.28 Mr McQuatt wrote a Sustainability and Energy Statement in respect of the project dated 17 August 2012,^14511451 {MAX00000412/6}. which made it clear that the recommended U-value far exceeded that required by the Building Regulations.^14521452 {MAX00000412/6} at Table 2.1. At Tables 2.2 and 2.3 of the report, Celotex FR5000 was identified as the insulation for the spandrels and columns.^14531453 {MAX00000412/6}. When he received it, Bruce Sounes did not pause to consider whether mineral wool could be used to produce a U-value which, although higher, still complied with the regulations.

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¶56.29 On 10 October 2012, Max Fordham issued its RIBA Stage C report.^14541454 {MAX00000636}. Andrew McQuatt drafted most of it, with a contribution from Matt Smith.^14551455 McQuatt {Day42/92:5-12}. The information contained in the Sustainability and Energy Statement was repeated on page 12 of the report.^14561456 {MAX00000636/12}. Mr McQuatt explained that FR5000 had been referred to in the Stage C report solely because it delivered the U-value required at the thickness sought.^14571457 McQuatt {Day42/95:10-17}. He said that detailed information had been included in the report so that readers could see how the thermal conductivity value had been achieved for the insulation. If for any reason FR5000 had not been used, the technical details were available to enable a substitution to be made.^14581458 McQuatt {Day41/92:18}-{Day41/93:11}. He did not see it as his role to influence the design team's decision about the materials to be selected.^14591459 McQuatt {Day42/93:13}-{Day42/94:1}. Andrew McQuatt could not recall whether a final decision had been taken to use FR5000. Max Fordham's Stage C report makes no reference to fire safety because its practice was to advise on questions of fire safety only to the extent that they affected the work that the building services engineer was specifying.^14601460 McQuatt {Day42/94:16-25}. We therefore infer that, as Max Fordham was not responsible for choosing the insulation, it did not regard itself as responsible for giving advice in the Stage C report about its use, whether in relation to fire safety or otherwise.

¶56.30 Studio E issued its own RIBA Stage C report on 31 October 2012.^14611461 {ART00008396}; {MAX00000445}. It incorporated Max Fordham's Stage C report and referred to Celotex FR5000 as the chosen insulation.^14621462 {MAX00000445/82}. Before issuing the report, Bruce Sounes did not ask Exova or Max Fordham or any other specialists to advise on the suitability of using Celotex FR5000 in the cladding system or whether its use would comply with the Building Regulations.

¶56.31 In January 2013, Adrian Jess^14631463 Sounes {SEA00014273/59} page 59, paragraph 124. sent a draft of Studio E's Stage D report to Leadbitter, which at that stage was expected to become the principal contractor for the project. It showed EPS (expanded polystyrene) insulation at the lower levels of the tower behind rainscreen panels.^14641464 {MET00081283/11} under Item P10. On 21 January 2013 Juan Medina, Framework Design manager for Leadbitter, sent Mr Jess an email asking whether Studio E had checked with building control whether EPS insulation could be used on a tower of that kind. Mr Medina understood that EPS was a combustible material and was not allowed as part of a rainscreen cladding system. He suggested that phenolic insulation should be used instead.^14651465 {MET00081282}. The email was copied to Studio E and is therefore likely to have been seen by those at Studio E who were working on the project, including Bruce Sounes. Although the discussion concerned the lower levels of the tower, it shows that Studio E was on notice from January 2013 that building control might not allow combustible insulation to be used in a rainscreen cladding system. That warning by Leadbitter ought to have prompted Studio E to pay close attention to the fire performance of the insulation materials that it had proposed for the project. However, from the documents available to the Inquiry, it does not appear that the warning resulted in any discussion of that kind within Studio E.

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¶56.32 Studio E issued its final Stage D report on 20 August 2013,^14661466 {MAX00000757}. which proposed the use of Celotex FR5000.^14671467 {MAX00000757/29}. Between issue of its Stage C and Stage D reports there were no communications between Studio E, Max Fordham, Exova, or any other specialist about the safety of using FR5000 product or how it reacted to fire.^14681468 Bruce Sounes could not recall whether he had asked building control about the acceptability of using a PIR product in a high-rise building. Sounes {Day20/51:1-18}.

¶56.33 On 25 October 2013, Tomas Rek commented in an internal email to Bruce Sounes that Max Fordham's U-values were "OTT", i.e. excessive.^14691469 {SEA00014346/2}; {SEA00014346/2}; Rek {Day12/137:2-17}. Tomas Rek thought he had had a discussion with Mr Sounes about it, but he could not recall what Mr Sounes had said.^14701470 Rek {Day12/138:24}-{Day12/140:7}. Bruce Sounes did not remember any discussion of that kind.^14711471 Sounes {Day20/33:3-10}. In any event, no further attempts were taken by Mr Rek to address his concerns.^14721472 Andrew McQuatt said in his evidence that no one had ever referred to the target U-value as "over the top" to him. McQuatt {Day42/57:22}-{Day42/58:16}. Mr Sounes thus missed the opportunity properly to understand Mr Rek's concerns about the U-values and to check with Max Fordham whether they needed to be quite so ambitious.

The Hays Galleria meeting: insulation

¶56.34 As we have found when describing the discussions about the choice of cladding material, on 27 September 2013 Bruce Sounes and Tomas Rek met Ray Bailey and Mark Harris of Harley at a coffee shop in Hays Galleria in south London.^14731473 Near London Bridge station. The purpose of the meeting was to discuss the lay concept design drawings for the refurbishment. Ray Bailey {HAR00010184/20} page 20, paragraph 77. As well as discussing the rainscreen, they also discussed the insulation for Grenfell Tower. What was said on that matter was the subject of differing recollections and the evidence about it requires detailed consideration.

¶56.35 Ray Bailey said that Studio E had given Harley calculations relating to U-values in advance of the meeting, from which he had seen that it intended to specify a PIR insulation product.^14741474 Ray Bailey {Day32/149:21-25}; {Day32/150:1-22}. In his witness statement, Bruce Sounes said that at the time of the meeting he had had a lingering uncertainty about the fire safety of PIR because he was dealing with a high-rise building and had not worked on one before. He thought he had asked Ray Bailey about the acceptability of using a rigid foam insulation on such a building, but did not remember having received a clear response.^14751475 Sounes {SEA00014273/114} page 114, paragraph 271. Repeated in his oral evidence Sounes {Day20/49:9-12}.

¶56.36 Bruce Sounes said that insulation had been discussed in general as part of the assembly of the facade^14761476 Sounes {Day20/47:3-9}. and that he might not have mentioned that he had Celotex in mind.^14771477 Sounes {Day20/46:24-25}; {Day20/47:1-5}. Mr Sounes said that his doubt about the acceptability of a rigid foam insulation product was an afterthought and that he had not had a serious concern.^14781478 Sounes {Day20/50:3-4}. Indeed, he said that he had not raised the question with Exova because it was not a genuine concern.^14791479 Sounes {Day20/50:17-22}.

¶56.37 Bruce Sounes recalled that during the meeting he had looked at photographs of Ferrier Point under construction, in which the mineral wool insulation used in the external wall was visible. It was that, as he recalled it, which prompted him to question the use of rigid foam board insulation.^14801480 Sounes {Day20/47:10-15}; {Day20/50:22}-{Day20/51:1}. The photographs at {SEA00003497} and {SEA00003516} are similar to those shown by Ray Bailey to Bruce Sounes at the Hays Galleria meeting, although Bruce Sounes could not be sure that he was shown those particular photographs. Sounes {Day20/51:12-25}. Ray Bailey said that before the meeting Mark Harris had sent Studio E some photographs of buildings that Harley had previously worked on^14811481 Ray Bailey {Day32/152:2-6}. and agreed that it was possible that those or some similar photographs had been discussed at the meeting.^14821482 Ray Bailey {Day32/152:10-18}. However, he could not recall discussing whether the insulation proposed for use on Grenfell Tower was mineral wool or rigid foam, in contrast to that used on Ferrier Point.^14831483 Ray Bailey {Day32/152:23}-{Day32/153:1}. Mark Harris said that he did not recall having shown photographs at the meeting, but that it would not be unusual to do so and might have happened.^14841484 Harris {Day34/56:8-21}.

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¶56.38 There is nothing in the documents to indicate that Bruce Sounes questioned the use of PIR insulation during the meeting.^14851485 {ART00001487}. Mr Sounes emailed various parties at Artelia, TMO and Max Fordham with a summary of the matters discussed at the Hays Galleria meeting. Mr Sounes' remarks that Harley "pointed to Ferrier Point as being very similar to Grenfell, although it is triple glazed and super insulated". Aside from this there is no reference to any discussion regarding the insulation. Tomas Rek did not recall Bruce Sounes raising the matter with him^14861486 Rek {Day12/135:14-16}. and he could not recall whether the suitability of PIR or rigid foam insulation had been discussed during the meeting.^14871487 Rek {SEA00014278/10} page 10, paragraph 29. Mr Rek could not recall any discussions about fire safety or performance of the insulation during the meeting.^14881488 Rek {Day12/133:7-18}.

¶56.39 Neither Ray Bailey nor Mark Harris had any recollection of Bruce Sounes asking about the acceptability of using rigid foam products on high-rise buildings.^14891489 Ray Bailey {Day32/149:14-17}; {Day32/151:23}-{Day32/152:6}.,^14901490 Harris {Day34/54:14-17}; {Day34/55:5-7}; {Day34/56:4-7}. Ray Bailey said that the question would have struck him as odd, because PIR was a product Harley had not used on a high-rise building at that stage.^14911491 Ray Bailey {Day32/149:19}-{Day32/150:22}; Ray Bailey {Day32/153:7-16}. It was Ray Bailey's impression at the time that there was no flexibility in the choice of insulation and that FR5000 had already been selected.^14921492 Ray Bailey {Day32/153:7-16}. Ray Bailey said that no one at Studio E or Harley had asked him about the suitability of the Celotex insulation or whether its use complied with the Building Regulations.^14931493 Ray Bailey {Day32/153:2-6}.

¶56.40 There is little doubt that photographs of Ferrier Point were shown and discussed at the meeting and it is likely that there was some comment about the use of a mineral wool insulation on that building. We think it unlikely, however, that Bruce Sounes asked whether rigid foam insulation was acceptable for use on Grenfell Tower. If it had been sufficiently important in his mind for him to have done so, it is likely that Ray Bailey would have made some response and that he would have remembered what it was. It is also likely that there would have been some reference to it in the contemporaneous documents. Asking about the safety of PIR would not have been consistent with Mr Sounes' understanding of its suitability in general or with his lack of curiosity about the fire safety of the products he proposed to use in the cladding system.

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Celotex FR5000 in the NBS Specification

¶56.41 Studio E produced three versions of the NBS Specification for the project dated 21 November 2013,^14941494 {SEA00000152}. 29 November 2013^14951495 {SEA00000153}. This was the version issued to tenderers. and 30 January 2014 respectively.^14961496 {SEA00000169}.

¶56.42 Studio E started work on the Employer's Requirements, including the proposed NBS Specification, early in 2013.^14971497 Sounes {Day7/150:18-25}. The NBS Specification was prepared largely by Tomas Rek at Bruce Sounes' direction and subject to his oversight, Adrian Jess having already done some initial work^14981498 Rek {SEA00014278/5} page 5; Rek {Day12/10:22}-{Day12/11:1}. Work had already begun on the NBS specification. Rek {Day12/12:7-13}. before he was made redundant in March 2013. By September 2013 the project had been developed to Stage D (the Stage D report was dated 20 August 2013). Tomas Rek was told to use Studio E's Stage D report and drawings to draw up the NBS specification and Mr Sounes gave him additional information as required.^14991499 Rek {Day12/10:22}-{Day12/11:1}; {Day12/15:1-9}.

¶56.43 In the case of the insulation to be applied to the external concrete walls Studio E made a proprietary specification; in other words, in all three versions of the NBS Specification Celotex FR5000 was specified as the product to be used.^15001500 See the "thermal insulation" section within section H92 at item 776. In the final version {SEA00000169/73}; Sounes {Day7/162:1-9}. However, that was subject to the qualification that the product could be substituted by a similar or equal alternative.^15011501 {SEA00000169/64}. The contract preliminaries provided that if a contractor wished to suggest an alternative product it was required to provide reasons for that substitution to the client.^15021502 Clause 2.2.2 {RYD00094235/64}. The NBS Specification was not unusually prescriptive and was no more detailed or prescriptive than specifications commonly written by Studio E.^15031503 Sounes {Day7/168:10-19}.

