Dr Barbara Lane of Arup gives expert fire engineering evidence. She explains fire safety systems, the design guidance CP3 1971, and examines the external cladding construction. Identifies 'multiple catastrophic fire routes' and concludes no cavity barriers were present around windows - 'they don't appear to have been considered'.
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00:08:00 good morning everyone welcome to today's hearing we're going to continue with inquiries experts I think we're going to hear from dr. Lane yes good morning mr.
00:08:12 hear from dr. Lane yes good morning mr. chairman thank you yes today and continuing into Monday we're going to be hearing from dr. Lane and then later next week we will be hearing from the other inquiry experts at Phase one including dr. Duncan Glover professor
00:08:25 including dr. Duncan Glover professor Neve Nick Dade and professor purser so can I now call dr. Lane
00:08:50 I swear I swear by Almighty God that the evidence I shall give but the evidence I shall give shall be the truth shall be the truth or truth the whole truth and
00:09:01 the truth or truth the whole truth and nothing but the truth thank you very much dr. Lee sit down make yourself comfortable
00:09:23 yes please can you give the inquiry your full name
00:09:26 full name dr. Barbara Ann Lane thank you dr. Lane this is the continuation of your formal evidence in phase one of the inquiry following your presentation previously on the 18th of June this year at phase
00:09:39 on the 18th of June this year at phase one you were asked to identify the active and passive fire protection measures within the tower and report on the extent to which they failed to control the spread of fire and smoke and
00:09:50 control the spread of fire and smoke and contributed to the speed at which the fire spreads is that correct that's correct and you produced an initial phase one report on the 12th of April this year which consisted of 21 chapters
00:10:01 this year which consisted of 21 chapters and 11 appendices a to K and since that time you have revised and updated that report including in the light of some of the factual evidence that the inquiry has been hearing at phase one your
00:10:14 has been hearing at phase one your revised report is dated the 24th of October 2018 and the conclusions in Section two add a to the 5th of November 2018 is that correct that's correct and
00:10:25 2018 is that correct that's correct and it consists of 21 chapters and 15 appendices a to O and the references without is B la s6 zeros 1 through 2 B
00:10:37 without is B la s6 zeros 1 through 2 B LA s60 36 inclusive is that correct that's correct and you've also recently produced a short Corrections and addendum document dated the 19th of
00:10:48 addendum document dated the 19th of November 2018 that's B la s6 zeros sorry five zeros 37 is that correct that's correct thank you now as you indicate in the declaration
00:10:59 now as you indicate in the declaration in section 21 of your report you have provided it in the same way as he would have provided a report to a court is that right yes I have and in section 1.1
00:11:10 that right yes I have and in section 1.1 an appendix a to your report you've outlined your background and expertise relevant to matters in this inquiry in terms of some of the key points from that you are a director of Arup which is
00:11:22 that you are a director of Arup which is an independent company of designers planners engineers consultants and technical specialists addressing professional services in the built environment is that that's correct and you specialize in
00:11:33 that's correct and you specialize in fire safety engineering in the built environment and you have 20 years experience in the construction industry in England and internationally yes I have you are a chartered fire safety
00:11:46 have you are a chartered fire safety engineer having graduated from Trinity College Dublin yes I don't know and I am you are a fellow of Arup which is an honorary title awarded to exceptional individuals within the firm he correct
00:11:58 individuals within the firm he correct and you also a fellow of the Royal Academy of Engineering and the Royal Society of Edinburgh I am and you've been involved in a number of landmark high-rise buildings including the
00:12:11 high-rise buildings including the following as project director for the shard responsible for on-site compliance works regarding the approved fire strategy is that correct and project
00:12:22 strategy is that correct and project director responsible for developing fire strategies in relation to a number of the Canary Wharf high-rise building that's correct and you were also the fire project director for Elizabeth house a mixed-use high-rise development
00:12:35 house a mixed-use high-rise development in London including commercial residential and retail accommodation yes that was a planning project you know and you were also an expert appointed to
00:12:46 you were also an expert appointed to investigate the collapse of the World Trade Center seven is that correct correct
00:12:51 correct thank you are the factual matters set out in your updated report true to the best of your knowledge and belief yes they are and does this updated report accurately set out your opinions on
00:13:03 accurately set out your opinions on matters relevant to this inquiry yes it does thank you now in terms of the structure of my questioning I'm going to ask you about some of the key conclusions in your phase 1 report in
00:13:16 conclusions in your phase 1 report in the course of that I'm going to ask you to explain some of the aspects in which you've updated your main report in your revised phase 1 report okay I'm also going to seek to identify with you the
00:13:28 going to seek to identify with you the extent to which your investigations are ongoing and some of the particular areas that you wish to investigate further at phase 2 of the inquiries work okay in general I'm going to try and follow the
00:13:41 general I'm going to try and follow the structure of your report as you have set it
00:13:43 it and broadly in the order in which it appears and that will mean that today we're going to focus predominantly on the external facade of the tower okay including the windows and also looking
00:13:55 including the windows and also looking at key timing events in the progression of the fire externally and then it's likely that day two of your evidence on Monday is going to focus in more detail on some of the active and passive fire
00:14:07 on some of the active and passive fire safety systems inside the tower including flat and stair doors the fire main and active systems including the lifts and smoke control system is that does that make sense yep now a lot of the material in chapters 3
00:14:20 now a lot of the material in chapters 3 & 4 of your report tells of the background to the tower and the background to the letters to regime it was covered in your presentation on the 18th of June which forms part of your
00:14:31 18th of June which forms part of your evidence today and I'm not proposing to repeat all of the detail of the outside today so I want to start by looking at your overall approach to the active and
00:14:42 your overall approach to the active and passive fire safety systems and I want to be clear at the outset how you have approached your assessment of those systems at Grenville tower in phase 1 of your report now is it correct to say
00:14:55 your report now is it correct to say that throughout the vast majority of your report you've assessed the active and passive fire safety systems against two key things first the design guidance cp3 1971 which is the guidance that
00:15:08 cp3 1971 which is the guidance that applied at the time of construction of ground fault hour and which you have concluded was applied by the designers to demonstrate compliance with the london building act 1939 yes that's correct
00:15:19 correct along with the other relevant regulation yeah yeah I'm going to come together yeah so the first thing is CP 3 1974 I look at that in a moment yeah and then the second is current statutory guidance
00:15:30 the second is current statutory guidance made pursuant to the Building Regulations 2010 as contained in the prescriptive document which is approved document b fire safety vol 2 is that correct that's correct thank you so let's go back to the 1970s and look
00:15:44 so let's go back to the 1970s and look at the regime which applied when Granville tower was first designed and built in the early night seventies yeah now we believe that gram filter was designed as far as we know between around 1967 and 1972 yes is that
00:15:59 between around 1967 and 1972 yes is that right that's as I understand yeah and we take that from a RB KC chronology which has been provided to the inquiry yes and can you confirm that London was not
00:16:10 can you confirm that London was not subject to National Building Regulations at that time that's correct it was the London Building Act 1939 and relevant bylaws including the London building constructional amending bylaw
00:16:23 building constructional amending bylaw 1964 number one that applied is that correct that's correct thank you and in assessing the original design of Granville tower is it right that you've considered both relevant London guidance
00:16:36 considered both relevant London guidance and also relevant national guidance which may have been applicable at the time yes so in my assessment of Granville tower a building and that part of London and at that height is
00:16:49 of London and at that height is controlled by three sections in the London building act number 20 number 34 and 98 yeah and in looking at those three I then ended up having to look at
00:17:03 three I then ended up having to look at night the 1971 CP 3 because of how I found Granville Tyre to be constructed to document your findings in its physical condition yes so in terms of
00:17:16 physical condition yes so in terms of London guidance yeah at that time you've explained in your report that this is this principally consisted of some London County Council guidance means of escape in case of fire 1954 amended in
00:17:30 escape in case of fire 1954 amended in 1967 yes can you refer to that in your report as the LCC 1967 yes I do yeah and is it right that in 1967 when this was amended it was actually the Greater London Council that amended it
00:17:42 Greater London Council that amended it because it didn't the LCC didn't exist anymore yeah so well it's just it's a very small point but the GLC published that revision yep but the original note
00:17:53 that revision yep but the original note that they republish had LCC on the top so it's a
00:17:57 so it's a it's a very minor point yeah and that London guidance at the time also consisted of the DLC the Greater London Council section 20 code of practice you just talked about - variety of the 1939
00:18:10 just talked about - variety of the 1939 act 1970 and that gave guidance relevant to section 20 of the 1939 act and was a code of practice for buildings of excess height or additional cubical extent
00:18:22 height or additional cubical extent correct so that's the relevant London guidance but at the same time you've explained that there was relevant national guidance is that correct that's correct at the time the Public Health
00:18:34 correct at the time the Public Health Act 1961 and relevant Building Regulations in 1965 like nationally yes that's correct now that national guidance on fire precautions was produced in in 1962 in
00:18:47 precautions was produced in in 1962 in the form of the British Standards institution BSI code of practice cp3 1962 yes correct that's correct that's it's long title is chapter four
00:18:59 it's long title is chapter four precautions against fire part 1 fire precautions in flats and maser nets over 80 feet in height yes so that's CP 3 1962 but then that national guidance was
00:19:11 1962 but then that national guidance was revised in 1971 and was CP 3 1971 is that correct correct and that was called chapter 4 warn code of basic data for
00:19:22 chapter 4 warn code of basic data for the design of buildings precautions against fire flats and amazing nets and blocks over two stories is that correct that's correct so you've explained in your report that this meant at the time there was an
00:19:34 this meant at the time there was an overlap in relevant guidance for firefighting provisions in a single staircase high-rise building at that time is that correct that's correct and you note that when the LCC guide was
00:19:47 you note that when the LCC guide was amended in 1967 the GLC actually issued a statement saying that the gut the guidance was under revision and pending its revision applicants should discuss proposed schemes with the
00:19:58 should discuss proposed schemes with the GLC is that right that's correct from a means of escape perspective yes so in your opinion during this period of transition is it possible that designers
00:20:09 transition is it possible that designers could use either the London guidance principally the LCC guide or the National guidance cp3 1962 or 1971 yes I consider that to
00:20:21 cp3 1962 or 1971 yes I consider that to be the case now you've assessed the design of Graham for tower against these three guidance documents and you've concluded that whilst all three guides permitted a