¶56.44 Before specifying the product, neither Tomas Rek nor Bruce Sounes had investigated whether the use of Celotex FR5000 on a building above 18 metres in height complied with either the Building Regulations or the guidance contained in Approved Document B. Mr Sounes had not asked Max Fordham that question and he did not revisit it when overseeing the writing of the NBS Specification.^15041504 Sounes {Day20/42:6-11}. Similarly, Mr Sounes did not seek advice from Exova about the suitability of FR5000 for use in the refurbishment before the NBS Specification was prepared.^15051505 Sounes {Day20/42:12}-{Day20/43:6}. Bruce Sounes said that he understood Adrian Jess and Tomas Rek to have had independent discussions with Exova, but he was not aware of their content. He said that he could not recall himself raising the use and suitability of FR5000 with CEP. Sounes {Day20/43:16-19}.

¶56.45 Bruce Sounes said that Studio E would not usually seek to satisfy itself that all materials and products complied with the regulatory requirements before submitting a full plans application to building control.^15061506 Sounes {SEA00014273/121} page 121. In his view it would be a waste of time to do so, because the contractor under a design and build contract might subsequently propose a change or building control might take a different view of their suitability.^15071507 Sounes {Day20/64:21-24}; {Day20/65:5-8}. He said it was not common practice to do a full assessment of the suitability of products at RIBA Stages D or E.^15081508 Sounes {Day20/65:1-3}. Mr Sounes did tell us, however, that before the submission of the full plans application to building control in August 2014, he had been reasonably confident that the materials specified in it complied with the Building Regulations and Approved Document B, because all the products had (as he believed) been used before in similar circumstances, either by Studio E itself or others.^15091509 Sounes {Day20/67:5}-{Day20/68:11}. However, the steps he had taken to investigate precisely what had been used and in what circumstances were negligible.

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¶56.46 Following the submission of the full plans application to building control there was no subsequent occasion on which Studio E would check whether the materials complied with the Building Regulations. Mr Sounes said that, because this was a design and build project, once the contract had been awarded the architect was, as he put it, "sidelined" so that Studio E was not policing what other people were doing.^15101510 Sounes {Day20/71:3-14}. That, however, ignores the role played by Studio E after it had been engaged by Rydon. For the reasons we have explained below and in Chapter 63, it should have given further consideration to whether the insulation complied with the Building Regulations, but failed to do so.

¶56.47 At the time he prepared the NBS Specification, Tomas Rek did not know that the fire performance of each of the components of the cladding would need to be considered.^15111511 Rek {Day12/24:16-21}. He had a general awareness of functional requirements B3 and B4, having come across them on a previous project^15121512 Rek {Day12/16:7-23}. which had required one part of the facade to be Class 0.^15131513 Rek {Day12/17:1-4}. In that context he had also had to consider diagram 40.^15141514 Rek {Day12/25:24}-{Day12/26:11}. It was Mr Rek's understanding that Class 0 was concerned with the external spread of flame and that if a material had that classification it would not encourage the spread of flame.^15151515 Rek {Day12/18:9-15}. However, it became clear during his oral evidence that his knowledge of Approved Document B was very limited. He was not familiar with the various different routes to compliance described in paragraph 12.5 of Approved Document B,^15161516 Rek {Day12/20:15-20}. or the definition of what would constitute a material of limited combustibility,^15171517 Rek {Day12/42:6-19}. or the guidance in paragraph 12.7.^15181518 Rek {Day12/26:20}-{Day12/27:21}. He could not recall having checked the requirements for external walls contained in Approved Document B when drawing up the specification.^15191519 Rek {Day12/44:10-19}; Rek {Day12/45:16-20}. Nor could he recall talking to anyone at Studio E about which route to compliance with the Building Regulations it had taken in respect of the refurbishment of the external wall.^15201520 Rek {Day12/22:17-23}. Mr Rek did not himself give any consideration to that question. {Day12/22:25} – {Day12/23:2}. He did not know whether the proposed cladding system had been tested to BS 8414 and met the criteria in BR 135 criteria or if a fire engineer's report had been obtained. {Day12/27:23}-{Day12/28:9}.

¶56.48 The insulation to be used as part of the cladding was specified in clause H92/776 of the NBS Specification. Within section H92/776 of the RIBA software in use at the time for compiling an NBS Specification, the details were left blank for completion. Upon selecting clause H92/776, two tabs would appear: tab G, "Guidance" and tab H, "Manufacturers". Under tab H there is a list of manufacturers available for selection derived from the NBS Plus database.^15211521 {INQ00011333}. At the time of drawing up the specification for the thermal insulation in November 2013, four manufacturers appeared in tab H: Kingspan with its K15 Kooltherm product, Knauf, Rockwool and Siderise.^15221522 {INQ00011366}. No Celotex product was listed under tab H. Accordingly, in order to specify Celotex FR5000 it was necessary for the writer to enter the product manually. When Celotex FR5000 was manually entered under clause H92/776 a message appeared informing the compiler that that product had been authorised for an alternative clause, clause P10.^15231523 {INQ00011342}. Clause P10 was the section covering insulation fitted between rafters.^15241524 {INQ00011341}. It would therefore require a conscious decision to enter FR5000 under that section of the NBS Specification despite the warning.

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¶56.49 Tomas Rek could not recall having seen that message but could recall having seen a similar notice when trying to alter clauses which were pre-filled.^15251525 Rek {Day12/122:9-15}; {Day12/123:1-12}. He could not, however, recall being informed that the insulation that was being specified in clause H92/776 was identified by the software as suitable for a different application.^15261526 Rek {Day12/123:17-21}.

¶56.50 When a person drawing up the specification for clause H92/776 clicked on the drop- down box next to the entry for "Manufacturer", the software would prompt him to select "mineral wool to BS EN 13162" as the only option and then provide a list of four manufacturers.^15271527 {INQ00011351}. If the writer did not wish to select a mineral wool product, that entry would have to be manually overridden.^15281528 Rek {Day12/127:3-8}. That is what happened here. Mineral wool was manually overridden and Celotex FR5000 was manually typed in at clause H92/776 of the NBS Specification.

¶56.51 Although he was responsible for drawing up most of the NBS Specification, Tomas Rek could not recall whether he himself had entered FR5000 or whether it had already been in the specification when he came to the project. He said that if he had entered that product he had derived that requirement from Studio E's Stage D report and probably Max Fordham's Stage C report.^15291529 Rek {Day12/118:10}-{Day12/119:12}; {Day12/125:1-14}. Mr Rek thought he would have spoken to Bruce Sounes about the specification of products.^15301530 Rek {Day12/130:20-25}. He said that he had assumed that the design of the cladding and the choice of materials had been considered by Studio E before he had started work on the project.^15311531 Rek {Day12/44:22}-{Day24/45:1}. Mr Rek did not recall any discussion with Bruce Sounes about the reasons for choosing FR5000 for use in the cladding system,^15321532 Rek {Day12/135:17-20}. nor could he recall considering whether FR5000 was combustible or non-combustible.^15331533 Rek {Day12/124:10-13}. He did not consult any of the product information about FR5000^15341534 Rek {Day12/131:14-25}. and did not discuss its fire performance with anyone else at Studio E.^15351535 Rek {Day12/134:11-13}. He did not seek any assistance or advice about whether he should override the software and manually enter FR5000.

¶56.52 Clauses H92/220 and H92/310 of the NBS Specification stipulated that the contractor was to comply with CWCT Standard for Systemised Building Envelopes, including Part 6, which related to fire performance.^15361536 {SEA00000169/68-69}. It is not clear whether Mr Rek put that requirement into the NBS Specification, but he remembered having thought that it should be included.^15371537 Rek {SEA00014278/33} page 33; Rek {Day12/34:18}-{Day12/35:2}. Although he knew that CWCT had published guidance, he had not read it^15381538 Rek {Day12/19:14-18}. and was not familiar with it.^15391539 Rek {Day12/34:14-17}; {Day12/39:1-16}. Nor was he familiar with the guidance issued by the Building Control Alliance (BCA).^15401540 Rek {Day12/19:20-23}.

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¶56.53 Tomas Rek would normally have expected tenderers to check that FR5000 complied with the CWCT performance requirements, but he did not do so himself.^15411541 Rek {Day12/127:10}-{Day12/128:3}; {Day12/128:4-24}. He said that if the material specified did not comply with that standard there would be a conflict which would have to be resolved.^15421542 Rek {Day12/129:2-3}.

¶56.54 The NBS Specification was not sent to either Exova or Max Fordham for them to comment on the inclusion of FR5000 (or indeed at all). Bruce Sounes did not look to Exova to provide detailed checking of the specification because he did not consider that to be the focus of its work, which was to produce the fire safety strategy.^15431543 Sounes {Day20/51:2-10}.

¶56.55 Following the inclusion of FR5000 in the NBS Specification, no further consideration was given to it during the procurement process or before the award of the contract to Rydon in March 2014.

¶The "launch" of RS5000 and Harley's initial discussions with Celotex: April to August 2014

¶56.56 Jonathan Roome was a manager at Celotex whose work mainly related to sales.^15441544 Roome {Day69/7:6-10}. He joined Celotex in March 2014. On 28 April 2014, his colleague Jonathan Roper sent him information about the FR5000 range of products and the BS 8414 testing regime.^15451545 {CEL00001200}; {CEL00001201}; {CEL00001203}. Mr Roome then familiarised himself with Approved Document B and knew that there were particular requirements relating to high-rise buildings.^15461546 Roome {Day69/32:15-20}. He knew that if one wanted to follow the guidance in Approved Document B, a PIR product could be used in the external wall of a high-rise building only if it was of limited combustibility or formed part of a system that had undergone a BS 8414 test and met the criteria in BR 135.^15471547 Roome {Day69/39:16-22}. He was also aware that FR5000 and other PIR products were neither materials of limited combustibility nor had been tested in a system that had undergone a BS 8414 test and met the criteria in BR 135. They could therefore not be used in the external walls of buildings above 18 metres in height consistently with the guidance contained in paragraphs 12.5-12.7 of Approved Document B.^15481548 Roome {Day69/19:22-24}; {Day69/20:2-10}; {Day69/39:12-15}; {Day69/30:11-15}. He knew that there was a distinction between Class 0 materials and materials of limited combustibility^15491549 Roome {Day69/36:10-15}. and was aware of the tests which a material needed to pass to obtain that classification.^15501550 Roome {Day69/25:19-23}.

¶56.57 In about April 2014 Mr Roome became aware that Celotex was seeking to develop an insulation product that could be marketed for use in buildings above 18 metres in height.^15511551 Roome {Day69/43:16-25}. He understood that the new product (which was formally launched as RS5000 in August 2014) was an equivalent product to Kingspan's K15, if not better.^15521552 Roome {Day69/163:14-22}. As we have already explained, RS5000 was simply FR5000 re-marketed with the supposed benefit of having successfully met the BR 135 criteria in a particular wall construction, but that fact was not known to Mr Roome, who had been led to believe by his seniors in the marketing department that it was a brand new product.

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¶56.58 On 10 June 2014 Mr Roome telephoned Ben Bailey of Harley to discuss another of Harley's projects, Merit House.^15531553 {CEL00009874}. Ben Bailey wanted to know if Celotex had an alternative to Kingspan K15 that might be used at Merit House. Mr Roome said that because Merit House was a building above 18 metres in height Celotex did not have a suitable product, but that he would contact Harley once Celotex's 18 metre fire test was in hand. That was a reference to a BS 8414 test using RS5000 which had been carried out 2 May 2014, the results of which were awaited together with the BR 135 classification report.

¶56.59 By June 2014 Jonathan Roome was aware that Harley had been awarded two new overcladding projects in London^15541554 Roome {Day69/160:14-21}. and between early June and the end of August 2014 Celotex saw Harley as a potential customer for RS5000.^15551555 Roome {Day69/174:8-13}.

¶56.60 As a result of his conversation with Mr Roome on 10 June 2014, Ben Bailey knew that Celotex did not then have any insulation products available that could be used on buildings above 18 metres in height.^15561556 And he knew that there were restrictions on insulation products being used on those buildings. Ben Bailey {Day39/55:15-25}; {Day39/56:1}. When he began work on the Grenfell Tower project he read through those parts of the NBS Specification which he considered relevant to Harley's work.^15571557 Ben Bailey {Day39/64:21-25}; {Day39/65:1-19}. It did not occur to him, however, to question the specification of FR5000, despite knowing that Celotex did not have a suitable product.^15581558 Ben Bailey {Day39/66:16-21}; {Day39/68:13-25}; {Day39/69:3-7}.