00:20:33 whilst all three guides permitted a residential building to be constructed with a single stair four means of escape that both the LCC 1967 and CP 3 1962 each required specific conditions to be
00:20:46 each required specific conditions to be met with a single stair and these were not provided at Greenville tower is that correct
00:20:53 correct I'm going to take you through this in detail if that helps okay they didn't allow a single stair but anyway a flag
00:21:04 allow a single stair but anyway a flag onto it so probably being a bit four done okay yeah so the question is understood yeah let's take CP 3 1962 you've explained that three conditions were necessary to be satisfied yeah and
00:21:15 were necessary to be satisfied yeah and that none of these were present at ground floor tower that's correct and is it right that this is essentially because the staircase at Granville tower is accessed by a central ventilated
00:21:27 is accessed by a central ventilated lobby I a single lobby arrangement that you say you don't think could have complied with CP 3 1962 yeah that's that's correct it required the stair at an external surface for external
00:21:41 an external surface for external ventilation yeah can we just look at your summary of the reasons you gave for that in your report let's go to your report that's B la s60 is for at page 20
00:21:54 report that's B la s60 is for at page 20 and if we can zoom in on paragraph four point to point 18 at the top so these are the ways that you're explaining that Graham thought
00:22:06 you're explaining that Graham thought our can't comply with the guidance in CP 3 in 1962 is that correct yes that's correct
00:22:14 correct yep so if we just take each so what you're saying is section 208 yeah part c1 the ventilated lobby is not a balcony yeah because the concept was
00:22:25 a balcony yeah because the concept was if even if you had a single central stair you had to still have an alternative access point to that stair by means of a balcony and that is not a ground filter yeah and then the second
00:22:38 ground filter yeah and then the second point is that Granville Tower the ventilated Lobby doesn't adjoin an external wall in which there's a parent opening of not less than 15 square that's correct and the third point is that the the
00:22:51 and the third point is that the the ventilated Lobby does not communicate with the staircase through a smoke stop door off a balcony or ventilated lobby adjoining an external wall in which is a permanent opening of not less than 15 square feet that's right so those three
00:23:04 square feet that's right so those three things I'm telling you that you don't think it's cp3 in 1962 yeah those three things tell me absolutely that 1962 the 1962 version was not used yep
00:23:15 1962 version was not used yep whereas you say that cp3 1971 the later revised guidance permitted a single stairway and with a cross ventilated single Lobby is that correct that's
00:23:27 single Lobby is that correct that's correct
00:23:28 correct and you say that if we stick with this page just further down on for point two point twenty one who zoom in on that so there you saying that CP 3 1971
00:23:41 there you saying that CP 3 1971 permitted blocks of flats and maser nets to be provided with a single stairway for means of escape through a stage to escape route corridor or Lobby where the escape route was provided with cross
00:23:52 escape route was provided with cross ventilation no Forrest's in the corridor yep that's correct so a single internal staircase with an internal lobby so nothing is connected to an outer wall
00:24:03 nothing is connected to an outer wall yes which is what we see in this Court exactly so it's all internal that's the really important point in it's all inside the tower and then there's also the limit on how far you can walk to
00:24:14 the limit on how far you can walk to reach that internal users so and that's the second point for such stage to escape routes travel distances of up to 15 meters are permitted between the flat
00:24:26 15 meters are permitted between the flat entrance door on the stair case entrance - that's correct thank you it but sorry it's probably worth pointing out that distance is also unique to CP 3 1971 so it's another
00:24:38 unique to CP 3 1971 so it's another indicator if you will yes yes and it's on that basis because we don't know for sure do it but you've deduced looking at
00:24:49 sure do it but you've deduced looking at this yeah because we haven't seen a kind of definitive document that says it was designed to CPC 71 but you've looked at the design and you think that that's the
00:25:00 the design and you think that that's the key indicator that suggests that it was CP 371 yeah that's correct I have no paperwork or anything of said either way so by a process of elimination and looking at the building as as it exists
00:25:11 looking at the building as as it exists that's how I've derived CP 3 1971 from means of escape yes thank you and do you think it might have been likely that CP 3 1971 would have been
00:25:22 likely that CP 3 1971 would have been available to designers prior to it being first published in 1971 do you think it's possible that the design guidance may have been circulating and therefore being able to be used in the design of
00:25:34 being able to be used in the design of grandfa tower earlier yes so obviously I wasn't around ahem but I think actually I if you look at the 1962 guide it actually lists out
00:25:46 at the 1962 guide it actually lists out all the people on the committee and you'll see that some very senior people from the statutory bodies in London sat on that committee so I'm going to use word I can only imagine therefore that
00:25:59 word I can only imagine therefore that in London at that time it was clear there was work being done to the 1962 version and there was a lot of work going on to bring this kind of state-of-the-art guidance into the
00:26:10 state-of-the-art guidance into the public domain so I have to assume it was understood known about and discussed at the time but I don't have any paperwork that tells me either way yes but based
00:26:22 that tells me either way yes but based on my own professional experience now and over the last 20 years those British standards those codes of practice tend to be in circulation for some time before the formal publication date
00:26:37 before the formal publication date and you've also made clear that the section 20 DLC code of practice would have also applied specifically in terms of firefighting provision in the stairs is that correct that's correct and
00:26:49 is that correct that's correct and you've identified three key differences between the CP 3 1971 guidance and the DLC section 20 code guidance in your report yeah and you've carried out that
00:27:02 report yeah and you've carried out that comparison exercise in in appendix page I just want to summarize what those key three difference yeah so the first is ventilation of the stair lobbies the GLC
00:27:13 ventilation of the stair lobbies the GLC section 20 code required a permanent vent at the head of the stairs of a greater square meter age than CP 3 1971 as their act the second key difference is about fire
00:27:25 the second key difference is about fire resistance of the staircase you say that the DLC section 20 code required the staircase lobby and lifts to have a standard of fire resistance twice that of the constructional bylaws which CP 3
00:27:39 of the constructional bylaws which CP 3 1971 adopted yeah so that's correct because for a tall building section 20 placed additional fire safety protection it wasn't meant to replace or interfere
00:27:51 it wasn't meant to replace or interfere it was additional so it made clear where it was additional to the bylaws and so to the means of escape and guidance - yes and and you think that in fact the
00:28:03 yes and and you think that in fact the stairs were designed to achieve that higher section 20 standard that higher standard of fire resistance is that correct yes based on the concrete depth as I've observed on the plans yes yes so
00:28:16 as I've observed on the plans yes yes so you think that's in all probability what the designers must have agreed with the relevant building yes yes I do I think they would have been required to do that yes because it's a section 20 building yes and you've also concluded that the
00:28:28 yes and you've also concluded that the the section 20 code permits something called a Class A for entrance and stair doors which can achieve a lower fire integrity than the 30 minutes for type 2
00:28:40 integrity than the 30 minutes for type 2 doors required by the CP 3 1971 is that career
00:28:43 career so now we're going to come in detail to that and the second day of your evidence I'll take you back to the anything and it's correct that if section 20 refers
00:28:54 it's correct that if section 20 refers to the bylaws on the matter of doors yes so there's no conflict between the bylaws and section 20 currently between
00:29:05 bylaws and section 20 currently between CP 370 exactly and the section 20 exactly so if you were docked CP 3 1971 for your means of escape design now you have to think about the intersection
00:29:16 have to think about the intersection with the bylaws - section 20 yes okay so I think what you're saying is we could
00:29:28 I think what you're saying is we could have had a situation where different codes applied to different bits of the building here I mean predominantly you think it's CP 3 1971 but there's a section 20 element as well yeah I think
00:29:40 section 20 element as well yeah I think I think section 20 and the bylaws are very complementary but the means of escape which was dealt with by the CP 3 guidance that that's where I just say
00:29:53 guidance that that's where I just say intersection is for now so when we talk about doors later I can explain that some better yep so that's 1970 Graham Fatah was built so that's why you put Omni looked at CP 319 mm
00:30:06 Omni looked at CP 319 mm you've then looked as well as looking at that at current statutory guidance made pursuant to the Building Regulations 2010 those regulations having been made under the Building Act 1984 as contained
00:30:19 under the Building Act 1984 as contained in the prescriptive document which is approved document b fire safety vol 2 in a statutory guidance document yes - Dean yeah I don't agree with the word
00:30:30 yeah I don't agree with the word prescriptive I don't know if I know okay sorry I'm not being rude yes the statutory guidance document approved talking at me and for shorthand you
00:30:41 talking at me and for shorthand you often refer to that as ADB in your report so when we've got a DB it's approved document b yep that's what we're talking about yeah and at the time of the original
00:30:52 and at the time of the original application for this refurbishment when it was made and resubmitted in August and October 2012 the Building Regulations 2010 were in force that's for a direction
00:31:03 for a direction and do you agree that the building regulations 2010 only apply to certain defined building work including where there is a material alteration which has a very specific definite definition
00:31:15 a very specific definite definition within the building regulations yes I do and in particular time qualification with some yes with some qualifications that I'll get on to okay they're my own
00:31:26 that I'll get on to okay they're my own work yeah but yes I do yeah in particular there's a non worsening principle which means that the work should be no more unsatisfactory in relation to certain requirements in
00:31:37 relation to certain requirements in schedule 1 to the building regulations then before the work was carried out is that right yes that's correct if you do work on an existing building and you have a duty to understand of the
00:31:49 have a duty to understand of the existing building is compliant or not and then your new works retains its data so if it is compliant when you start your works your work should make up no
00:32:00 your works your work should make up no worse if it's not compliant when you start your works cannot make it any more unsatisfactory is the word yep and that's a point that you have expressly
00:32:11 that's a point that you have expressly referred to in a number of places in your yes honey early stages and in section 3 you've expressly stated that you will investigate if the non-compliance is which you've currently
00:32:22 non-compliance is which you've currently identified resulted in the building being a less satisfactory than it was before the work was carried out at phase 2 of your work is that right that's correct and is it right that at this
00:32:33 correct and is it right that at this stage what you've done is look at each separate aspect of granville tower in terms of the active and passive fire safety systems and you've analyzed compliance looking at each in isolation
00:32:44 compliance looking at each in isolation exactly I've looked at every each active and passive measure on its own as a separate entity and I've not carried out any overall assessment of the intrinsic
00:32:57 any overall assessment of the intrinsic risk that may or may not have remained when those works are completed yes that's clear thank you you've also recognized in your report
00:33:09 you've also recognized in your report and this is expressly there that there may be alternative routes to compliance with the building regulations as are permitted under for example paragraph naught point to one of a dB that's