¶56.61 Jonathan Roome met Ben Bailey on site at Merit House on 18 July 2014 when he was told that Grenfell Tower was one of Harley's prospective projects.^15591559 {CEL00009875}. Ben Bailey was under the impression by that time that Celotex was due to bring out an insulation product suitable for use above 18 metres^15601560 Ben Bailey {Day39/61:4-20}. which would be a competitor to Kingspan's K15.^15611561 Ben Bailey {Day39/58:5-13}. Mr Roome promised to be in touch when the result of the test involving RS5000 was available. According to Ben Bailey, Jonathan Roome was very keen to stay in contact about the RS5000 product and to secure two overcladding projects, including the Grenfell Tower refurbishment.^15621562 {CEL00009875}; Ben Bailey {Day39/61:21-25}.

¶56.62 RS5000 was launched at a meeting on 5 August 2014 attended by a number of Celotex's employees, including Jonathan Roome.^15631563 Roome {CEL00010031/7} page 7, paragraph 29; {CEL00009709}; {CEL00008668}. It was made clear to him that the reason RS5000 had (supposedly) been created and brought to market was for use on buildings above 18 metres in height and the communications strategy was to emphasise that it could be used on buildings of that kind.^15641564 Roome {Day69/48:19-24}; Roome {Day69/69:19-23}. Mr Roome was provided with documents to pass on to potential customers,^15651565 Rome {CEL00010031/2} page 2. including a product data sheet for RS5000, a document entitled

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¶Rainscreen Cladding Compliance Guide and a document entitled Rainscreen Cladding Specification Guide.^15661566 {CEL00007961}; {CEL00000012/2}; {CEL00000013}; Roome {Day69/100:23-25}; {Day69/101:1-5}. The purpose of the documents was to present RS5000 as a new product suitable for the insulation of buildings above 18 metres in height, which is what Mr Roome thought it was.^15671567 Roome {CEL00010031/2} page 2, paragraph 6; {CEL00001237}.

¶56.63 Having seen the documents, Mr Roome knew that RS5000 could not satisfy the requirements of paragraph 12.7 and table A7 of Approved Document B because it was not a material of limited combustibility.^15681568 Roome {Day69/95:16-20}. The construction of the system that had been tested on 2 May 2014, apparently successfully, was discussed at the presentation on 5 August 2014, from which he understood that the classification of RS5000 under BR 135 applied only to the system as tested and not to its individual components.^15691569 Roome {Day69/52:1-9}. He also knew that RS5000 could be used only in cladding systems that were identical to the system tested.^15701570 Roome {Day69/98:8-13}.

¶56.64 On 6 August 2014, Mr Roome sent Ben Sharman of Harley an email about RS5000 to which he attached a product comparison document, the rainscreen cladding compliance guide, the product datasheet and a rainscreen cladding datasheet.^15711571 {CEL00001237}; {CEL00001238}; {CEL00001239}; {CEL00001240}; {CEL00001241}. In his covering email he said,

"I have the pleasure of informing you as of yesterday we have now launched the first PIR Board To Successfully Meet The Performance Criteria in BR 135 For Insulated Rainscreen Cladding Systems, Therefore Acceptable For Use In Buildings Above 18m in Height".

¶56.65 Jonathan Roome had taken that wording from a document prepared by Celotex's marketing team. It did not include the qualification that RS5000 was suitable for use on high-rise buildings only as part of a cladding system that was identical to the system that had been tested^15721572 Roome {Day69/167:20}-{Day69/168:10}. and therefore was, as he accepted, potentially misleading.^15731573 Roome {Day69/168:7-10}.

¶56.66 In his email of 6 August 2014 Mr Roome asked to visit Harley's offices to present the new product.^15741574 {CEL00001237}. Neither he nor any of Harley's witnesses could recall the precise date or circumstances in which that had occurred, but various conversations took place between Mr Roome, Daniel Anketell-Jones, and Ben Bailey about RS5000.^15751575 Roome {Day69/190:15-25}; Ray Bailey {HAR00010184/29} page 29; Anketell-Jones {HAR00010149/6} page 6; Ben Bailey {Day39/63:14-17}; {Day39/64:4-7}; {Day39/75:15-25}; {Day39/76:1-11}.

¶56.67 Ben Bailey told us that Jonathan Roome regularly visited Harley's offices and that he might have introduced RS5000 to a number of Harley's employees at different times.^15761576 Ben Bailey {Day39/63:14-17}; {Day39/64:4-7}; {Day39/75:15-25}; {Day39/76:1-11}; {Day39/76:20-21}; {Day39/77:1-4}. Mr Anketell-Jones, who was at that time the design manager at Harley, recalled a representative of Celotex visiting Harley's offices on a number of occasions to discuss RS5000, and more generally that Jonathan Roome visited the office every couple of weeks and perhaps 30 times a year.^15771577 Anketell-Jones {HAR00010149/6} page 6; Anketell-Jones {Day36/77:6-9}. Jonathan Roome could not recall the number of visits to Harley's offices, but would visit the offices to obtain information on Harley's projects and organise his sales pipeline.^15781578 Roome {Day69/174:15-23}. As at August 2014, Celotex was working on two projects for Harley (neither of them high-rise buildings) and Jonathan Roome hoped that Celotex could secure more work from Harley.^15791579 Roome {Day69/175:2-16}.

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Harley's understanding of the fire performance of Celotex RS5000

¶56.68 Ray Bailey said that because RS5000 was a new product, Harley had wanted to be sure that it was safe^15801580 Ray Bailey {Day33/68:23-25}. and suitable for the Grenfell Tower project.^15811581 Ray Bailey {Day33/69:6-8}. He said that Celotex had been keen to emphasise that it complied with BS 8414 and was suitable for buildings over 18 metres in height.^15821582 Ray Bailey {Day32/16:21-24}.

¶56.69 Daniel Anketell-Jones recalled that Jonathan Roome had made a sales pitch for RS5000, the essence of which had been that it was the first product suitable for use on buildings over 18 metres in height,^15831583 Anketell-Jones {HAR00010149/6} page 6; Anketell-Jones {Day36/79:2-13}; {Day36/88:6-9}. as claimed in Celotex's communications strategy.^15841584 Roome {Day69/177:14-17}. He also recalled seeing the marketing brochures provided to him by Mr Roome and recognised the pink branding on the documents.^15851585 Anketell-Jones {HAR00010149/6} page 6. He did not, however, read those brochures; he simply passed them on to others.^15861586 Anketell-Jones {Day36/93:15-25}; {Day36/94:1-3}; {Day36/97:24-25}; {Day36/98:1-6}.

¶56.70 Ray Bailey said it had been Mr Anketell-Jones' responsibility to examine the components of the cladding shown in the NBS Specification to check that they complied with the relevant statutory requirements^15871587 Ray Bailey {Day32/51:4-13}. and thought that he had done so.^15881588 Ray Bailey {Day32/51:4-13}; {Day32/17:21}-{Day32/18:1}. Mr Bailey himself just assumed that they were compliant and did not check for himself.^15891589 Ray Bailey {HAR00010184/8} page 8, paragraph 31. He was aware of the guidance in Approved Document B that the insulation should be of limited combustibility and thought that Celotex's products were materials of limited combustibility because they were rated Class 0.^15901590 Ray Bailey {Day33/22:12-15}. He thought that a Class 0 material was safe to use on any part of a building above 18 metres.^15911591 Ray Bailey {Day33/6:18-25}. He was aware of the distinction between Class 0 and limited combustibility, and of the fact that additional tests were required to establish the latter,^15921592 Ray Bailey {Day33/9:2-9}. but he appears to have regarded them largely as interchangeable concepts.^15931593 Ray Bailey {Day33/10:6-8}. For example, he thought that Class 0 related to the outside of a product but that if it were described as Class 0 "throughout", that meant the product as a whole was of limited combustibility.^15941594 Ray Bailey {Day33/12:12-15}; {Day33/13:3-10}; {Day33/14:7-12}; {Day33/15:8-11}; {Day33/11:7-9}. He was wrong about that, as he accepted,^15951595 Ray Bailey {Day33/19:2}. and was therefore wrong in thinking that Celotex products were materials of limited combustibility.^15961596 Ray Bailey {Day33/21:3-7}; {Day33/23:2-24}.

¶56.71 Mr Anketell-Jones had no recollection of the insulation products that were used on Grenfell Tower. He did not recall that the NBS Specification had required Celotex FR5000^15971597 Anketell-Jones {Day36/70:21-24}. and said that he had become aware of the products used only from media reports following the fire.^15981598 Anketell-Jones {Day36/69:1-9}; {Day36/78:3-20}. He said that he had not known what "PIR" meant but considered it to be a better performing kind of insulation.^15991599 Anketell-Jones {Day36/89:4-18}. He thought that Class 0 meant that a material could not catch fire.^16001600 Anketell-Jones {Day36/92:7-14}. He did not investigate the materials provided in the NBS Specification to see whether they complied with the Building Regulations^16011601 Anketell-Jones {Day36/63:19-23}. because he did not regard that as part of his job. He said that it had been his practice to send technical information about materials to a project's design team and building control for approval. He had not done so in the case of the Grenfell Tower project because he did not consider himself to be the main designer;^16021602 Anketell-Jones {Day36/65:9-21}. that role was being performed by Studio E and building control.^16031603 Anketell-Jones {Day36/71:10-22}. Mr Anketell-Jones was not aware that anyone at Harley had considered the suitability of FR5000 for the refurbishment.^16041604 Anketell-Jones {Day36/71:14-17}.

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¶56.72 Daniel Anketell-Jones was not aware that RS5000 had been tested as part of a particular cladding system or that the cladding system proposed for Grenfell Tower differed from that which had been tested.^16051605 Anketell-Jones {Day36/96:4-25}; {Day36/97:1}; {Day36/104:8-11}. He knew nothing about the BS 8414 test or BR 135 classification and did not form any view about whether testing under those regimes meant that RS5000 could be used on Grenfell Tower.^16061606 Anketell-Jones {Day36/95:8-25}; {Day36/96:1-3}. As a result of what he had been told by Jonathan Roome and what he had read on the front of the Celotex literature,^16071607 Anketell-Jones {Day36/91:6-13}; {CEL00007961}. he thought that RS5000 could be used on any building above 18 metres in height, regardless of the other components of the external wall.^16081608 Anketell-Jones {Day36/90:10-13}. It is likely that Mr Roome pointed out the key aspects of Celotex's marketing literature to Mr Anketell-Jones,^16091609 Anketell-Jones {Day36/93:15-25}; {Day36/94:1-3}; {Day36/97:24-25}; {Day36/98:1-6}. although he could not recall talking through the RS5000 specification or compliance guides with anyone at Harley or explaining the test regime.^16101610 Roome {Day69/174:7-10}; {Day69/177:24-25}; {Day69/178:1-7}. Certainly no steps were taken by Mr Anketell- Jones to satisfy himself independently that RS5000 was suitable for use in buildings above 18 metres in height,^16111611 Anketell-Jones {Day36/79:14-25}; {Day36/80:1-5}. a claim which he took at face value.^16121612 Anketell-Jones {Day36/80:6-10}. He did not trouble to read the RS5000 sales literature and did not see the qualifications and warnings.^16131613 Anketell-Jones {Day 36/98:20}-{Day36/99:12}.

¶56.73 Ben Bailey also remembered the pink branded Celotex marketing literature, but was unsure whether he had read it,^16141614 Ben Bailey {Day39/78:20-24}. although he did remember that the marketing literature had said that RS5000 was Class 0 throughout.^16151615 Ben Bailey {Day39/79:2-5}. He said he had seen the product comparison sheet or the rainscreen cladding specification guide^16161616 {CEL00000007}; {CEL00000013} which formed part of the package of documents sent by Jonathan Roome to Daniel Anketell-Jones on 27 August 2014 {CEL00011960}; Ben Bailey {Day39/82:10-17}; {Day39/82:1-24}. and was unsure whether he had seen the rainscreen cladding compliance guide.^16171617 {CEL00000012}; Ben Bailey {Day39/81:18-25}; {Day39/83:6-14}. He said that he had not been aware that RS5000 would comply with Approved Document B in relation to buildings above 18 metres in height only if it was used as part of a cladding system that corresponded exactly with the one tested.^16181618 Ben Bailey {Day39/83:21-25}; {Day39/84:1}.

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¶56.74 Jonathan Roome did not discuss with anyone at Harley the differences between FR5000 and RS5000, despite the fact that FR5000 rather than RS5000 had been included in the NBS Specification which Mr Anketell-Jones had seen.^16191619 Roome {Day69/199:18-25}; {Day69/200:1-2}. Similarly, Mr Roome did not point out to anyone at Harley that RS5000 could be used only on buildings over 18 metres in height if the cladding system corresponded exactly to the one that had been tested.^16201620 Roome {Day69/178:19-25}; {Day69/200:3-12}; Anketell-Jones {Day 36/97:9-20}; {Day36/98:7-22}; {Day36/99:13-24}. Harley never asked Jonathan Roome to explain the precise differences between the system as tested and the proposed cladding system for Grenfell Tower. Roome {Day69/126:22-25}; {Day69/127:1-4}. Jonathan Roome did not qualify the suitability of RS5000 on buildings above 18 metres with any caveats.Show full note Neither Harley nor Celotex made a comparison between the cladding system tested and the cladding system proposed for Grenfell Tower.^16211621 Roome {Day69/201:6-11}; Anketell-Jones {Day36/81:17-19}; {Day36/96:24}-{Day69/97:2}.

¶56.75 Jonathan Roome accepted that the limited relevance of the BS 8414 test involving RS5000 was important and that it was important that Harley understood it. He accepted, however, that he had not specifically drawn Mr Anketell-Jones's attention to it. His excuse was that Mr Anketell-Jones was a specialist and that he had thought he understood it from the information contained in the marketing literature Harley had been given.^16221622 Roome {Day69/179:4-20}; {Day69/200:13-16}; {Day69/201:3-5}; {Day69/200:13-20}; Anketell-Jones {Day36/79:4-8}. Mr Roome did not insist on seeing the composition of the cladding system proposed for Grenfell Tower to enable him to advise Harley whether RS5000 was suitable,^16231623 Roome {Day69/127:5-8}. nor did he point out to anyone at Harley that FR5000 might not be safe to use on buildings over 18 metres in height.^16241624 Anketell-Jones {Day36/79:11-13}. Harley did not ask Mr Roome for information about the BS 8414 test beyond that which was contained in the marketing literature and Mr Roome did not volunteer any.^16251625 Roome {Day69/192:7-18}.

Handover to Neil Crawford: August 2014

¶56.76 Neil Crawford began work on the Grenfell Tower project in about July 2014.^16261626 Crawford {Day9/116:19-21}. In about August 2014, Bruce Sounes had a handover meeting with him.^16271627 Crawford {Day9/49:23}-{Day9/50:3}. Neil Crawford was working on the project between July and August 2014, but his involvement had been minimal: Crawford {Day9/50:4-9}. It is likely that Mr Sounes gave Mr Crawford a general description of the NBS Specification during the handover.^16281628 Crawford {Day9/136:21}-{Day9/137:3}. When Mr Crawford started work on the project, therefore, FR5000 was the insulation product included in the NBS Specification. Neil Crawford could not recall whether Mr Sounes had told him that FR5000 had been specified as the insulation to be used within the external facade, but it is likely that he had read Max Fordham's Stage C report and had seen the reference to it there.^16291629 Crawford {Day9/135:15}-{Day9/136:5}. Neil Crawford said that he would probably have read that Stage C report when he came on to the project. Crawford {Day9/136:9-14}.

¶56.77 Mr Crawford accepted that it had been the architect's duty to ensure that the insulation complied with the Building Regulations^16301630 Crawford {Day10/124:11-20}. and told us that based on his knowledge of Bruce Sounes' work he would have expected Mr Sounes to have checked that FR5000 was suitable before completing the Employer's Requirements.^16311631 Crawford {Day9/140:7-11}. Mr Crawford said that although he did not have any conversations with Mr Sounes about the suitability of FR5000 for use in the external wall, he had gained the impression that Mr Sounes was firm in his view that it was suitable,^16321632 Crawford {Day9/139:14-24}; {Day10/51:11-14}. although he could not recall his saying it in terms.^16331633 Crawford {Day9/140:3-6}. Bruce Sounes, however, could not recall any conversation with Neil Crawford in which he had expressed any view about the suitability of FR5000.^16341634 Sounes {Day20/73:5-17}. In our view it is unlikely that by then Mr Sounes had any lingering doubts about using FR5000, and we therefore doubt that he had any reason to express a view of any kind about the suitability of FR5000 for use in the cladding system.

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¶56.78 Neil Crawford had some recollection of having seen the product datasheet for FR5000 but could not recall when he first saw it.^16351635 {SEA00005841}; Crawford {Day9/142:1-12}. At all events, he did not take any steps to check it when he learnt that FR5000 had been specified for use in the external wall.^16361636 Crawford {Day9/142:14-19}.

The change from FR5000 to RS5000: August to September 2014

¶56.79 On 27 August 2014 Jonathan Roome sent an email to Daniel Anketell-Jones attaching further information about RS5000.^16371637 {CEL00011960}. Mr Roome sent Mr Anketell-Jones a product comparison document, the product datasheet, the LABC Registered Details drawing and document list and certificate, a four-page version of the BRE Global Classification Report on a system which included 100mm RS5000 insulation board, the rainscreen cladding compliance guide, and the rainscreen cladding specification guide.^16381638 {CEL00011960}; {CEL00000007}; {CEL00000411}; {CEL00011963}; {CEL00011415}; {CEL00011965}; {CEL00011966}; {CEL00000418}. Mr Roome was not aware at that time that the full BRE report ran to 12 pages and neither he nor Mr Anketell‑Jones noticed that the four-page report was only a part of the document.^16391639 Roome {Day69/209:10-19}; {Day69/213:2-9}; {Day69/213:10-12}.

¶56.80 Mr Anketell-Jones said that at that time the only thing he knew about insulation was U-values,^16401640 Anketell-Jones {Day36/87:1-15}. but despite his lack of knowledge about the fire performance of different kinds of insulation and his assertion that he would normally send technical information to others for their consideration,^16411641 Anketell-Jones {Day36/93:15-25}; {Day36/94:1-3}; {Day36/97:24-25}; {Day36/98:1-6}. he did not send the package of documents he received from Mr Roome to anyone else within Harley or the wider design team because he did not regard himself as the designer.^16421642 Anketell-Jones {Day36/88:13-19}.

¶56.81 Shortly after receiving the documents from Mr Roome, Mr Anketell-Jones carried out U-value calculations for FR5000 using a piece of software called "BuildDesk".^16431643 Anketell-Jones {Day36/106:5-23}. On or around 28 August 2014 Mr Anketell-Jones and Mr Roome discussed those calculations. Mr Roome recorded their discussions in a note in which he recorded that Mr Anketell- Jones had said that the calculations had been performed using FR5000 but that he needed to use RS5000 at a thickness of 150mm.^16441644 {CEL00001451}. That is the first reference we have seen to the use of RS5000 in place of FR5000 at Grenfell Tower.

¶56.82 Daniel Anketell-Jones was emphatic that he had not selected RS5000 for use at Grenfell Tower.^16451645 Anketell-Jones {Day36/173:2-4}. He explained that the NBS Specification as drawn up by Studio E was a prescriptive specification and the insulation product, RS5000, had been prescribed by Studio E.^16461646 Anketell-Jones {Day36/116:13-17}; {Day36/141:13-16}; {Day36/149:18-19}; {Day36/173:2-4}. However, that was plainly wrong. Studio E had specified FR5000, not RS5000, and Mr Anketell-Jones, like others at Harley, had no reason to think that they were the same product, especially in circumstances where Mr Roome himself thought that they were not. Mr Anketell-Jones thought, without any obvious foundation, that by pressing on with RS5000 Harley was simply adhering to Studio E's specification. He believed that Studio E had already checked that RS5000 was suitable before it sent the NBS Specification to Harley^16471647 Anketell-Jones {Day36/102:2-12}; {Day36/93:5-13}; {Day36/141:22-25}; {Day36/142:1}. and assumed that it had been the subject of desktop studies.^16481648 Anketell-Jones {Day36/102:13-19}. We doubt that he did think that at the time, not least because if he had done so his mistake would have been obvious. The NBS Specification had been completed in January 2014, about eight months before the launch of RS5000. Studio E could not have checked the suitability of RS5000 before the NBS Specification had been finalised because the product did not then exist under that name. We reject Mr Anketell-Jones' evidence about his reason for adopting RS5000 in place of FR5000, although we find it impossible to know what he actually thought at the time, if indeed he turned his mind to the point at all.

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¶56.83 It is unlikely that Jonathan Roome expressly advised Harley that RS5000 was suitable for Grenfell Tower,^16491649 Roome {Day69/191:10-13}. but he accepted that he knew Grenfell Tower was over 18 metres in height^16501650 Roome {Day69/191:5-9}. and that he might well have told Mr Anketell-Jones that the product was suitable for use on such buildings because it was the only product available for that application.^16511651 Roome {Day69/200:3-6}.

¶56.84 Mr Anketell-Jones said that at some point he had been told that FR5000 could not be used but that RS5000 was equivalent,^16521652 Anketell-Jones {Day36/113:8-13}. but he could not recall when he was told that or by whom. He said that the only reason that RS5000 would have been put forward on any project was because it was appropriate for use above 18 metres and was one of the few insulation materials that were capable of achieving the high performance required.^16531653 Anketell-Jones {Day36/154:2-8}. In his mind, there was no difference between FR5000 and RS5000.^16541654 Anketell-Jones {Day36/108:1-6}. However, although he was quite right about that, he had no reason to think so. There had been no conversations between Harley and Celotex which could justify his coming to that view; indeed, quite the opposite. He thought that RS5000 was a new product,^16551655 Anketell-Jones {Day36/102:13-19}. not least because that was exactly what Jonathan Roome had told him. For his part, Mr Roome did not know otherwise, having been induced to think that RS5000 was indeed a new product by those at Celotex who briefed the marketing department. In circumstances where RS5000 was being marketed as a new product there is no credible basis on which Mr Anketell-Jones could have thought that it was the same as FR5000 and that there was therefore no need to investigate its fire performance.

¶56.85 Harley did not consider whether another insulation product, such as a mineral wool, might be more appropriate for use on the project. Mr Anketell-Jones explained that RS5000 had been specified by Studio E and that Harley was not considering any alternative products.^16561656 Anketell-Jones {Day36/119:1-7}. He was not aware whether the fact that RS5000 was rated Class 0 had affected the decision to use it,^16571657 Anketell-Jones {Day36/93:5-13}. but even so, a change from FR5000 to RS5000 ought to have led Harley to investigate why FR5000 had originally been specified, why RS5000 was being substituted and whether it was a suitable product for use on the tower.

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¶56.86 Daniel Anketell-Jones did not ask Rydon or Studio E whether they were happy with the use of RS5000^16581658 Anketell-Jones {Day36/108:17-25}. because he did not consider himself to be the design manager on the project.^16591659 Anketell-Jones {Day36/80:15-17}. He thought that was Ben Bailey's or Kevin Lamb's job as designer^16601660 Anketell-Jones {Day36/108:17-25}. and assumed as a result of having worked with him before that Mr Lamb knew that was his responsibility.^16611661 Anketell-Jones {Day36/66:11-14}; {Day36/74:1-12}; {Day36/105:11-16}; {Day36/73:15-25}; {Day36/73:15-25}. He said that he had expected Kevin Lamb to tell Studio E about the proposed use of RS5000 so that it could check its suitability and Rydon to have then checked with Building Control,^16621662 Anketell-Jones {Day36/79:14-25}; {Day36/80:1-5}. but he did not tell Mr Lamb that that was his responsibility.^16631663 Anketell-Jones {Day36/65:20-25}; {Day36/66:1-10}. For reasons explained below, we do not accept Mr Anketell-Jones' explanation of his role at Harley; in particular, we do not accept that it was as limited as he suggested.

¶56.87 Daniel Anketell-Jones did not have any conversation with Kevin Lamb about the use of RS5000 and did not show him the Celotex documents. He could not explain how Mr Lamb could possibly have been aware of the change from FR5000 to RS5000 to enable him to check the position.^16641664 Anketell-Jones {Day36/109:2-7}. He did not know who at Harley was responsible for reading the Celotex specification guide for RS5000 and suggested that, if Mr Lamb had satisfied himself that RS5000 had been checked by Studio E and Building Control, he would not need to have read it.^16651665 Anketell-Jones {Day36/94:4-12}.

¶56.88 Kevin Lamb was told on 12 August 2014 at his initial meeting with Ray Bailey and Daniel Anketell-Jones that the insulation to be used in the external wall was a rigid PIR- type material. He could not recall whether Celotex had been specifically mentioned but assumed that a product of that kind had been selected.^16661666 Lamb {Day37/77:6-13}; {Day37/81:8-24}. He did not recall seeing FR5000 in the NBS Specification.^16671667 Lamb {Day38/33:25}. There was no discussion between Kevin Lamb and either Mr Bailey or Mr Anketell-Jones about the specification of the insulation product; he was simply told which product had been selected.^16681668 Lamb {Day37/78:25}-{Day37/79:22}.