00:33:20 naught point to one of a dB that's correct the statutory guidance document makes clear that alternative routes to compliance are also satisfactory and is it your intention to investigate what if any alternative compliance approaches
00:33:33 any alternative compliance approaches were in fact adopted at phase two yeah I've been aware of that concept throughout my work for phase one and in phase two I will be very explicit and
00:33:44 phase two I will be very explicit and you know there's a lot more work to be done about where I think something was either deliberately or I'd say accidentally put forward as an alternative compliance route and you've
00:33:57 alternative compliance route and you've also not considered industry practice at this stage phase one is that correct yeah that's correct and I I hope when I wrote that I was thinking mostly about the cladding because of various
00:34:11 the cladding because of various publications that occurred in the years before and during the primary refurbishment and I will deal with that as part of the culture of compliance
00:34:23 as part of the culture of compliance work I intend to do and phase two and is it right that you will be giving a final view on compliance of the building works carried out over time at Grenville tower with the applicable regime in your phase
00:34:36 with the applicable regime in your phase two but that's correct now just pausing there an overall can you explain why at this first stage of your work you've looked at effectively
00:34:48 your work you've looked at effectively the design guidance at the time of construction cp3 1971 and the current design guidance in a DB the statutory design guidance in that document yeah I was trying to be
00:35:00 that document yeah I was trying to be very transparent so not trying to impose say standards now on something that may or may not have been worked on during say particularly the primary Irishman so I wanted to be very clear
00:35:13 Irishman so I wanted to be very clear about then and now as clear as possible I thought it was fair and that's why I took that approach for now once I enter
00:35:24 took that approach for now once I enter into the domain of comparing compliance and non-compliance and contemplating material alteration or knots it becomes complex and the judgment will also be
00:35:36 complex and the judgment will also be required so for now I want you to keep it factual and separate and keep that until we get into other matters I want
00:35:51 until we get into other matters I want to move on now and I want to start substantively really by looking at the composition of the external envelope at gruntal tower now both you and professor Bisbee spent a considerable amount of
00:36:03 Bisbee spent a considerable amount of time in your oral presentations back in June explaining how the exterior of Graham fatale was configured both before and after the major refurbishment works we're not going to repeat all the detail
00:36:14 we're not going to repeat all the detail of that here yeah in addressing the external envelope today I want to concentrate on the extent to which the exterior of the building was able to resist the spread of fire and what
00:36:25 resist the spread of fire and what features of that exterior exterior envelope you think were the most significant in terms of the events of the 14th of June mr. chairman I'm going to give a trigger warning now because
00:36:37 to give a trigger warning now because later in this section we are going to be look at looking at some photographs of their the burnt out tower including some photographs of windows before and after the fire which some may find distressing
00:36:50 the fire which some may find distressing much later this morning it will be after the break we'll also look and it may even be this afternoon at the flame spread one of the flames spread videos so I just give that warning now in case anyone wishes to take are we going to
00:37:03 anyone wishes to take are we going to get to those very soon we're going to get to some pictures of windows fairly quickly or and the video comes later and I'll warn again thank you so I want to
00:37:15 I'll warn again thank you so I want to start by picking matters up but chapters 8 to 10 of your report and considering your evidence about the construction of the X
00:37:22 the X envelope including the window openings and then the roots for fire spread both out through the window openings and then vertically and horizontally through the building envelope before we get into the
00:37:35 building envelope before we get into the detail does your conclusion remain that that as you've set out at paragraph two point nine point nine of your report that there were multiple catastrophic
00:37:46 that there were multiple catastrophic fire rates created by the construction form and construction detailing that was used does that still your overall conclusions that is my overall conclusion now taking the window
00:37:57 conclusion now taking the window openings first I just want to work through that some of the key points that you make so you can explain them as you explained in chapter 8 of your report the design of the windows was pushed
00:38:08 the design of the windows was pushed outwards during a refurbishment that's correct isn't it that's correct now one of the consequences of that is it brought into the external wall construction a horizontal void which had
00:38:20 construction a horizontal void which had previously been on the exterior in the form of a sloping lip beneath the window I want to take you to a figure just to have a look at okay coach yes if we go to figure eight point six that's B la s
00:38:35 that's it it's a possible sorry excuse me it's a possible for the screen to come nearer I seem to have developed eyesight problems in over an eye so when I break something if I move us I think
00:38:50 I break something if I move us I think what you may find is we can blow it up on the speaker oh yes for drawings that's very hard to make see but I can look at my own watch I just look at my own what I'd like to do is blow up well he's not better director we can actually blow up the yeah let's blow it up like
00:39:02 blow up the yeah let's blow it up like that to start with just so that we know is that does that a comfortable size for you if not we can move the screen yeah I just wouldn't mind it a bit nearer sorry
00:39:13 just wouldn't mind it a bit nearer sorry just for drawings it's quite difficult to see the data I'm sure
00:39:20 yeah thank you very much yeah this section here is effectively showing
00:39:32 section here is effectively showing sorry master final lovely thank you very much sorry about that okay so here what we have is the original conditions on
00:39:44 we have is the original conditions on the left and then the refurbished conditions on the right is that correct that's correct and and you've shown me clearly the way the window is being pushed out yes I just want to focus we'll take this each in stages at the
00:39:57 we'll take this each in stages at the moment on if we go can we zoom in on the right hand image and I'm looking at the
00:40:08 right hand image and I'm looking at the bottom of the window the little lip and you've highlighted in yellow and hatched black a little space there that's correct and that's a horizontal void and that's because of the original cutaway
00:40:21 that's because of the original cutaway of the concrete exactly in the original design of Granville Tower so when the windows go out that suddenly becomes a horizontal voyage yeah is that correct is that's correct
00:40:38 and then on the sides of the windows abutting the columns the pushing out of the windows also resulted in a vertical gap down the side of the windows which
00:40:49 gap down the side of the windows which is formed by a groove in the original concrete exterior of the columns again let's look at we'll look at figures to support all of these points and we looked at this with professor business yesterday can we look at that gap let's
00:41:01 yesterday can we look at that gap let's start with figure 9.8 VLA s60 is nine at page 12 and if we can blow up figure
00:41:23 page 12 and if we can blow up figure nine point eight it is it right that what we see there so the original concrete columns have these little cutaways to them and they kind of be
00:41:35 cutaways to them and they kind of be called them it's kind of biscuits to start with so there's little grooves there and then there's a larger groove between the the old span drop the existing spanger along the column here
00:41:47 existing spanger along the column here of martyred red so there's two types of grooves so by pushing out the window then incorporated that gap into the side
00:41:58 then incorporated that gap into the side of your window where it abuts the column exactly that all becomes part of the internal side of the new external wall yes and there's a good photo of that in
00:42:09 yes and there's a good photo of that in terms of the as-built construction if we can go to figures nine point nine and nine point 10 be la s60 is nine on page 13 yeah perhaps if we can focus to start
00:42:21 13 yeah perhaps if we can focus to start with on figure do you want to focus in can you see it clearly enough yeah that's fine yeah so in the top photo yeah we can see that gap very clearly down the side of the window looking
00:42:34 down the side of the window looking downwards and which is the insider which is the answer oh sorry so there there's the the window there's the membrane and this is this is the the inside here yes
00:42:48 this is this is the the inside here yes just to everything's been stripped away yeah in this particular photo yeah and you can see the de groove the going down between the two pieces of concrete there and if we can look at the bottom figure
00:43:01 and if we can look at the bottom figure figure 9.10 yeah we can see there that someone's made an attempt to fill that with expanding very correct correct yeah and I think professor Bisbee said
00:43:12 and I think professor Bisbee said yesterday some areas seem to have foam in it and some do not is that consistent with your site inspections yes it is so there's a variation about whether that has any kind of yeah if it's permanent if it's
00:43:25 kind of yeah if it's permanent if it's been done or not yep that's correct yep and you also know that the windows themselves were reduced in size leaving a gap of between 30 and 120 millimeters
00:43:38 a gap of between 30 and 120 millimeters between the sides of the windows and the adjacent columns is that correct yeah again let's look at a figure on that so
00:43:49 again let's look at a figure on that so let's go to figure eight point 15 B la s6 series 8 page 17 yeah
00:44:15 if we can go to the photograph at the top left photograph and zoom in on that photograph yeah okay sorry I think this is quite an important point so the
00:44:26 is quite an important point so the drawings that the Harley drawing and we can maybe show that later had a little note on it saying that those works the
00:44:37 note on it saying that those works the window works needed to take into account that because the columns weren't perfectly plumb there was a you know a variation you call it so anything between 30 and I think well I can't
00:44:52 between 30 and I think well I can't remember the exact numbers and so I'm a bit nervous so it was 32 I think it was 120 on the drawing I would just need to look at us and so it meant that there
00:45:03 look at us and so it meant that there isn't a fixed width that's been designed it changes as a function of the conditions one would find in that flats and on site I measured that in different
00:45:14 and on site I measured that in different places as either 20 or anything up to a hundred and thirty millimeters and that's a very very important to understand about that column condition that depending on where you are in the
00:45:27 that depending on where you are in the building the window either have to be closed or have to be up to a hundred and thirty millimeters away from that column as you understand it was an inevitable
00:45:41 as you understand it was an inevitable part of the design was that the window there should be a gap because the windows were Narrows and the space available so the windows being narrower is one point but there it this is this
00:45:54 is one point but there it this is this is to do with it's called construction tolerances so something isn't absolutely perfect on sites you know you have to move things it's meant to be a very slight movement and but I think that
00:46:05 slight movement and but I think that drawing is very important because it shows that that was the the scale of tolerance they were dealing with so it's two points the window size and then the
00:46:16 two points the window size and then the plumbness of the columns and so dealing with that during construction yes thank you yes we think he might be figure eight point thirteen that's be a layer six zeros eight
00:46:27 six zeros eight page 15 oh yeah yeah is that the right one yeah hopefully you can see the note
00:46:37 yeah if we can blow up I think it's the right hand bigger thank you yeah you should but if you look up 35 the number
00:46:53 should but if you look up 35 the number 35 here there's a little arrow over to a note it's hidden here in my report there's a proper reference and someone can check for themselves and so that you
00:47:04 can check for themselves and so that you can see that variation you see the two red lines so that was a designed for variation yep but what it means in terms of my interest in US is to do with fire
00:47:19 of my interest in US is to do with fire and its interaction with that gap thank you
00:47:28 now that gap was filled with a number of materials is that correct that's correct it's filled with an e DPM rubber membrane and that was is it right that
00:47:40 membrane and that was is it right that that was bonded to the window frame and to the face of the concrete column on-site yeah I don't know how it was bonded but it should be bonded and it
00:47:51 bonded but it should be bonded and it forms a membrane and fills the gap yes and in your view is that material particularly prone to promoting flame spread particularly prone I I would just
00:48:02 spread particularly prone I I would just say it's combustible yeah if that's okay yeah it's made it it's made of rubber yes I I don't know what you mean by particularly prone in the car sorry I'm probably getting really pedantic content
00:48:13 probably getting really pedantic content context with wash so it's combustible yeah thank you since we're being pedantic when you say the film when you're asked to agree that the film fills the gap would it be more accurate
00:48:25 fills the gap would it be more accurate to say it covers the gap yes exactly so it it to me it's it covers over it's like putting a piece of paper over something you you just cover it over
00:48:38 something you you just cover it over like wallpaper and they must have bonded at somehow and it's a damp roof membrane yeah it's not damp getting into the window exactly it's meant to stop that kind of ingress yes you've said in
00:48:52 kind of ingress yes you've said in Section ten point three point 11 of your report that it's a combustible synthetic rubber material that ignites between 180 degrees C and 378 degrees C can we just
00:49:03 degrees C and 378 degrees C can we just have a look at that yeah that's elas five zeros ten at page 11
00:49:15 I think it goes into the next actually good yes the next page first of all synthetic rubber material which Knights killed over to the next page sorry that's my I'd like unlike all
00:49:30 page sorry that's my I'd like unlike all materials it's changing state before ignition
00:49:35 ignition it isn't in a cold state and then it ignites its changing states yeah and and you've got that temperature range 183 seven eight you've obviously got it from
00:49:46 seven eight you've obviously got it from this in ignition here book yeah and that's quite a big range I mean do we know any more about that material at this stage no that's not something I have gone into detail beyond I prefer my
00:49:58 have gone into detail beyond I prefer my own work I'm just interested and if something is combustible or not yes other experts are getting into the absolute fine detail millimeter by millimeter degree by degree yes on part
00:50:10 millimeter degree by degree yes on part all those materials do yes thank you and there's it right there for that the edpm membrane led directly into the column cladding cavity and onto the insulation
00:50:22 cladding cavity and onto the insulation that was behind the rain screen panels on the column again we're going to look at some figures on that yeah exactly so so in behind the uPVC reveal so the covering you have the the old window
00:50:37 covering you have the the old window reveal covering and you have some additional insulation that's marked on the drawing as being required and and then you also then have the EPDM and I
00:50:48 then you also then have the EPDM and I wonder if we could like even go back to say figure nine point nine or just look at the side of the window yeah or even figure eight point thirteen where all
00:51:00 figure eight point thirteen where all the materials are marked up maybe figure eight point thirteen 8.13 youngbae la s60 is eight page 15 yeah I think that's
00:51:11 s60 is eight page 15 yeah I think that's a the clearest way of trying to show it so do you want to just do attention - yeah so
00:51:19 yeah so so it's marked you've your uPVC and i thought you've your uPVC and professor
00:51:30 thought you've your uPVC and professor trailer was very eloquent about how that loses its mechanical stiffness quite quite a note relatively low temperature and then in behind here is what's very important and it says for example
00:51:42 important and it says for example insulation by others it says to retain about the green up on the top there it says to retain the original existing
00:51:53 says to retain the original existing frame remains yellow silence removed by others when necessary yeah and I think actually this is a very important drawing so you've got that information and then you've got the little note telling you that it's
00:52:04 little note telling you that it's anything from 35 up to 290 millimeters so when you think then about the location of the uPVC because that has to line up with the window frame there's
00:52:16 line up with the window frame there's either a small or actually quite a large gap when you think about it behind us so that means then the length of the EPDM is a feature of this gap that's trying
00:52:28 is a feature of this gap that's trying to film okay yeah and once the uPVC is gone and from what I know the insulation
00:52:39 gone and from what I know the insulation layer was glued onto the back of the uPVC we're coming to that oh sorry that's okay you can see what you're going yeah sorry it's good let's just just with the edpm membrane can we just
00:52:50 just with the edpm membrane can we just look a couple of pictures of that in its on-site configuration let's go to figure eight point two to be la s60 eight at page 22 and if we can just zoom in on ya
00:53:04 page 22 and if we can just zoom in on ya figure so there I think what we're seeing is the the range screen has been removed both on the spandrels below the window yeah and on the column and what
00:53:16 window yeah and on the column and what we're seeing there right down the middle is the column insulation is that correct that's correct and then to the left of that again we'll come back to the exposed face as the insulation let's not worry about those for the moment we see
00:53:27 worry about those for the moment we see that black edpm weatherproof membrane is that correct that's correct so there we can see it yeah going into the column effectively yeah that's covering up yeah
00:53:38 effectively yeah that's covering up yeah can we also look at another figure on that figure eight point two three on the next page page 23 and there what you've
00:53:51 next page page 23 and there what you've shown in blue is what it would look like from the inside of the flat yes where we've got the column I think this is yeah this is flat 13 which is on level 4 it's the kind of exemplar flat across
00:54:03 it's the kind of exemplar flat across the hallway from flat 16 so this is what the flat 16 window would have looked like is that correct exactly and it's quite striking on site because you
00:54:14 quite striking on site because you realize you could literally cut a hole and in the EPDM and put your hand into the column cavity now we touched on it a
00:54:28 the column cavity now we touched on it a moment ago that gap on both sides of the window behind the uPVC and this is Bay's at the head and base of the window and down the sides was insulated yes we
00:54:40 down the sides was insulated yes we found two products on site is that right yeah as a Celotex TB 4000 or king spans them a pitch TP 10 is that correct yes that's correct again can we just see a picture of that that's B la s6 zeroes 8
00:54:53 picture of that that's B la s6 zeroes 8 at page 19 figure 8 point 18 if we can zoom in on that so again here is it
00:55:06 zoom in on that so again here is it right we can see the uPVC has deformed and melted and and yes / yes and then above that you're drawing attention in the orange bubble you know to the
00:55:17 the orange bubble you know to the combustible insulation is that correct yeah I'm drawing attention to the Reg logo and that Celotex it appears to be 4,000 years correct it's a red it does
00:55:31 4,000 years correct it's a red it does to be absolutely precise it's a red logo and at that thickness seems to be the tbh 4,000 and it's 25 millimeters right
00:55:43 tbh 4,000 and it's 25 millimeters right yeah so that's a different insulation product to the product that we see when we get to the spandrel insulation in the column insulation on the outside
00:55:54 column insulation on the outside exactly there are small pieces of insulation around each side of the window trying to fill up the gaps that were formed between the old and the new
00:56:05 were formed between the old and the new windows and just to be absolutely clear they're at the top and the bottom and at the sides that's correct so they are marked on the drawings as being required on the top on the bottom on the two sides and I have personally seen them on
00:56:18 sides and I have personally seen them on the top on the bottom and on the AL you glaze side as well as on the column sides III didn't see the insulation
00:56:29 sides III didn't see the insulation myself on a column side and I have to rely on the drawing there yeah yep let's have another look at another drawing elas six zeros nine at page 20 that's
00:56:40 elas six zeros nine at page 20 that's bigger 9.13 so that's again another another picture where we can see it on the left the insulation that you're
00:56:51 the left the insulation that you're talking about behind the uPVC yep yep
00:56:58 and you've asked for test data for the Celotex TV 4000 but that's not been provided to date is that correct not yet no thank you and you say that the
00:57:11 no thank you and you say that the publicly available beat BBA that's the British border bagramon certificate says that has no determined performance or as European class F is that correct that's
00:57:22 European class F is that correct that's correct whereas that should have been of limited combust ability is that correct that that's a complex question sorry
00:57:36 that that's a complex question sorry because it's where its window insulation yeah and so yes I think as a minimum it should have been limited combustibility it's probably worth stating that I
00:57:48 it's probably worth stating that I couldn't today look up something an approved document b to see if window insulation and wall insulation are are meant to be different
00:57:59 meant to be different can we just I think this is a good point just to clarify about the European classification system because I'm going to comment some of my later questioning to ask you more questions about is this
00:58:11 to ask you more questions about is this class II or Class D acceptor so I think it's just worth in just in general and general terms I know this is a very complex topic that you've dealt with in appendix F and you will have to get into more detail on this at Phase two but
00:58:22 more detail on this at Phase two but yeah in general terms is it right that the European classification system has a sliding scale of classifications with seven different classes of reaction to fire that's correct
00:58:33 fire that's correct where we have a 1 a 2 and then B through 2 F that's correct and is it right that kind of when you get down to PMF we're talking really bernie is that I couldn't
00:58:45 talking really bernie is that I couldn't use the phrase really bad I'm very sorry that's it I just dreadful act as an expert if I start saying really burn David Germany sorry I'm gonna throw on a more serious
00:58:59 sorry I'm gonna throw on a more serious no sorry so a1 is meant to be non-combustible a2 is limited combust ability and then from B down there's greater degrees of flame and heat
00:59:12 greater degrees of flame and heat observed or allowed in the test yes I'm gonna talk professor Bisbee in it because that's how he first explained to me and is it right that when these
00:59:24 me and is it right that when these European standards were adopted that where you've just explained it but let's just be clear the way the national guidance specified non combustible materials the use of a1 materials was
00:59:35 materials the use of a1 materials was considered acceptable and where the national guidance specified limited combust ability the use of a2 was considered acceptable is that correct I know yes it is I know what you mean yes
00:59:46 know yes it is I know what you mean yes it is yeah but there are two different things national in Europe they are there had to be some kind of harmonization even though they're not testing the same thing is that correct so again I'd I
00:59:58 thing is that correct so again I'd I couldn't say that there was harmonization so in approved document b at the back in table a 6 and table a 7 it lists out a 1 or a 2 as is
01:00:09 it lists out a 1 or a 2 as is appropriate yes thank you do you want to go to the table that we see in the Sen one three five oh one that lists out the
01:00:20 one three five oh one that lists out the European yes do you think that would be hell I think it would be helpful because it's the clearest table then yeah about all the different tests you need to do to get that letter I won't be able to