¶56.89 Kevin Lamb had not previously used a product like Celotex in a rainscreen cladding system.^16691669 Lamb {Day37/80:5-6}. He did not see it as his responsibility to provide advice on compliance with the relevant regulatory requirements, although he said that he had had a brief look at literature relating to the use of Celotex on buildings over 18 metres in height and a brief look at the guidance published by the CWCT.^16701670 Lamb {Day37/130:2-13}. He knew that there was a difference between Class 0 and limited combustibility,^16711671 Lamb {Day38/83:9-12}. but he was not aware that limited combustibility was defined by reference to specific tests.^16721672 Lamb {Day38/83:22-25}; {Day38/84:1-2}. He did not consider the difference and assumed that if a material was rated Class 0 it was suitable for use.^16731673 Lamb {Day38/83:16-17}. He did not know that to comply with paragraph 12.7 of Approved Document B insulation materials used on buildings above 18 metres in height should be materials of limited combustibility.^16741674 Lamb {Day37/150:2-4}. He did not consider it part of his responsibility to review the insulation for compliance with the Building Regulations or Approved Document B.^16751675 Lamb {Day37/160:15-18}; {Day37/165:13-18}; {Day37/170:4-8}. He therefore read the Celotex Rainscreen Cladding Compliance Guide only to review the type of fixings it required within the cladding system.^16761676 {CEL00002047}; Lamb {HAR00010419/14} page 14; Lamb {Day38/36:20-25}; {Day38/37:1-5}.

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¶56.90 Ben Bailey was not familiar with RS5000 but said he had thought that it had always been intended to use it on Grenfell Tower.^16771677 Ben Bailey {Day39/71:13-15}; {Day39/70:19-23}; {Day39/69:6-7}. He thought (though why is not clear) that Studio E had chosen RS5000 for use on Grenfell Tower and possibly that "FR" had been a typographical error in the NBS Specification.^16781678 Ben Bailey {Day39/70:19-23}; {Day39/69:6-7}.

¶56.91 Ben Bailey told us that there he had had a conversation with Neil Crawford in which he had questioned the choice of FR5000 because he had been under the impression that RS5000 was to be used. He said that Neil Crawford had told him that RS5000 had been chosen, which he understood to mean that RS5000 should have been specified and that it was Studio E's intention that RS5000 rather than FR5000 be specified.^16791679 Ben Bailey {Day39/67:6-25}; {Day39/68:1-11}; {Day39/71:3-4}. Ben Bailey said that there had been no discussion between them about the suitability of either FR5000 or RS5000 for use in buildings above 18 metres in height.^16801680 Ben Bailey {Day39/69:8-23}. He said that he had not told Mr Crawford that RS5000 was a new product nor had he asked him whether it complied with the Building Regulations. Neil Crawford merely confirmed, he said, that there was a typographical error in the NBS Specification; he therefore assumed that Studio E had checked the suitability of RS5000.^16811681 Ben Bailey {Day39/73:6-21}. Albeit that Ben Bailey could not recall the exact words used by Neil Crawford. Ben Bailey {Day39/73:20-21}.

¶56.92 The difficulty with Ben Bailey's evidence is, again, that the last version of the NBS Specification was dated 30 January 2014, some eight months before the launch of RS5000. Studio E therefore cannot have intended to specify RS5000. In response to that difficulty, Mr Bailey said that he had misremembered the conversation and changed his evidence to say that Neil Crawford had confirmed his expectation that RS5000 should be the chosen product.^16821682 Ben Bailey {Day39/74:4-13}. Ben Bailey did not take any steps to amend the NBS Specification^16831683 Ben Bailey {Day39/74:15-20}. and he did not ask whether anyone had checked that RS5000 was suitable. He assumed that Studio E had done that.^16841684 Ben Bailey {Day39/72:6-17}; {Day39/72:10}-{Day39/73:2}. He did not consider whether a different kind of insulation might be more suitable for use on Grenfell Tower;^16851685 Ben Bailey {Day39/141:23-25}; {Day39/142:1}. nor did he consider whether the use of a PIR product rather than a mineral wool product might affect fire safety.^16861686 Ben Bailey {Day39/143:2-5}.

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¶56.93 If Ben Bailey did have a conversation with Neil Crawford of the kind he described, he did not tell anyone at Harley about it. Nor did he mention it in his witness statement. Neil Crawford did not mention any such conversation and there is no indication in the documents that Studio E expected RS5000 to be used. For those reasons we do not accept Ben Bailey's evidence on that matter.

¶56.94 Ray Bailey thought that RS5000 was a new product and not a rebranded version of FR5000^16871687 Ray Bailey {Day33/65:3-10}. because that is what Celotex had told him. He told us that either Ben Bailey or Daniel Anketell-Jones had communicated the change to Studio E and that Neil Crawford had then accepted it.^16881688 Ray Bailey {Day33/75:2-7}. He said it had been Harley that had pointed out that there was a difference between FR5000 and RS5000 and that RS5000 needed to be accepted to enable it to be used.^16891689 Ray Bailey {Day33/74:16-23}; Ray Bailey {HAR00010184/8} page 8, paragraph 31. His evidence is at least consistent with the fact that Mr Roome thought that the RS5000 was a new product different from FR5000.

¶56.95 Ray Bailey was not aware of any discussions between Ben Bailey or Daniel Anketell-Jones and Studio E about the substitution of FR5000 with RS5000^16901690 Ray Bailey {Day33/75:8-17}. and he did not himself speak to Neil Crawford or anyone else at Studio E about the change.^16911691 Ray Bailey {Day33/76:7-10}. None of the other Harley witnesses and none of the Studio E witnesses suggested that Neil Crawford, or anyone else at Studio E, had been informed of the change from FR5000 to RS5000 or that Studio E had accepted RS5000 for use on Grenfell Tower, as Mr Bailey maintained. We are therefore unable to accept Ray Bailey's evidence on this question. We conclude that Studio E never investigated the suitability of RS5000 for use at Grenfell Tower and did not accept its use.

¶56.96 Looking at the evidence as a whole, we are satisfied that Jonathan Roome did tell Daniel Anketell-Jones that RS5000 was suitable for use in buildings above 18 metres in height. That was consistent with Celotex's communications strategy and with the evidence given by both Mr Anketell-Jones and Mr Roome himself. We think it unlikely, however, that Mr Roome gave any assurance that RS5000 was suitable for use in the specific cladding system being proposed for Grenfell Tower. None of the witnesses could recall any conversation with Celotex about the proposed construction of the external wall and, at least in September 2014, Mr Roome had not seen any relevant drawings or specifications. He therefore had no basis for giving any specific assurance. Indeed, given the presence in the marketing literature of the warning that the BR 135 classification applied only to the system as tested, we think it unlikely that Mr Roome would have given an assurance of that kind in circumstances where there was a risk that someone in the design team might eventually read it and challenge him.

¶56.97 As it turned out, there was no discussion about that warning. No one at Harley read the marketing literature carefully or sent it to Studio E or Exova to comment on. Harley did not ask Celotex or Studio E whether a desktop study had been done to support the use of RS5000 and did not inquire whether any other members of the design team had asked for a desktop study or other assessment to support the proposed system.^16921692 Anketell-Jones {Day36/101:12-21}. Daniel Anketell- Jones simply accepted what Jonathan Roome had told him about the suitability of RS5000 for use on buildings above 18 metres in height and assumed that it complied with the relevant statutory requirements. On that basis he told Mr Roome that RS5000 was needed for use at Grenfell Tower.^16931693 {CEL00001451}.

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¶56.98 Although Jonathan Roome was canny enough to avoid giving any specific assurance to Harley that RS5000 was suitable for use on Grenfell Tower, we think he suspected that Harley had not understood the warning in Celotex's marketing literature. He certainly never drew Harley's attention to it, which was consistent with Celotex's marketing strategy to downplay it and tuck it away in the small print.^16941694 This is consistent with Mr Roome's internal slides of 11 February 2015 {CEL00003544}.

¶56.99 There was a design team meeting on 2 September 2014 at which U-values were discussed with Rydon. The question arose whether they needed to be rechecked from an M&E and insulation point of view.^16951695 {SEA00011581/4}; {RYD00017128}. A post-meeting note states that the "Max Fordham tender U-value document was shared to team via email". After a discussion everyone agreed to check their calculations. Neil Crawford did not know why Rydon had wanted to recheck the U-values; he understood that they had been derived from Max Fordham's advice but did not recall in any detail how the target had been established.^16961696 Crawford {Day10/66:9}-{Day10/67:4}. Daniel Anketell-Jones and Kevin Lamb also attended that meeting and Mr Anketell-Jones checked the U-values by making another calculation using the "BuildDesk" software.^16971697 Anketell-Jones {Day36/118:11-19}. This time he used RS5000 in the calculation,^16981698 {CEL00000030}. but that did not prompt him to consider its fire safety.^16991699 Anketell-Jones {Day36/118:23-25}.

Harley's Request for Information: September 2014

¶56.100 On 17 September 2014, Daniel Anketell-Jones sent a formal Request for Information to Rydon and Studio E about the extent to which horizontal fire breaks were required within the cladding.^17001700 {HAR00003638/4}; {EXO00001291}. In summary, Harley believed that horizontal firebreaks might be required at every floor level but not in the area between the windows, because there was no "chimney effect" at that location. Daniel Anketell-Jones accepted that he had drafted the request^17011701 Anketell-Jones {Day36/156:25}. but said that he had been asked by someone else to send it and had not fully understood the point. However, he could not remember who had asked him to send it^17021702 Anketell-Jones {Day36/157:6-18}. and said that he did not know what analysis had been done to support it.^17031703 Anketell-Jones {Day36/158:10-13}. We do not accept his evidence on this point. We think he drafted the request in his role as Harley's design manager, part of which did involve considering the fire performance of the external walls which Harley was designing.

¶56.101 Neil Crawford sent the request to Terence Ashton of Exova and asked him to comment on Daniel Anketell-Jones' "interpretation".^17041704 {HAR00003638/4}. Exova was then provided with some Harley drawings and Mr Ashton replied on 18 September 2014 saying that if the insulation in the cavities behind the rainscreen cladding were combustible it would be necessary to provide cavity barriers even if there was no continuous cavity from the top to the bottom of the building.^17051705 {HAR00003638/3}. As we have explained in Chapter 54, that advice was incorrect in so far as it implied that combustible insulation could be used provided cavity barriers were installed.

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¶56.102 Neil Crawford sent that email on to Daniel Anketell-Jones the same day.^17061706 {HAR00003638/2}. Mr Anketell- Jones said that he had read Mr Ashton's response but formed no view about it.^17071707 Anketell-Jones {Day36/162:1-3}. He did not question why Mr Ashton appeared to be linking the combustibility of the insulation to the requirement for cavity barriers.^17081708 Anketell-Jones {Day36/162:3-8}. Mr Anketell-Jones replied to Mr Crawford and Rydon the same day saying that because the insulation was Class 0, he thought that a fire barrier (i.e. a cavity barrier) in those locations would not be necessary and asking for confirmation.^17091709 {HAR00003638/1}. He attached the RS5000 product datasheet to his email.^17101710 {HAR00012103}; {HAR00012104}. That appears to have been the first time that Studio E had been informed of the change from FR5000 to RS5000.^17111711 Anketell-Jones {Day36/163:24-25}; {Day36/164:1-2}.

¶56.103 Daniel Anketell-Jones told us that his message showed that he did not understand fire classifications or know where cavity barriers were required and that he believed that it was the responsibility of the consultants to tell Harley where they needed to be installed.^17121712 Anketell-Jones {Day36/164:25}; {Day36/165:1-4}. We do not accept that Mr Anketell-Jones was as naïve and ignorant as he pretended. In that email, he was giving his opinion of the fire classification of the insulation (Class 0) and whether that meant that fire barriers were necessary in certain locations. It reflects his view of what was meant by Class 0. He said he had not checked his opinion with any of his colleagues or against any published guidance^17131713 Anketell-Jones {Day36/167:2-7}. because he was concerned only with matters of structural engineering.^17141714 Anketell-Jones {Day36/167:7}. It is certainly true that he did not check his opinion with anyone else or against any available guidance, but we doubt whether he made any positive decision not to do so.