01:00:33 to get that letter I won't be able to keep repeating them endlessly it's very hard to remember them actually there's so many yeah so be good to see that table please great yeah so I think it's a pendeks F figure F 4 yeah that's it if we zoom in
01:00:45 figure F 4 yeah that's it if we zoom in on that figure yep so you've taken this table yeah from BS en 1 3 5 0 1 1 table 1 is that correct that's correct and
01:00:56 1 is that correct that's correct and this gives us the classifications a1 down to a correct and it's a take very clearly the activity required and so the relevant
01:01:07 activity required and so the relevant test evidence required for each classification and that's what I've looked for when a party has submitted test evidence to the enquiry yep now in
01:01:19 test evidence to the enquiry yep now in in a later section of my questioning we're going to look at each product and I'm going to ask him what the classification is I want to stick at the moment with Windows yep so that we've looked at the Celotex TB 4000 which you
01:01:34 looked at the Celotex TB 4000 which you say has class F yeah and a material of limited combust ability is a two are higher or better yeah and then the kingspan firmer pitch TP 10 is Cass E is
01:01:47 kingspan firmer pitch TP 10 is Cass E is that correct that's correct and you actually believe that that kingspan Therma pitch TP 10 was originally specified to be used as the insert
01:01:58 specified to be used as the insert around the extractor fan in the windows is that correct you can say that in your reports oh yeah oh yes that was yes so probably it's worth saying that the window insulation
01:02:10 worth saying that the window insulation isn't specified that the products or it's not written down and the papers that I have at this stage so in the design droids you've seen that far you
01:02:21 design droids you've seen that far you can't see any specification for what that window installation was supposed to be exactly the uPVC windows surround yes and we've discussed those a lot this
01:02:35 and we've discussed those a lot this week but can we just look at a picture go to the la s6 zeros 8 at page 16 figure eight point one four
01:02:57 figure 8.10 8.14 yeah yes sir just to orientate ourselves back on the uPVC new PVC windows surrounds yeah and
01:03:10 uPVC new PVC windows surrounds yeah and we again we've had a lot of evidence about these windows effectively become liquid between 75 and 100 degrees C and you also make the point they release toxic hydrogen chloride gas yeah sorry
01:03:23 toxic hydrogen chloride gas yeah sorry yeah yeah no understood yeah they change yeah they can't stay tacky and in for example professor Bisbee's presentation
01:03:35 example professor Bisbee's presentation earlier on in june he said the typical day to day after service temperature limits for them were about in the range of 50 degrees Celsius and it's melting temperatures between 75 and 105 degrees
01:03:46 temperatures between 75 and 105 degrees Celsius that's correct that's consistent with I think yeah exactly yep now from a fire engineering perspective given their low melting
01:03:58 perspective given their low melting temperatures do you have a view about the choice to use uPVC around the windows surround is that something you feel you can express an opinion on at this stage as a from a fire engineering
01:04:10 this stage as a from a fire engineering prospect yes is there anything particular you want to draw attention to in terms of the use of uPVC in the windows okay well I suppose I wouldn't I suppose for me I wouldn't
01:04:21 I wouldn't I suppose for me I wouldn't be if I was asked to look at a drawing say on another building I wouldn't be particularly cognizant Abady uPVC would be more about what's going on behind it which were coming to yeah yeah and just
01:04:35 which were coming to yeah yeah and just to be clear in the event the uPVC was glued to the insulation behind that's correct isn't it yes it appears to be the case I have some photos of my report showing the glue line yeah there's a
01:04:47 showing the glue line yeah there's a good one in professor Toreros report perhaps we can just go to that that's figure 55 JT OS you know page 42 and you know he drew attention to the squiggle of glue along the side is that correct
01:05:00 of glue along the side is that correct yes yes booyah did you see any in any of your investigations any mechanical fixings ever no I didn't see any Beyonce's yeah do you think that the presence of
01:05:11 you think that the presence of mechanical fixings could have potentially had an impact on the propensity of that uPVC to come away fall away to form with my mechanical
01:05:23 fall away to form with my mechanical fixings that potentially made a difference yeah I think it's for any of those materials you PVC or say compass of panels to when they're free you know
01:05:35 of panels to when they're free you know free to move or just fixed very lightly when this you know they're losing their structural stiffness and they're changing states I think that they can fall away or you know move more when
01:05:49 fall away or you know move more when they're not mechanically fixed I think appendix F and approved document b provides some very interesting information about the impact of
01:06:00 information about the impact of mechanically fixing it's in the context of a panel but i think it's relevant to uPVC because it changes state like that as well yeah you've also identified the
01:06:12 as well yeah you've also identified the fact and again you touched on this earlier that the original window surrounds which were not removed contained other combustible materials let's just list those so we had the original wooden sills yeah and the
01:06:23 original wooden sills yeah and the internal wood lining they remained in place they seem to have been left there yes yeah can we just have a quick look at that that's yes six zeros eight page 24 forget 8.25 so in the bottom figure
01:06:39 24 forget 8.25 so in the bottom figure oh yeah see a good illustration of that is that what we see the wooden frames so there that's the supporting frame you know just so here in here they're the
01:06:52 know just so here in here they're the supporting frame and in other places the actual Timbers for the sill and the reveals are also present so just in this particular photo it's just the supports for the cell and the
01:07:05 just the supports for the cell and the supports for the reveal the old wooden lining yes and you could you I have photos and appended see where you can see both
01:07:14 see both yep and it's good to just always refer back to this drawing in my report figure eight point 11 where it's drawn on that the the sills the reveals and the
01:07:27 the the sills the reveals and the support and frame are to be yes let us bring that up no no it's okay just just to make up yeah and then we also had something you identified as pearl board
01:07:39 something you identified as pearl board yeah above and below the windows is that correct yeah and is it right that's a layer of plaster board with a combustible backing double layer product yeah that's correct
01:07:51 double layer product yeah that's correct let's have a look at that if we look at BL a s60 is a two-page sixteen figure eight point one four
01:08:05 and you have marked that the original per board ceiling Phyllis trip above the wind oh yes that's correct yeah and you
01:08:16 wind oh yes that's correct yeah and you say in your report that this is a combustible material with an ignition temperature of 271 degrees yes and in pure form yeah and just to clarify you also say there's Perl board underneath the window is that correct yeah and is
01:08:29 the window is that correct yeah and is that in a kind of a larger quantity there under the window it's like a lining or underneath the window yeah all the way along I yes so it's much larger
01:08:40 the way along I yes so it's much larger underneath it's a traditional form of insult insulation or room yeah and you've identified a number of pathways
01:08:51 you've identified a number of pathways between the outside and the inside in Section nine point three of your report pathways for the potential spread of fire yeah I'm not going to go to every single one of those because there's a number of those are kind of
01:09:02 there's a number of those are kind of theoretical pathways but your conclusions are at paragraph nine point seven I just want to ask you about those does it remain your position that once there was a localized fire near the
01:09:14 there was a localized fire near the window the majority of the materials around the window had no potential fire resisting performance that's correct and therefore no part of the construction had the ability to prevent
01:09:25 construction had the ability to prevent fire spread from inside the building to the external wall cavity is that correct that's correct and once there was a fire in a flat anywhere near a window there was a very high likelihood that it would
01:09:36 was a very high likelihood that it would break out of the flat and into the cladding that's correct that's your view
01:09:45 mr. chairman I'm going to go to another topic now which is about cavity barriers around the windows and I want to spend a little bit of time on that so I wonder whether I know people have been asking if they can have slightly more frequent
01:09:57 if they can have slightly more frequent breaks and I think I have the time to accommodate that so it would now be an appropriate moment for a ten-minute break
01:10:03 break I think it probably would yeah Cory welcome a break wouldn't you I would love a little tiny break yes well we'll have a break now I'm gonna say quarter past eleven that's slightly longer than
01:10:14 past eleven that's slightly longer than ten minutes but it's easier to work with Peter on the clock again to ask you please not to talk to anyone about your evidence up in your out of the room and you gave the usher will be back at 1:15
01:10:25 you gave the usher will be back at 1:15 right thanks come on
01:10:37 right 11:15
01:20:27 yeah
01:20:38 can you take your seats please and remain silent thank you
01:21:55 right on clean ready to carry on yes thank you yes was great so sticking with the windows for the moment and stepping back and considering that window arrangement as a whole and just leaving
01:22:07 arrangement as a whole and just leaving aside the combust ability of the materials for the mainland would you have expected to see some form of fire resisting cavity barriers around the windows yes I would now I quite like you
01:22:19 windows yes I would now I quite like you to explain to us what the regulator requirement was a relation to cavity barriers and what I'd quite like to do is take you to a couple of sections of a pre dog Herbie okay these in the
01:22:31 pre dog Herbie okay these in the diagrams just for you to explain to us what the requirement was yes so can we go to CLG five zeros two to four at page
01:22:42 go to CLG five zeros two to four at page 82 to start with and can we blow up this is diagram 33 is that that that's the correct diagram to start with yes yes please yeah so if you can blow that up
01:22:54 please yeah so if you can blow that up that's great so by reference to this diagram can you just explain to us what the requirement is for cavity barriers in relation to the windows we'll come back to this diagram later when we look
01:23:07 back to this diagram later when we look at cavity barriers in the external wall proper okay so in this diagram it shows that the where the openings are made for
01:23:18 that the where the openings are made for a window and that opening must be sealed on all sides to seal up the cavity made
01:23:29 on all sides to seal up the cavity made by the construction of the wall you've got the you know the external face an internal face of the wall and fire resisting construction is placed the top
01:23:42 resisting construction is placed the top and bottom of the wall and also you see all the sides as needed yeah I think we're about to blow that section out that's that's a good idea yeah so in
01:23:53 that's that's a good idea yeah so in gray it's kind of hard to see those little grey squares indicate a cavity barrier is required to seal the cavity look
01:24:01 look from the two parts of the wall outside on inside of the wall a cavity is formed and you seal at the top where you've caught an opening in the wall for the
01:24:12 caught an opening in the wall for the window and so yeah yeah do you want to look at 9.3 as well of a DB about
01:24:24 look at 9.3 as well of a DB about junctions and cavity closures it would that be helpful that's on the next page page 81 yeah so for I mean I can do that from here okay so where a compartment floor meets the external wall within the
01:24:39 floor meets the external wall within the cavity there oh yeah within the cavity there Ora
01:24:50 okay so just yeah oh yeah so here's the compartment floor aunt where where it meets the external wall within that
01:25:03 meets the external wall within that cavity a cavity barrier is required there's an additional item where the internal phase of the wall meets the floor they're called fire stops they're different performance and the
01:25:15 different performance and the significance of having the cavity barrier at the floor and at the window opening is from this compartment to the next compartment you have two cavity
01:25:28 next compartment you have two cavity barriers sealing that cavity between those two compartment floors so one at the window one of the floor another out the window and you're into the next apartment yeah
01:25:40 and you're into the next apartment yeah thank you very much yeah and in terms of cavity barriers for windows yeah they are kind of different tight to the cavity barriers that we've seen on the external wall we'll look at
01:25:52 seen on the external wall we'll look at those later are there special cavity barriers for window openings so you can buy or different types of cavity barrier
01:26:04 buy or different types of cavity barrier yep or so and I you know I I don't know a whole range of products as such but the approved document b also allows you to use some classic construction
01:26:15 to use some classic construction materials as a cavity barrier and it gives specific rules about the thickness of those materials if you want to rely on them as a cavity barrier so in terms
01:26:27 on them as a cavity barrier so in terms of the cavity barriers that were installed in Grandville tire they're made from a kind of a mineral wool substance so once you could use that substance at a thickness to give you the
01:26:40 substance at a thickness to give you the performance and the performance at a window is 30 minutes fire at 30 minutes fire resistance integrity and 15 minutes insulation so so it's about the material
01:26:54 insulation so so it's about the material type and its thickness and how you install it and depending on the product supplier they will have specific detailing requirements you just referred
01:27:06 detailing requirements you just referred them to 30 minutes for resistance integrity yeah and 15 minutes insulation can you just in very simple terms for us just explain what the difference is so
01:27:17 just explain what the difference is so integrity is is to try and stop you know fire and smoke you know kind of blocking it so blocking the products and insulation is about trying to stop the
01:27:30 insulation is about trying to stop the heat on the other side of a substance so you're blocking smoke and flame and you're trying to insulate it so if there was something above it's not getting too
01:27:41 was something above it's not getting too hot also because obviously even if the products get blocked you still have heat transfer all the time upwards so it sounds to me where evidence that they might have been a
01:27:52 evidence that they might have been a number of different options that could have been available to provide for those cavity barriers around the window openings in a window in any window opening this any event our opening there
01:28:03 opening this any event our opening there is yep and just to be clear you found no cavity barriers at the windows when you did your site inspection is that correct that's correct
01:28:16 and in this location as shown on the the statute a guidance document could they have inhibited the spread to the exterior by providing a barrier between
01:28:28 exterior by providing a barrier between the e PVC windows and the combustible components of the carrying system I
01:28:36 think because of what I can't answer that question directly because we have to remember the old window and the new
01:28:47 to remember the old window and the new window has moved and then the relative location are the cladding I don't know if you want me to try and get into that but remember the devoid around the window and then the voids into the main
01:29:00 window and then the voids into the main cladding are very complex and interconnected yep okay so in in a classic window yes you could seal off that cavity at Granville Tower it's much
01:29:14 that cavity at Granville Tower it's much more complex than that because of the interconnection of all the cavities and the location of the ACP and the relative location of the two windows so it's not
01:29:27 location of the two windows so it's not obvious it is what you're saying it's not obvious how you could have provided cavity berries with that kind of arrangement and exactly in fact I have spent a lot of time trying to work out
01:29:38 spent a lot of time trying to work out how Warren could the joy you've examined some of the drawing yep all this yes what did the drawings
01:29:51 yep all this yes what did the drawings show the presence of cavity bearing no they did not so they were never provided for David they don't appear to have been considered no well then next question
01:30:02 considered no well then next question doesn't arise okay now just moving on a little a point made in professor Toreros report is that windows can't be designed to withstand the heat of an external fire when it when you have a big
01:30:15 fire when it when you have a big external fire going on and he refers to the potential for an external fire to generate heat fluxes of up to 120 kilowatts per mega square in the light of that do you still think the
01:30:27 of that do you still think the weaknesses in the wind changement which you've identified 10 she played a role at Granville tower I I do think the windows played a role I don't quite understand the full extent
01:30:39 don't quite understand the full extent of what Professor torero means is that the glass or the frame or a bone I think it's the glass predominant older glass I agree with that yet could it have played
01:30:51 agree with that yet could it have played a role in terms of first of all facilitating the initials escape of the fire out of the compartment of origin the construction materials around the window yes yes yes it did yeah and again
01:31:02 window yes yes yes it did yeah and again we're going to come back to escape route later yes okay do you think that the weaknesses in the window arrangement that you've identified could have also accelerated the rate at which the fire
01:31:13 accelerated the rate at which the fire could break back in once it's spread up the exterior yes I do
01:31:21 and is that whether or not you're looking at vertical that fire spread or you're looking at kind of downwards fire spread melting and dripping of materials
01:31:32 spread melting and dripping of materials setting fire to subsequent fires yeah do you think those weaknesses would have played a role in both scenarios yeah so so because of the voids around the window and how those voids then
01:31:43 window and how those voids then connected into the larger cavities and all the materials in those two parts the small cavities and the much larger main cavities yes there is an easy route
01:31:55 cavities yes there is an easy route either above you know at the under spandrels above the window on the columns beside the window and also on the insulation core panel side of the
01:32:06 the insulation core panel side of the windows also where the alyou glazed panels were installed so it's about materials and just that interconnectedness of all the cavities
01:32:17 interconnectedness of all the cavities and do you think the these weaknesses I just touched on it and might be even more important when you're looking at maybe fires on ledges that have broken back down and then smaller fires are
01:32:31 back down and then smaller fires are generated from melts a melting and dripping products above and then it hits on the window ledges we saw that in professor
01:32:40 professor these evidence do you think potentially then the weaknesses in the window arrangement are relevant yeah so there it's it's a heat transfer route isn't it it's a route for it if there's a little
01:32:51 it's a route for it if there's a little fire cooling on do mean on an ACP pan exactly or outside the window yeah so if you have some kind of localized condition on the panel there remember as
01:33:02 condition on the panel there remember as I said that the so you the cavity in behind there is connected into the cavity in the window and you've got combustible materials around the window
01:33:13 combustible materials around the window I just want to ask you a few questions about spray foam professor Bisbee has identified the use of spray foam to seal gaps around the windows to provide a
01:33:25 gaps around the windows to provide a final airtight seal yeah he thinks that that might be potentially significant regarding the ingress of fire and smoke around the windows your photos and we
01:33:38 around the windows your photos and we can look at them demonstrate fire entry at windows do you have any views about the extent to which that process would have been exacerbated by spray foam
01:33:50 have been exacerbated by spray foam around the windows do so I'm assumin siddur as the spray foam used to be one of the many combustible spray phones I
01:34:03 of the many combustible spray phones I don't I don't think it exacerbated the situation in the sense I think there were plenty of other combustible materials there and that's just one more
01:34:16 materials there and that's just one more I mean if you wanted me to give you I'd kind of want to quantify or the relative quantities I can do that for next week but I don't see that as a I wouldn't
01:34:27 but I don't see that as a I wouldn't call it a dominant parameter in the context of heat transfer or a flame you know flame progression yep through the construction around the window thank you I now want to turn to look at the
01:34:40 I now want to turn to look at the pathways for smoke and fire in the external cladding arrangement and this is addressed in detail in section 10 of your
01:34:51 and I'd like to just pull up BL as50 ten page five which is your diagram of six pathways bigger ten point two and ten
01:35:02 pathways bigger ten point two and ten point three so we're going to keep coming back to this just kind of orientating ourselves on this so here you have like five different pathways and then in ten point three we'll see a
01:35:17 and then in ten point three we'll see a pathway F which will come to you last around the the crown so let's let's start with pathway a which you have as vertical spread both up and down the
01:35:29 vertical spread both up and down the height of the columns now you say in sections ten point three point one to ten point three point two four of your report
01:35:37 report that the columns contained a number of combustible materials including PIR insulation there was the core of the aluminium composite panel and then
01:35:51 aluminium composite panel and then obviously we have the edpm rubber proof membrane down the sides yep you've drawn attention to the fact that they were ventilated because of gaps between the cladding panels designed to permit
01:36:03 cladding panels designed to permit ventilation of the cavity is that correct that's correct that's in the column yes what's in the cut you're talking about we go dig out send in the the panels and attach to the column yeah
01:36:15 the panels and attach to the column yeah yeah and you say that once ignited the natural flow of air into the cavity driven by the rising hot air would provide a continuous source of oxygen fueling the fire is that correct yes so
01:36:27 fueling the fire is that correct yes so you're saying in fact they're ventilated columns is important is that right yes so they're exactly you know to try and I mean there's been an awful lot of discussion on the last few days about
01:36:38 discussion on the last few days about the combustion process so you need the right quantity of fuel air and heat so to have a good combustion process that also supports flaming so clearly the
01:36:51 also supports flaming so clearly the gaps in the panels and the other amines for air to end that environment provided an adequate air supply because we observed perfectly
01:37:03 air supply because we observed perfectly effective combustion and flame and combustion yep and is it right that in your assessment that these columns were the principal route for vertical flame spreads that your assessment principal
01:37:15 spreads that your assessment principal route yes in the beginning yes correct you say that paragraph five point five point yeah and do you agree with professor Bisbee that flames elongate up
01:37:26 professor Bisbee that flames elongate up to five to ten times their expected length in a concealed space is that kind of recognized I agreed that they elongation a concealed space yes and
01:37:38 elongation a concealed space yes and you've indicated that there are gaps of around 139 millimeters in depth between the face of the Rana bond panels and the outer face of the insulation over the column yes yeah is that based on your
01:37:50 column yes yeah is that based on your sight observations and measurements yes so I did some measurements yes but I've been thinking about this again because of this little detail on the drawing
01:38:01 of this little detail on the drawing where there's that movement all the time so there must have been other locations if you think about geometry when it was bigger or smaller yeah basically on in the building when it was completed when
01:38:13 the building when it was completed when the works were complete you say that the cavity may have varied it should it should have yeah if you think about this variation that was needed beside the window all the time yeah so then the
01:38:26 window all the time yeah so then the column panels had to connect into the spandrel so there must be some change occasionally yeah and then we also have