¶56.104 Daniel Anketell-Jones said that he had looked at the product datasheet, had seen that RS5000 was rated Class 0, and had passed that on to Studio E and Rydon.^17151715 Anketell-Jones {Day36/166:18-24}. Neil Crawford then asked Mr Ashton to provide his view on whether Class 0 insulation obviated the need for cavity barriers in certain locations.^17161716 {HAR00003638/1}. In response Mr Ashton pointed out that a material which has a Class 0 rating is not necessarily non-combustible although the reverse is invariably true and that it was therefore necessary to prevent the spread of fire from one flat to the flat above. It was not clear from the information he had been given whether there was a continuous cavity from top to bottom in any part of the cladding, irrespective of the type of insulation.^17171717 {EXO00001430}.

¶56.105 Mr Anketell-Jones did not give any consideration to Mr Ashton's advice that, in summary, a Class 0 insulation may not be sufficient for fire safety.^17181718 Anketell-Jones {Day36/170:13-22}. Even having read that advice, it did not occur to him to question whether RS5000 was suitable, as he continued to believe that RS5000 had already been approved by Studio E, building control, and the fire engineer.^17191719 Anketell-Jones {Day36/171:1-5}; {Day36/171:11-12}.

¶56.106 We have already concluded that Daniel Anketell-Jones' professed understanding was wrong and that RS5000 had not been checked for suitability by Studio E, nor had Studio E confirmed that RS5000 was suitable for use at Grenfell Tower. Mr Anketell-Jones' belief that the fire engineer had already approved RS5000 makes little sense, given that Exova itself was inquiring about the type of insulation to be used in the external wall. It is clear that

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¶Exova did not know what insulation it was proposed to use and so could not have already approved it. Accordingly, we reject Mr Anketell-Jones' evidence that he thought that

¶RS5000 had already been approved by Exova. In fact, at no stage did he raise with anyone at Rydon, Studio E or Exova the combustibility of the insulation,^17201720 Anketell-Jones {Day36/171:13-16}. nor did he take any steps following the Request for Information to investigate whether RS5000 complied with the Building Regulations or the guidance in Approved Document B.^17211721 Anketell-Jones {Day36/171:5-12}.

¶56.107 Although Neil Crawford was right to refer some of those questions to Exova, he regarded himself as little more than a post-box and failed to ask himself the question whether the switch to RS5000 was appropriate for Grenfell Tower. Once Studio E had been put on notice that an apparently new product was being proposed, it should have ensured that its fire performance was appropriate. Mr Crawford admitted that he had effectively taken it on trust from Harley that it was.^17221722 Crawford {Day10/48:5-9}. He also said that he had read the Celotex literature and was convinced that it was suitable for use,^17231723 Crawford {Day10/53:5-7}. but, if he did read it, he failed to notice that the product was not of limited combustibility^17241724 Crawford {Day10/50:20-24}. or that the system that Celotex had tested was not the same as the one intended for installation on the tower.^17251725 Crawford {Day10/63:2-8}. We accept Mr Hyett's opinion that Studio E's approach fell below the standards to be expected of a reasonably competent architect exercising reasonable skill and care.^17261726 Hyett {Day65/16:23}-{Day65/19:20}.

¶Harley's request for technical information in respect of

¶RS5000: January 2015

¶56.108 On 16 January 2015, Daniel Anketell-Jones sent an email to Jonathan Roome seeking help with what he described as a "headache" and asking for the test results and certificates for RS5000.^17271727 {CEL00000019/2}. Mr Anketell-Jones said that another client^17281728 Daniel Anketell-Jones did not recall the client, but thought it was likely to have been a main contractor or architect on a project unconnected to Grenfell Tower. Anketell-Jones {Day36/123:23-25}; {Day36/124:1-5}. He considered that it was likely to have been in connection with a job which required Harley to put forward an insulation that would meet certain U-value requirements, Anketell-Jones {Day36/124:18-22}.Show full note wanted to know how RS5000 had been installed when it had been tested in accordance with BS 8414, how it had been fixed, what it had been covered with, and what cladding and supporting structure had been used. The client also wanted to see the certificates and results for the test to BS 476 Part 7. It did not occur to Daniel Anketell-Jones that no one at Harley had asked the same questions in relation to the Grenfell project. Mr Anketell-Jones also said that Harley had been hoping to use RS5000 on most of its other cladding projects and therefore wanted to have the information about testing to hand.

¶56.109 Mr Roome in turn sought the BS 476 test reports from a colleague at Celotex, Jamie Hayes, on 19 January 2015, saying that he could always discuss the BS 8414‑2 test report in person,^17291729 {CEL00000453}. and offered to visit Mr Anketell-Jones at Harley's office to do so. If that discussion had taken place, it would probably have revealed the very limited basis on which RS5000 could be used on buildings above 18 metres in height consistently with the Building Regulations and Approved Document B,^17301730 Roome {Day70/67:2-9}; {Day70/62:8-22}. Jonathan Roome agreed with that proposition. but that discussion did not take place.

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¶56.110 Mr Hayes told Mr Roome that he did not have access to those documents and had passed the request on to Paul Evans or Debbie Berger.^17311731 {CEL00000453}. Whether he had or not, the BS 476 test reports were never provided to Mr Roome, who, of course, was unable to provide them to Daniel Anketell-Jones.^17321732 Roome {Day70/68:18-25}.

¶56.111 Mr Roome did not tell Mr Anketell-Jones that RS5000 could not be used on any of Harley's projects unless the cladding system was, in each case, exactly the same as the one that had been tested.^17331733 Roome {Day70/70:20-25}. Mr Roome accepted that Mr Anketell-Jones had either not read the warnings or had misunderstood them (or even intended to ignore them), but denied that he had realised that at the time.^17341734 Roome {Day70/71:1-20}.

¶56.112 Mr Anketell-Jones understood that RS5000 was not suitable for all rainscreen applications and that the suitability of the product had to be determined in relation to each building individually.^17351735 Anketell-Jones {Day36/128:22-25}; {Day36/129:1-4}. Although he said he had not understood how the suitability of RS5000 was to be determined. Despite his professed understanding, and despite the nature of the questions being asked by the client on the other project, however, he did not consider it important to check whether the proposed system was the same as the one that had been tested. He should have known by January 2015 that whether RS5000 was suitable for use in a particular application depended entirely on whether the proposed system corresponded precisely with the one tested, but he assumed, wrongly, that it depended on how the particular fire consultant or building control officer interpreted the information.^17361736 Anketell-Jones {Day36/129:8-11}; {Day36/129:15-21}.

¶56.113 Daniel Anketell-Jones sent another email to Jonathan Roome on 20 January 2015 saying that he was hoping Celotex could provide the test information since otherwise they would have to change to Rockwool Duo Slab, which would satisfy "the specialists".^17371737 {CEL00000019/1}. Mr Roome responded on 21 January 2015, having discussed his response with his colleagues.^17381738 {CEL00000019}. He attached the full (12-page) BRE Classification Report, the thermocouple data from the test (showing the maximum temperatures recorded during testing) and the RS5000 product information sheet.^17391739 {CEL00000020} (12pp report), {CEL00000021} (thermocouple graphs) and {CEL00000022} (product information sheet). Despite their obvious importance, Mr Roome and Mr Anketell-Jones did not discuss the documents.^17401740 Roome {Day70/76:9}.

¶56.114 The most natural reading of the emails sent by Mr Anketell-Jones on 16 and 20 January 2015 is that he knew that the construction of the external wall was critical when assessing the suitability of RS5000 for the purposes of fire safety. That has led us to doubt his attempts to play down the extent of his knowledge about fire performance testing and the importance of his role within Harley on the Grenfell project. We are satisfied that he understood more about the technical aspects of fire safety than he was prepared to admit and as design manager he should have been responsible within Harley, together with others, for checking the fire performance of the products used in the external wall. Indeed his emails suggest that he suspected that Celotex might not have the test evidence to support the claims being made for RS5000. It is a matter of serious concern, therefore, that he made no comparable efforts to check the suitability of RS5000 for use on the Grenfell Tower project, but merely assumed it without any investigation. He said that he had not read the 12-page BRE report or the thermocouple data Mr Roome had sent to him on 21 January 2015 and had not sent it to Kevin Lamb, Studio E, or anyone else because he thought that had already been done^17411741 Anketell-Jones {Day36/124:23-25}; {Day36/125:1-6}; {Day36/141:5-12}; {Day36/142:2-5}. and that it was not Harley's responsibility to do it.^17421742 Anketell-Jones {Day36/124:7-16}.

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¶56.115 Again we cannot accept his evidence on that point. These exchanges occurred almost a year after the final issue of the NBS Specification. If he believed that RS5000 was a new product, Mr Anketell-Jones cannot have thought that the technical information he had obtained from Celotex had been in Studio E's possession when it specified the insulation material almost a year earlier. We consider that at that point, if not before, Mr Anketell‑Jones ought to have conducted his own research and, if necessary, asked Celotex, Studio E or Rydon whether RS5000 was suitable for use at Grenfell Tower.

Celotex's exploitation of Harley

¶56.116 On 11 February 2015 Jonathan Roome sent Debbie Berger and Paul Evans, a market analysis for RS5000, which split potential customers into three tiers.^17431743 {CEL00003543]; {CEL00003544}. Tier 1 comprised customers who were seen as being of no use to Celotex, because they used only non-combustible products or products of limited combustibility because they were not happy with current test data relating to combustible insulation products.^17441744 {CEL00003544/3}. Tier 2 comprised customers who were willing to consider the use of combustible insulation. By contrast, Tier 3 comprised customers who always used combustible insulation because, in some cases, they were not aware of the 18-metre restriction. In our view the existence of that document shows that Celotex was aware of the differing technical sophistication of potential buyers and that it realised that the market for RS5000 was likely to be limited to those who lacked expertise or expert advice or who did not understand, or had not bothered to investigate, the fire performance of RS5000. That reflects a deeply cynical view that there were ignorant or reckless contractors in the market of whom advantage could be taken without any regard for the safety of occupants. Certainly there is no evidence that the safety of residents played any part in Celotex's thinking on how to sell RS5000, at least when it came to Grenfell Tower.

¶56.117 Celotex regarded Harley as a Tier 3 customer and exploited its willingness to accept what it was told and its lack of interest in understanding when RS5000 could be used safely. It refrained from correcting Harley's misunderstanding and encouraged it to pursue the purchase regardless of the product's suitability for the project in hand. That was not the behaviour to be expected of an honest and plain-dealing manufacturer.

¶56.118 In our view Jonathan Roome suspected that Harley had not understood the contents of the Celotex marketing literature and in particular had failed to understand that RS5000 could not be used on a cladding project unless the proposed system as a whole was exactly the same as the one that Celotex had apparently tested in accordance with BS 8414. As noted above, Jonathan Roome accepted that Daniel Anketell-Jones had either not read the warnings to that effect or had misunderstood them or was proposing to ignore them. In our view he turned a blind eye to the failure of Daniel Anketell-Jones to ask the sort of questions in relation to Grenfell Tower that he had asked in relation to a different project in January 2015. Celotex recognised that Harley was ill-informed, or was acting recklessly, and exploited its lack of interest in the circumstances in which RS5000 could safely be used.

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¶Although it provided Harley with some technical information, it deliberately refrained from any attempt to ensure that Harley was fully informed about the suitability of RS5000, an approach that was entirely consistent with its marketing strategy.

Finalising the specification of RS5000: February to April 2015

¶56.119 Ben Bailey took over as project manager at Harley in February 2015.^17451745 {CEL00000024/2}; Ben Bailey {Day39/84:20-24}. He assumed that RS5000 was suitable for use on Grenfell Tower because the U-value calculations made by Daniel Anketell-Jones all referred to RS5000 and because all the conversations he had had with Jonathan Roome related to RS5000.^17461746 Ben Bailey {Day39/70:1-18}. He said that, although no one at Celotex had expressly confirmed or approved the use of RS5000 in combination with ACM panels, Mr Anketell-Jones had told him that a combination of RS5000 and ACM panels had been checked. He had understood that Mr Anketell-Jones had himself been told that it was suitable for use on the project.^17471747 Ben Bailey {Day39/79:19-25}; {Day39/80:1-12}. However, by February 2015 no one working on the project had made any assessment of the suitability of RS5000, let alone in conjunction with ACM rainscreen panels, and if Mr Anketell-Jones had told Ben Bailey that RS5000 and ACM in combination had been checked, he had no basis for doing so.

¶56.120 On 11 February 2015, Jonathan Roome sent Ben Bailey an email asking for the final construction drawings.^17481748 {CEL00000024/2}. He said that he had done so because if components of the external wall penetrated the insulation that could have an effect on the calculation of the U-value.^17491749 Roome {Day70/17:9-17}.