01:38:37 occasionally yeah and then we also have vertical cladding rails the full height of the building is that correct that's right and we have these cutting rails at the tips and also at the edges of the columns these unbroken pathways Saticoy
01:38:49 columns these unbroken pathways Saticoy and again do you think those are significant I think they're significant in terms of vertical flame spread or the potential of a vertical flame spread I for me it's the material and the panel
01:39:08 I for me it's the material and the panel is the significant feature the channels form of what you know it's like one big long void
01:39:17 long void they broke the cavity barriers too but the cavity barriers you know are impacted by the material in the panel as well so yeah I couldn't say that I
01:39:28 well so yeah I couldn't say that I thought the channels were very significant or again a governing parameter in terms of the vertical spread of flame I'll say it's one more
01:39:39 spread of flame I'll say it's one more thing rather than the most dominant thing if that's okay yeah yeah and just to be clear in terms of the vertical channels that we're there you have one at the column tip we saw that yesterday
01:39:51 at the column tip we saw that yesterday and yes professor Bisbee stirrings but then also down the side where you've got the line D is it right that there's potentially a cladding rail with a panel
01:40:04 potentially a cladding rail with a panel coming in to it on either side and you sometimes have get rails at the side of those columns that could have also provided a vertical route well on on that so on the corner columns yes the
01:40:18 that so on the corner columns yes the condition is is different so on these on these columns here you'll see there's two panels come together in a point but
01:40:30 two panels come together in a point but at the coroners they they look almost like a rectangle and so you have two channels there yeah and you've actually identified we're going to come back to this that
01:40:41 we're going to come back to this that there might have been a reach of flame spread behind those columns is that correct yes but but where the column panels meet the building yes yes they
01:40:52 panels meet the building yes yes they interface remember with the laterals yeah there is a connection there yes there's a cladding rail they're a small one yep yep and you've noted in your
01:41:05 one yep yep and you've noted in your report at the top of column B five on the east face was on fire within approximately 12 minutes of emerging from flat 16 yes that correct and you've also noted the ability of fire to spread
01:41:18 also noted the ability of fire to spread both up and down the column yes can we just look at that so let's look at figure ten point nine yeah of your report that's BL a s yeah five zeros ten
01:41:29 report that's BL a s yeah five zeros ten at page 11
01:41:39 yep we can zoom in on that figure yeah so I believe this is column B one which
01:41:51 so I believe this is column B one which is on the west face yeah correct and it's pretty obvious what you're drawing attention to here but this seems to show an illustration of what you're referring to here this mechanism of downward fire
01:42:03 to here this mechanism of downward fire spread yeah and you just explained the processes you think might be going on there that we're seeing in that in that image so at this stage when the flame fronts down here but of what what I can
01:42:15 fronts down here but of what what I can see is the material the core of the ACP but you have to observe it from the top and there's all sorts of video footage and the helicopter footage shows that
01:42:26 and the helicopter footage shows that much better than this photo but you see initially liquid burning polyethylene igniting the the ACP panel and then some
01:42:43 igniting the the ACP panel and then some kind of combustion process commences an effect of combustion process and enough gases enough products of combustion are produced to allow flame and combustion
01:42:55 produced to allow flame and combustion and you can see it progressing down through the materially the ACP panel on the column but at times also when you're looking at the moving footage it then
01:43:07 looking at the moving footage it then starts it heats up laterals as it leaves them in its wake as such and then those laterals have received enough heat that fires start on either side of the column
01:43:18 fires start on either side of the column also and the column the flame front progresses down where it's fueled by the combustible materials present there is
01:43:30 combustible materials present there is that an exact we can see kind of on the right there's a kind of line on the right of that flame at the top where the window is there's that kind of where you can start to see it going did you here yeah right yeah yes yeah yeah and
01:43:47 here yeah right yeah yes yeah yeah and you you give the mechanisms for downward fire spread at ten point three point two three of your report can we just go to that let's be la s five zeros
01:43:58 that let's be la s five zeros ten at page 14 and you highlight two key things here the polyethylene from the
01:44:09 things here the polyethylene from the rain LaVon pan of melting and running down the building and down the column yeah this is pathway a yeah and you also talk about radiation from the fire within the cavity heating materials
01:44:21 within the cavity heating materials below within the fire within the cavity can you just talk about that latter part yeah so I think but before you see a flame there's all sorts of things
01:44:32 flame there's all sorts of things happening to materials under when they're being heated so as the flame front is progressing it's kind of like it you can't see it but the materials
01:44:43 it you can't see it but the materials and from there being heated you know it's heating the materials as a go there's all sorts of heat transfer effects going on and the materials around it and when that when they're
01:44:55 around it and when that when they're preheating if you will is occurring there's gases being produced and at some point they form a system that can support flaming so I think as when when
01:45:06 support flaming so I think as when when there's a fire on a panel it is heating the materials in the cavity bottom behind it and you're talking here specifically about downwards as well
01:45:17 specifically about downwards as well yeah that are you saying that the columns are effectively kind of enclosed space yes it'll be gay I think you did yeah it's it's not cold in it's not you
01:45:29 yeah it's it's not cold in it's not you know it's not freezing cold in front of the flame front no matter at the direction yeah it may be slightly different temperatures but it's not freezing cold in front of the flame front and nothing's happening around us
01:45:41 front and nothing's happening around us okay let's move then to pathway B that you've identified and you have this as horizontal spread across the Reina bond span
01:45:51 span panels can we just go back to your BL as50 is ten at page five and figure ten point two and just look at that so here
01:46:07 point two and just look at that so here we have in the the darker blue be across those yeah yeah and you say something very specific about this you say that the panels contained a number of gaps I
01:46:20 the panels contained a number of gaps I think what you're drawing attention to is the gaps between the spandrel panels those are the black lines yes and si going with exposed P cause yes and that those gaps permit air into the cavity
01:46:33 those gaps permit air into the cavity and trap the flames and hot gases which are then trapped by the return of the panel as it meets the concrete's panda at the windowsill is that correct yes let's just look at figure 10.26 so you
01:46:45 let's just look at figure 10.26 so you can explain to us precisely what you're trying to illustrate here so that if that the gap that you're referring to
01:46:57 that the gap that you're referring to there above there yeah the window so there I'm showing you that you know the two panels are not not flush against each other by design their record you
01:47:09 each other by design their record you know they need have a ventilation gap between them yep and what you're saying is you think that that's a space that flame will will be attracted to and go
01:47:20 flame will will be attracted to and go up yeah I saw a flame can enter there and give us heating in behind our panel when it's in position yes and you're also drawing attention to the exposed polyethylene edges is that correct yes I
01:47:33 polyethylene edges is that correct yes I am and again I think professor Bisbee explained to us that around those corners you've got a number of exposed PE edges yes is consuming his yes that's his figure on the other correct yes sir which you think is significant yeah and
01:47:46 which you think is significant yeah and is it right then that once you you think there's flames in these channels you think that it can then be a route to spread across the planet the panel's that's correct so again you have you know as as we are observed
01:47:58 know as as we are observed as you you know observed from the footage on the night there's clearly a perfect flaming combustion process created and that's how the flame was able to travel in both directions along
01:48:11 able to travel in both directions along the laterals you've the fuel on the outside layer the insulation layer you've air and so I'm just going to call it a perfect combustion process was
01:48:22 it a perfect combustion process was clearly made yeah and can we just talk a bit about that the bit immediately above the window goes back inside do we have an exposed PE edge around the
01:48:34 do we have an exposed PE edge around the back of those panels so you mean where it comes in towards the top of the aluminium window frame oh but my understanding is it is exposed there but
01:48:46 understanding is it is exposed there but now that you've asked me I'd want to frantically look at all my photos in Appendix C to check I think the busy feel there might be a small it depends a bit like we see on that yeah it depends on how the flat panel was cut yeah
01:48:58 on how the flat panel was cut yeah actually there so I would me I would have to look out so I don't know which part of the flat panel was cut and which part was folded in that exact location yeah and you think that those cut edges
01:49:10 yeah and you think that those cut edges themselves would have promoted horizontal flame spread is that correct
01:49:18 well well the Cottagers expose fuel to the looming flame front that's what I mean yeah do you agree that any
01:49:30 mean yeah do you agree that any horizontal or lateral flame spread here would be very effectively opposed flow flame spread so it's going to the side rather than up and therefore it's likely
01:49:42 rather than up and therefore it's likely to be slower oh yes you have been vertical flame spread yes i I do agree with that and again there is very good visual evidence of that of it the
01:49:54 visual evidence of that of it the difference in rate yeah a bit moving that's most yeah of it moving so again we explored that with yes this is a mechanism do you accept this is going to be a much slower mechanism than what we
01:50:06 be a much slower mechanism than what we would see for example with vertical flame spread for example at the column so much slower you know in park context I think that it's it moves slower than
01:50:19 I think that it's it moves slower than the flame front on the column yeah but I think it's a perfectly effective flame front whether it's speed is greater or less than the column is not significant
01:50:32 less than the column is not significant to my mind let's look at a pathway see this is horizontally across the edges of
01:50:43 this is horizontally across the edges of the head and sill of the windows and the edges top and bottom of the insulating window panels let's just look at your marked up figure 10.30 BL as50 Sten at
01:50:58 marked up figure 10.30 BL as50 Sten at page 30 yeah you can zoom in there yeah now can you just point out where on this
01:51:10 now can you just point out where on this diagram you say we are seeing this horizontal let's focus on the head and sill of the windows for the moment yeah I was trying to show you know
01:51:24 yeah I was trying to show you know particularly here that the combustor I got the construction products there are now or flaming also yep so your look
01:51:39 now or flaming also yep so your look tonight right yeah you're looking at these little lines of flame yes I'm sorry the head and bottom of the window yeah and if you pick if you pick one of the lines when I can't do there but if you if you pick one of the lines just up
01:51:52 you if you pick one of the lines just up through that elevation you can you tend to be able to find moving up horizontally or vertically just on the
01:52:04 horizontally or vertically just on the edges not engulfed thing a whole panel yeah yeah and just to be clear I mean it's difficult to tell from these pictures but what do you think maybe burning there along the head and sill of the windows you know I imagined that the
01:52:22 the windows you know I imagined that the construction materials there were burning and what materials are we talking about oh right side just around the window yeah yep so you're talking about the