¶56.121 Ben Bailey responded the same day by providing a link to a folder of drawings.^17501750 {CEL00000024}. He did not ask Mr Roome to review the drawings and advise whether the system was safe from a fire perspective.^17511751 {CEL00000024}. Mr Roome did not examine all the drawings, but simply selected two which showed the insulation.^17521752 Roome {Day70/21:11-21}; {Day70/22:7-22}; {CEL00000456}; {CEL00000457}. He did not note that the proposed cladding panels were not made of cementitious fibreboard, as used by Celotex in the BS 8414 tests on RS5000.^17531753 Roome {Day70/23:10-19}.

¶56.122 Jonathan Roome asked the Celotex technical team to make U-value calculations based on the drawings and sent the information back to Ben Bailey.^17541754 {CEL00000029}; At that time, it appears that the specific width of RS5000 was still under consideration in order to achieve the target U-value {CEL00000025}. He did not turn his mind to the nature of the rainscreen to be used at Grenfell Tower or to whether the construction was compliant with Approved Document B.^17551755 Roome {Day70/33:25}; {Day70/34:1-13}. He was only concerned to check the calculations made by Mr Anketell-Jones in September 2014 to support the target U-value.^17561756 Roome {Day70/34:4-6}. He said that either 200mm of RS5000 or 160mm of RS5000 would be required to produce U-values of 0.15 W/m2K and 0.18 W/m2K respectively.^17571757 {CEL00000025}; {CEL00000027}; {CEL00000028}.

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¶56.123 Mr Bailey replied eight minutes later attaching the calculations Daniel Anketell-Jones had made on 3 September 2014 following the design team meeting the day before.^17581758 {CEL00000030}. Mr Roome looked at them but did not appreciate that the proposed system contemplated the use of ACM rainscreen panels.^17591759 Roome {Day70/25:3-25}. No one at Harley expressly told Mr Roome that the rainscreen was to be Reynobond ACM^17601760 Anketell-Jones {Day36/114:11-14}. and it did not occur to him that the construction of the external wall might be different from that tested in May 2014.^17611761 Roome {Day70/17:18-25}.

¶56.124 The system tested in 2014 had contained 100mm of RS5000 and had been classified on that basis. There was no BR 135 classification in respect of a system that included any thickness of RS5000 other than 100mm.^17621762 {CEL00007961/3}. Mr Roome gave no consideration to the fact that Harley thought it was permissible to use 150mm of RS5000 as opposed to 100mm and did not turn his mind to the fact that the calculations based on 200mm or 160mm of RS5000 meant that the system proposed for Grenfell Tower would not be the same as that tested and would therefore not be covered by the BR 135 classification.^17631763 Roome {Day70/31:1-5}. He said that at the time he had thought that the test related to the individual components of the system and that the classification was valid regardless of the quantity of material used.^17641764 Roome {Day70/30:7-25}. If he thought that, he was wrong, but we do not think his evidence is reliable, not least because it is inconsistent with his earlier evidence and the very warnings in the Celotex literature that he well understood.^17651765 He contradicted his own evidence. Roome {Day69/52:1-9}.

Did Celotex tell Harley that RS5000 was safe to use on Grenfell Tower?

¶56.125 In the course of his evidence Ray Bailey repeatedly asserted that Celotex had told Harley that RS5000 was safe to use on buildings over 18 metres in height. Initially he said that Daniel Anketell-Jones had identified the warning in the Celotex marketing literature and that Harley had taken advice from Celotex about the suitability of RS5000.^17661766 Ray Bailey {HAR00010184/42} page 42, paragraph 170; Ray Bailey {Day33/82:7}-{Day33/83:3}. In the course of giving evidence he told us that Harley had sent details of the construction of the external wall to Celotex so that Celotex could confirm that the use of RS5000 was safe, although it did not expressly ask that question. He said he had thought that Celotex had in effect carried out a desktop study to compare the construction intended for use at Grenfell Tower with what had been tested.^17671767 Ray Bailey {Day33/76:16-21}. He also insisted that Celotex had confirmed that it was safe to use it in that way.^17681768 Ray Bailey {Day33/91:1-2}.

¶56.126 We do not accept Ray Bailey's evidence on that point. We doubt that he was deliberately seeking to mislead us; it is more likely that he had persuaded himself of the truth of a story he had told himself ever since the fire. We are satisfied, however, that Harley did not ask Celotex for a formal assessment of the kind he described and was not given one, let alone an unqualified assurance that RS5000 was suitable for use in the external wall construction proposed for Grenfell Tower, although it certainly allowed Harley to obtain that impression, and knew it. When pressed Mr Bailey himself accepted that he did not know whether Celotex had provided any such assessment.^17691769 Ray Bailey {Day33/78:4-10}. He knew that the classification report based on the BS 8414 test applied only to the system tested^17701770 Ray Bailey {Day33/85:18-21}. and he knew that that system differed from the system proposed for Grenfell Tower.^17711771 Ray Bailey {Day33/86:1}-{Day33/87:6}. It is hard to understand, therefore, on what basis he could possibly have thought that RS5000 was suitable for use in the external wall system at Grenfell Tower. For its own part, Harley cannot avoid responsibility for its own failures by blaming Celotex for not telling it what it should have known or discovered for itself.

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April 2015: further discussions

¶56.127 On 8 April 2015 Jonathan Roome sent BCA Technical Guidance Note 18, issue 0 to Daniel Anketell-Jones.^17721772 {CEL00003628}. Mr Anketell-Jones said that he had not previously seen it and had not read through it.^17731773 Anketell-Jones {Day36/147:16-18}. The additional information should have led him to look again at the documentation sent to him by Celotex in August 2014, but he did not do so.^17741774 Anketell-Jones {Day36/127:11-14}.

¶56.128 Jonathan Roome told us that he had thought at the time that Harley was adopting the desktop study route to compliance with the Building Regulations, as set out in Approved Document B.^17751775 Roome {Day70/80:21-24}. However, he had not seen any desktop study relating to the proposed external wall of Grenfell Tower, or any reference to one.^17761776 Roome {Day 70/81:2-14}. In fact, none existed and Mr Roome had no grounds for thinking that that was Harley's chosen approach. We do not accept that he formed any view at the time about how Harley intended to demonstrate compliance with the Building Regulations or that he cared. He suspected that Harley had either not read or not understood the warning in the Celotex marketing literature and pursued the sale regardless of the consequences.

The first order of RS5000 for Grenfell Tower

¶56.129 SIG was one of a small number of major distributors of Celotex and other insulation products^17771777 Roome {Day69/71:19-23}. and supplied RS5000 for use at Grenfell Tower. SIG invoiced Harley for its first order of RS5000 on 1 April 2015.^17781778 {SIG00000022}.

Grenfell Tower as a "case study"

¶56.130 On 8 April 2015, Jonathan Roome met Ben Bailey at Harley's offices.^17791779 {CEL00000039}; {CEL00001443}. By then the first batch of RS5000 had been delivered to site but installation had not yet begun. Mr Roome proposed that Grenfell Tower could be used as a case study because it was one of the first major projects in which RS5000 was being used on a building above 18 metres in height.^17801780 Harley agreed. {CEL00000039}; Roome {Day70/38:10-21}; {CEL00001443}; Roome {Day70/40:1-25}; {CEL00000558}; {CEL00000566}. Roome {Day70/41:19-23}, and the first project for Jonathan Roome. {Day70/43:4-7}. Ben Bailey thought that any case study would focus on the U-value which could be achieved using RS5000.^17811781 Ben Bailey {Day39/92:9-25}; {Day39/93:15-17}. Despite intending to publish a leaflet describing the product and its use on the tower, Mr Roome did not ask Mr Bailey what the rainscreen was to be.^17821782 Roome {Day70/41:1-10}. Ben Bailey knew that RS5000 had not been widely used before, but he did not realise that Grenfell Tower was being treated by Celotex as a flagship project for the use of the product, although the very suggestion that it be treated as a case study might have alerted him to that fact.^17831783 Ben Bailey {Day 39/93:12}-{Day39/94:15}.

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¶56.131 Kingspan K15 insulation was used in substitution for RS5000 on Grenfell Tower from time to time when Harley encountered problems with the supply of RS5000. It was used in much smaller quantities than RS5000, but the amount was not insignificant. Photographs indicate that it was certainly used on the west side of the tower,^17841784 {RYD00055130} showing west face where Kingspan logos can be seen on some insulation panels, and see Hughes {Day27/147:19}-{Day27/148:23}. but the precise locations where it was used are not known and cannot be established given that much of the insulation was consumed in the fire.

¶56.132 K15 was not included in the NBS Specification and no substitution of materials described in the Employer's Requirements or Contractor's Proposals was permitted without the prior written consent of the TMO. It was Rydon's responsibility to obtain that consent, but it failed to do so in relation to the substitution of K15 for RS5000.

The decision to use K15: March – September 2015

¶56.133 Although Studio E was in possession of a product datasheet for K15^17851785 {SEA00001009}; Sounes {Day12/188:2-7}. and both Bruce Sounes and Neil Crawford were aware of the product, neither of them knew until after the fire that it had been used on Grenfell Tower.^17861786 Crawford {Day10/139:21}-{Day10/140:10}. Sounes {Day12/189:3-11}. They are not to blame for that, since they were never consulted about it, either by Harley or Rydon, and had no other means of knowing.

¶56.134 Harley was familiar with K15, having used it before on its Merit House^17871787 Ben Bailey {Day39/31:23}{Day39/32:3}; {Day39/142:11-14}. and Wayland House projects.^17881788 Ray Bailey {Day33/19:20}-{Day33/20:7}. On 4 March 2015, Mark Stapley of Harley sent SIG an email requesting a quotation for K15 for comparison purposes with RS5000.^17891789 {HAR00010030}. Quotation is at {HAR00009721}; {HAR00009722}; Ben Bailey {Day39/108:3-7}. Ben Bailey could not remember having talked to Mr Stapley about it; nor could he remember why Mr Stapley wanted a price for an alternative product.^17901790 Ben Bailey {Day39/104:10-18}. On 9 March 2015, he sent Mr Stapley an email to which he attached a leaflet relating to a different Kingspan insulation product.^17911791 {HAR00009643} attaching {HAR00009644}, a brochure for Kingspan OPTIM-R which made clear, on page 7, that K15 was suitable for use in buildings over 18 metres. One can see, therefore, that K15 and other products were being considered for use on the project as early as March 2015,^17921792 {HAR00009721}; Ben Bailey {Day39/108:3-7}. but no K15 was ordered at that time.

¶56.135 On 26 May 2015, Ms Walker of SIG sent an email to Ben Bailey explaining that a delivery of RS5000 that had been arranged for 3 June 2015 would be delayed until 10 June.^17931793 {SIG00000013/2}. Mr Bailey replied, asking whether SIG held K15 in stock at the same thickness.^17941794 {SIG00000013/2}. He told us that before receiving that email Ms Walker had told him that SIG had problems with obtaining products from Celotex and that in the course of their conversation Ms Walker had suggested K15 as an alternative,^17951795 Ben Bailey {Day39/110:23}-{Day39/111:23}; {Day39/113:18-21}. as being equivalent to RS5000.^17961796 Ben Bailey {Day39/109:11-20}.

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¶56.136 We accept that Harley decided to substitute K15 for RS5000 because of difficulties obtaining RS5000 on time,^17971797 The evidence of all the relevant Harley witnesses was that the substitution was motivated by supply chain issues: Ray Bailey {HAR00010184/29} page 29, paragraph 114; Ben Bailey {HAR00010060/8} page 8, paragraph 26; Ben Bailey {Day39/113:4-6}; Lamb {Day38/38:8-25}. but we do not accept that Mr Bailey had a telephone conversation with SIG of the kind he described. Mr Bailey's response to Ms Walker's email of 26 May ("Are you joking?!")^17981798 {SIG00000013/2}. conveys an immediate reaction, not one that followed a telephone call during which he had already been told about the delay. Moreover, if Ms Walker had discussed with him the suitability of K15 as an alternative, it is likely that she would have referred to it in her next email. We think it much more likely that the use of K15 as an alternative to RS5000 was suggested by Ben Bailey in his reply to Ms Walker. We do not accept that she told him at any time that K15 was an equivalent product to RS5000.

¶56.137 Ray Bailey told us that K15 had been investigated and approved for use on high-rise buildings in in 2010 or 2011 by Graham Hackley, who was then Harley's Technical & Estimating Manager^17991799 Ray Bailey {Day32/16:6-16}; {Day32/17:10-23}; {Day32/18:3-5}; {Day33/19:6}-{Day33/20:9}. It was signed off as being "for use pretty much on all projects" {Day33/100:2-5}; {Day33/100:10-11}. and that no further checks on its suitability had been made since it had received his approval.^18001800 Ray Bailey {Day33/30:2-3}; {Day33/99:6-10}. However, Mr Bailey conceded that there was nothing in the documents to support the conclusion that Mr Hackley had undertaken any such investigation or provided any such approval.^18011801 Ray Bailey {Day33/100:10-22}. In any event, Ray Bailey described K15 as a standard insulation product throughout the industry for tall buildings.^18021802 Ray Bailey {Day33/98:21-25}.

¶56.138 Ben Bailey was confident about using K15 because Harley had used it on other projects.^18031803 Ben Bailey {Day39/124:16-18}; {Day39/124:25}-{Day39/125:5}. He shared his father's understanding that K15 could be used on high-rise buildings^18041804 Ben Bailey {Day39/56:4-7}. and in combination with any rainscreen.^18051805 Ben Bailey {Day39/102:18-21}. He did not look at the LABC certificate^18061806 {KIN00016733}. Ben Bailey {Day39/126:2-5}. He was not aware of the LABC as a body {Day39/126:11-13}. or the relevant BBA certificate;^18071807 {KIN00000454}. The 2013 version. indeed, Harley had on file only the 2008 version of the BBA certificate, which by June 2015 was more than five years old and had been superseded.^18081808 {BBA00000038}. Ben Bailey did not know that the BBA certificate was out of date, a second certificate having been issued in 2013 {BBA00000036}; Ben Bailey {Day39/119:5-19}.

¶56.139 Ben Bailey's evidence was that following receipt of Ms Walker's email he had checked the U-values achievable by K15 and had looked at the 2008 BBA certificate or the product literature to check that it was rated Class 0, but no more than that. He said that he had made those enquiries in the office alongside Daniel Anketell-Jones and Mark Stapley.^18091809 Ben Bailey {Day39/117:6-11}; Ben Bailey {Day39/117:22-25}; {Day39/118:1-16}; {Day39/119:1-4}.

¶56.140 Daniel Anketell-Jones told us that he had not been aware that K15 had been used on Grenfell Tower,^18101810 Anketell-Jones {Day37/1:23}-{Day37/2:2}. which, if true, casts some doubt on whether Ben Bailey really did make the enquiries to which he referred. The first purchase order for K15 appears to have been sent to SIG within an hour of Ms Walker's initial email,^18111811 {SIG00000012}; {SIG00000013}; Ben Bailey {Day39/116:17-18}. so any research or investigation conducted by Ben Bailey must necessarily have been very limited. He did not consider whether the cladding system proposed for Grenfell Tower was the same as that which had included K15 and had apparently met the criteria in BR 135 following a test in accordance with BS 8414.^18121812 Ben Bailey {Day39/127:21-25}.

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¶56.141 Ray Bailey accepted that Harley had not investigated whether there was any test evidence which showed that K15 was of limited combustibility^18131813 Ray Bailey {Day33/102:17-25}. and agreed that Harley ought to have made further enquiries about the combustibility of K15 before using it on Grenfell Tower.^18141814 Ray Bailey {Day33/103:7-18}. There was nothing in the 2008 BBA certificate^18151815 {BBA00000038}. to confirm that K15 was a product of limited combustibility and nothing to indicate that it was appropriate for use in any configuration of cladding system. In short, the literature did not show that K15 was safe for use on Grenfell Tower.

¶56.142 Harley placed two orders for K15: 96 units with SIG on 26 May 2015^18161816 {SIG00000012}; {SIG00000013}. and 49 units with CCF on 10 September 2015.^18171817 {CCF00000019}. Hugh Bailey, a project manager at Harley, asked CCF for a further 60 units on 10 September 2015, but no purchase order or invoice was raised in respect of that quantity.^18181818 {CCF00000015}.

¶56.143 Ben Bailey did not consider finding an alternative supplier for RS5000 because he thought it would take too long to open a credit account with a new supplier.^18191819 Ben Bailey {Day39/128:10-20}. He thought that the week-long delay to the supply of RS5000 was critical to the programme and Harley was under pressure from Rydon to keep up progress in accordance with the programme of works.^18201820 Ben Bailey {Day39/130:12-13}; {Day39/131:13-17}.

¶56.144 Ben Bailey said that in May 2015,^18211821 Ben Bailey {Day39/152:6-13}. he had spoken to Simon Lawrence or Simon O'Connor about the substitution of K15 for RS5000. He said that they had discussed the U-values of both products and the fact that they were both rated Class 0.^18221822 Ben Bailey {Day39/129:15-21}. Ben Bailey said that Mr Lawrence had understood the reason for the substitution and had agreed to it immediately.^18231823 Ben Bailey {Day39/152:14-21}. There had been no mention of the need to obtain Rydon's express consent.^18241824 Ben Bailey {Day39/129:22-25}.

¶56.145 The recollections of Mr Lawrence and Mr O'Connor differed substantially from that of Mr Bailey. They both said that they had been unaware of the use of K15^18251825 Lawrence {Day24/138:22-23}; {Day24/139:1-21}; {Day24/148:1-10}; {Day24/148:12-18}; {Day24/149:2-20}; {Day24/151:20-21}; O'Connor {Day26/98:8-11}. and Mr Lawrence said that he had not been aware that Harley had ever sought permission for the use of K15.^18261826 Lawrence {Day24/150:3-12}. Mr O'Connor also said that he had not been aware of any discussions about a substitution.^18271827 O'Connor {Day26/110:10-13}; {Day26/111:10-14}. They accepted that Rydon had to obtain the TMO's permission before substituting any product specified in the NBS Specification and that Harley was obliged to obtain the written approval of Rydon before any alternative insulation product could be used in the external wall envelope.^18281828 {INQ00011211/8} condition 2.4.1; Lawrence {Day24/147:2-5}. Simon Lawrence accepted that obtaining consent from the TMO was his responsibility during his time on the project.^18291829 Lawrence {Day24/147:6-17}.

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¶Mr Lawrence, Mr O'Connor and Mr Blake of Rydon said that the usual course would have been to confirm compliance with the architect before obtaining the written consent of the client to the substitution.^18301830 Lawrence {Day24/156:11-14}; O'Connor {Day26/111:6-9}; Blake {Day29/116:11-18}; {Day29/116:19}-{Day29/117:11}.

¶56.146 Ben Bailey said that Mr Lawrence had agreed to the substitution immediately, but that was not something he was entitled to do. He knew that the suitability of any substitute would need to be confirmed by Studio E before receiving the consent of the TMO. In those circumstances, we think it unlikely that Mr Lawrence would have agreed to the use of a new product without alerting Mr Bailey to the need to refer the proposal to Studio E for comment. If there had been such a conversation we are confident that it would have been recorded, or at any rate mentioned in some way, in one of the contemporaneous documents, but there is no such record and in those circumstances we are unable to accept Mr Bailey's account. We are satisfied that Ben Bailey acted on his own initiative to substitute K15 for RS5000 in order to avoid a delay to the programme. Harley's previous use of the product had led him to believe that K15 was suitable for use on high-rise buildings in conjunction with any rainscreen system. That assumption was, however, wrong.

¶56.147 It is not clear to us why a delay of a week was thought to make a sufficient difference to justify using a product that had not been specified and had not been considered by the design team as a substitute for one that had been prescribed in the NBS Specification and had been used extensively on the project. We think that Ben Bailey, who was a young and inexperienced site manager, succumbed to pressure, actual or perceived, from the main contractor to keep up with the construction programme. He thought that K15 was essentially the same as RS5000 and in his mind there was no reason to think that it was unsafe.

The further use of K15: December 2015

¶56.148 In December 2015 or January 2016 David Hughes of Rydon discussed the use of a Kingspan insulation product with Ben Bailey who was again having difficulty obtaining RS5000.^18311831 Hughes {RYD00094213/10} page 10, paragraph 55. Mr Bailey had sent him the K15 product datasheet and he read it to check that the U-value that could be achieved with K15 was similar to that which could be obtained using RS5000.^18321832 Hughes {Day27/58:10-19}; {Day27/63:25}; {Day27/64:1-16}. He had described it as a "like-for-like" swap.^18331833 Hughes {Day27/58:21-25}; Ben Bailey's evidence was that it was "a common thought" within Harley that K15 and RS5000 were equivalent products: Ben Bailey {Day39/107:1-3}; {Day39/108:11-19}. Mr Hughes thought that Mr Bailey was asking his permission to use K15 in the future^18341834 Hughes {Day27/59:17-24}; {Day27/60:5-9}; {Day27/63:23-25}; {Day27/66:21-22}; {Day27/71:7-11}. and agreed that he could.^18351835 Hughes {Day27/71:23}-{Day27/72:1}. Shortly afterwards Mr Hughes told Stephen Blake and the clerk of works, Jon White, about the substitution.^18361836 Hughes {Day27/66:6-18}.

¶56.149 K15 had first been ordered and supplied in May 2015, at least seven months before Mr Hughes' conversation with Ben Bailey, and again in September 2015. Mr Hughes said he had no recollection of those orders and did not know that K15 had already been used on the tower.^18371837 Hughes {Day27/148:12-16}. It is therefore very difficult to understand why Mr Hughes should have been asking Mr Bailey about the suitability of K15 and, at least in his mind, giving Mr Bailey permission to substitute K15 for RS5000 when K15 had been used on two occasions some months earlier.^18381838 Ben Bailey's explanation was that the discussion had been prompted by a change in site management. Ben Bailey {Day39/136:18}-{Day39/137:25}. For his part, Mr Bailey did not recall giving Mr Hughes the datasheet on

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¶K15, or indeed any discussion with Mr Hughes about it.^18391839 Ben Bailey {Day39/136:1-11}.

¶56.150 Having considered all the evidence, we have come to the conclusion that Rydon did not become aware of the use of K15 until December 2015 or January 2016, long after it had first been installed on parts of the facade. However, photographs from September and November 2015 clearly show Kingspan insulation on the building^18401840 {RYD00051704}; {RYD00055130}. and Rydon could have noticed that, if it had bothered to look.

¶56.151 Stephen Blake told us that he had become aware that a quantity of K15 was being used on the building towards the end of the project^18411841 Blake {Day29/109:12-21}. and agreed that he had discussed the matter with David Hughes. He was not able to recall that conversation in any detail, however, or when it had occurred.^18421842 Blake {Day29/14:14-25}; {Day29/111:1-11}; {Day29/112:8-13}. Mr Blake said that Mr Hughes had told him that the Kingspan and Celotex products were equivalent and that he had accepted that.^18431843 Blake {Day29/111:13}-{Day29/112:3}. Mr Blake assumed that K15 was equivalent in every respect to RS5000 and did not take any steps to establish its suitability for use on the project.^18441844 Blake {day29/115:7-16}. In fact, he thought that Mr Hughes was describing the same material manufactured by different companies.^18451845 Blake {Day29/113:3-4}. He acknowledged that he ought to have checked for himself whether the products were essentially the same.^18461846 Blake {Day29/113:10-14}.

¶56.152 None of the Rydon witnesses had ever seen the LABC or BBA certificates for K15 and they did not investigate the suitability of K15 for use on Grenfell Tower.^18471847 {KIN00016733}; {KIN00000454}. Lawrence {Day24/155:4-8}; O'Connor {Day26/109:2-6}; Hughes {Day27/59:1-6}; Hughes {Day27/64:17-21}; Hughes {Day27/65:1-6}; Hughes {Day27/147:12-17}; Blake {Day29/114:17}-{Day29/115:16}. No one at Rydon consulted Studio E about the substitution; nor did Rydon take any advice from Exova or any other fire engineer to confirm that K15 was safe for the intended use. There was, therefore, a complete failure on Rydon's part to investigate the suitability of K15 for its intended use. After it had become aware that K15 was being used, Rydon relied on Ben Bailey's assurance that K15 was an equivalent product to RS5000, which everyone assumed was suitable.^18481848 Blake {Day29/118:14-18}; {Day29/119:9-10}; {Day29/119:22-24}.

¶56.153 Neither Mr Hughes nor Mr Blake consulted the TMO or informed building control that a substitution was going to be, or had in fact been, made.^18491849 Blake {Day29/117:13-17}; Hughes {Day27/67:5-8}; Hughes {Day27/67:17}-{Day27/68:8}. Mr Hughes thought that K15 and RS5000 were very similar and that the substitution did not make any difference.^18501850 Hughes {Day27/68:1-8}; Hughes {Day27/70:4-5}. Building control was not provided with any document which showed that K15 was being used as insulation and no attempt was made to obtain the TMO's consent to the substitution at that or any other stage.

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