01:52:33 yeah yep so you're talking about the insulation materials around the window oh yeah so I mean exactly so I've said that there was there was you PVC on the inside and then you had the timber if you're after sale you have the timber
01:52:44 you're after sale you have the timber sale you've got the insulation so it's all those components with all those components particularly when the ACP panel is gone okay yeah that's what I
01:52:55 panel is gone okay yeah that's what I meant
01:52:55 meant yes yep yep so you said that involves the combustible materials that make up the window surrounds including the polymeric insulation which was used to
01:53:07 polymeric insulation which was used to fill the gaps which we looked at earlier yeah you've also referred here to the window infill panels yeah we're going to look at these panels on a number of occasions let's just be clear what the
01:53:18 occasions let's just be clear what the window infill panels are they those white panels that we see in the bottom left there's still some remaining there that's correct the alley glazed infill panels now is it right that those were
01:53:30 panels now is it right that those were extruded polystyrene often referred to as XPS is that correct yes that's correct and can we just be clear of what
01:53:41 correct and can we just be clear of what these are is it right that they're two layers of aluminium and a styrofoam core which is made up of this extruded polystyrene is that correct that's correct yeah and I think you say in your
01:53:52 correct yeah and I think you say in your report that we have 25 millimeters of the styrofoam core and then one point five millimeter aluminium sheets on either side is that correct and
01:54:04 either side is that correct and professor Bisbee has set out the properties of XPS in his report paragraph four 37-foot for the note and he says they have a melting temperature of 230 degrees C is that your understand
01:54:21 of 230 degrees C is that your understand yeah yes yes and and you have them here as part of your pathway see horizontally along the top and bottom of those window panels and can you just explain to us
01:54:35 panels and can you just explain to us how you think they may have played a role in terms of horizontal flame spread in terms of horizontal flames yeah that's your your pathway yeah so
01:54:48 yeah that's your your pathway yeah so the should we go back to that image yeah yeah yeah can we go back to the image that we had a moment ago yes exactly oh yeah so if we just look maybe at the top right of that image about what
01:55:00 top right of that image about what you're trying to so when I was referring to the pathways horizontally along the panel's again I'm speaking about the materials surrounding those panels I
01:55:12 materials surrounding those panels I come on later to the panel itself so so again the panels were inserted into an aluminium aluminium frame and again you had the voids underneath those you had
01:55:25 had the voids underneath those you had combustible materials on all sides of those panels too and I wanted to draw attention just separately that again around not just around the window
01:55:38 around not just around the window openings but around those alyou glaze openings if you want if you will again there there is a line separate to the panel that is formed with combustible
01:55:49 panel that is formed with combustible materials yeah the panel itself is a different path yeah I think so you have combustible material down the side against around and got yeah and along the top along along along the top or
01:56:03 the top along along along the top or bottom side and both lateral sides yeah okay and
01:56:09 yeah it's probably worth noting that yeah there aren't any drawings that exist of the detailing there right so I have to rely on just what I saw on site
01:56:21 have to rely on just what I saw on site on photos like this yep yep professor Bisbee was taken to this image and he says what he thinks you can see in some
01:56:32 says what he thinks you can see in some of those instances is actually Poole fires burning at the bottom of those window infill panels yes do you think that might be correct I think that some could be Poole virus and I think others
01:56:44 could be Poole virus and I think others could be the construction materials burning yep yeah so I I agree with his perspective anything I don't think there
01:56:55 perspective anything I don't think there are all Poole fires and I don't think they're all the localized construction materials yeah and if you have a pool fire there at the bottom of one of those panels of one of those at window window
01:57:08 panels of one of those at window window infill panels at the bottom of the alley and the along the edge along the bit the base of those panels along the ledge you have a pool fire there what's your expectation in terms the performance of
01:57:19 expectation in terms the performance of that panel given what we know about it so if you mean if the pool fire has come from somewhat so it slid from somewhere else it's managed to pool on the Tilted panel yonder the window and there would
01:57:33 panel yonder the window and there would then be a localized heating condition of the the next panel so the al you glaze panel yeah and they don't appear to have been the mechanically fixed into the
01:57:44 been the mechanically fixed into the aluminium frame they're just seem to have just been snapped in okay so I would expect the aluminium on the outer face to heat up and quite easily
01:57:57 face to heat up and quite easily relatively easily distort and also allows the conduction of heat through it into the styrofoam which degrades very
01:58:09 into the styrofoam which degrades very nicely under heat when you talk about distort what you're talking about is is the distortion of the aluminium panels on either side of the styrofoam is that yeah well actually multi-drop
01:58:20 yeah well actually multi-drop multi-directional so it depends for temperatures where so a relative distortion of the front and back face but actually distortion along this plane also as a function of where
01:58:31 this plane also as a function of where the heat is at the front yeah and once they distort and there's a fire near then what do you expect to happen I think that distortion so first of all there's a heat transfer into the core
01:58:43 there's a heat transfer into the core and the you know aluminium can't stop that from happening so with heating anyway and then any kind of distortion that allows the you know and I say the edges of the styrofoam to be exposed or it might be the panel can
01:58:56 be exposed or it might be the panel can actually snap out of the aluminium frame but the overriding condition is the the styrofoam being heated through the metal
01:59:07 styrofoam being heated through the metal face it's probably worth saying that those panels al you glaze we did some cards they they make up about you know
01:59:20 cards they they make up about you know sixteen or seventeen percent yeah the external wall so they have they're relatively low proportion yeah can we just have a look at figure 10.35
01:59:31 can we just have a look at figure 10.35 yeah
01:59:32 yeah [Music]
01:59:39 yes on BL as50 is 10 at page 37 yes this is it if we zoom in on the figure at the
01:59:51 is it if we zoom in on the figure at the top of that page so this is post-fire yeah we can see some of the a-league laze panels is the kind of distortion
02:00:03 laze panels is the kind of distortion that you were talking about evident on any of those photographs yeah so I I think I can see it just so here
02:00:14 think I can see it just so here potentially and obviously here as well yeah that one in the middle the lower one in the middle can we assume in on that one in the
02:00:28 can we assume in on that one in the bottom do you think that's an example of the distortion yeah because I think the core you know I don't think it's a nice even the aluminium isn't over anything
02:00:41 even the aluminium isn't over anything even anymore yeah yeah those panels were not backed back themselves by any insulation I know they had insulation down the sides and the top he just said
02:00:52 down the sides and the top he just said but they weren't backed by that insulation is that correct those that those panels are insulation that's their purpose and that's what the styrofoam is far
02:01:08 yeah and let's just have a look at what those panels look like before they've been that's just go to figure 56 of Luke Bisbee's report lb why is six zeros one
02:01:19 Bisbee's report lb why is six zeros one at page 96
02:01:42 yeah if we look at the top if we can just zoom in on the top so this is a picture of one of those panels I think that was provided by two professor Bisbee so is it right we there we can see the 1.5 mil aluminium sides and then
02:01:56 see the 1.5 mil aluminium sides and then the 25 mil styrofoam cores that correct [Music]
02:02:02 [Music] yep yep I think professor torero said in his evidence that when this burns there's a lot of air in it and it kind of burns to nothing or you know because
02:02:13 of burns to nothing or you know because I asked him what could it create a pool fire in itself do you have a view on that I'm not aware that polystyrene burns to nothing but I wouldn't take
02:02:24 burns to nothing but I wouldn't take professor Theriot our Novation any scientists when I asked him would it melt and potentially create its own pool fire he said he didn't think it would because there's a lot of air in the
02:02:36 because there's a lot of air in the product okay so that's that's not my my understanding in not to do with this not to do with alyou glaze specifically but in general the reason why polystyrene
02:02:47 in general the reason why polystyrene sandwich panels are are you know so negatively viewed in construction is the polystyrene forms a liquid and degrades
02:03:00 polystyrene forms a liquid and degrades the panel's so quickly you know in a fire and there's a lot of yeah I'm gonna take you back because we're going to look at the properties of it some of these specific materials and remember
02:03:12 these specific materials and remember this frames that he said it shrinks away from the flame yes starring melted yeah
02:03:26 from the flame yes starring melted yeah yeah do you think that these Alagoas panels would have behaved differently to the ACM cladding panels they both have a another mininum skin to them with a with
02:03:38 another mininum skin to them with a with a core and is there any kind of comparison as to how they behave in terms of warping deforming flaming oh I see
02:03:48 see I think I think the key characteristics of the core getting hot the core of being combustible the panels you know the aluminium on both sides maybe under
02:04:00 the aluminium on both sides maybe under some all very complex potentially thermal gradients are are the same are similar yeah yeah characteristic of them
02:04:13 similar yeah yeah characteristic of them yep
02:04:14 yep just finally on this rootsy topic you've also mentioned that here the I think you said it earlier the original timber window frames and reveals that were left in there yeah and you felt that that
02:04:27 in there yeah and you felt that that might have been important once the windows on fire in terms of horizontal spread across the window is that correct yeah yep pathway D we go back to your
02:04:38 yeah yep pathway D we go back to your figure ten point two and we look at this so pathway D says vertically along the
02:04:49 so pathway D says vertically along the window edges and also along the edge of the alig lays yes relating core panels I mean that's so kind of completing the exactly it's to say you know we've talked about it's about the construction
02:05:01 talked about it's about the construction around the edges not the panel itself still yeah yeah and professors Bisby drew attention yesterday to the fact that down the sides of the columns by the window you've often got exposed PE yes along those edges again do you think
02:05:14 yes along those edges again do you think that's potentially important in terms of vertical spread along those window edges the exposed PE on on the user as it
02:05:25 the exposed PE on on the user as it comes back and hits the window so do you mean on this edge facing the column or at the top edge sorry no on
02:05:35 oh yeah so that there's no aluminium foil there we'll come back to that on the PIR I think he was talking about
02:05:46 the PIR I think he was talking about that the ACM cassettes themselves yes because they come back and hit the window yeah an exposed PE line down there yeah so I think small details like
02:06:01 there yeah so I think small details like that are important for a very short period of time at the start of a very smaller fire yeah my own view is is that when you have a very well-established flame front it's like overwhelming all
02:06:14 flame front it's like overwhelming all these small details so that's why yeah yep okay are you're drawing attention to all of these routes there's potential routes that you've seen on Grand Vitara yeah but the relative contribution of
02:06:26 yeah but the relative contribution of them exactly I'm just trying to show that at every turn if you will there's something there that can participate in
02:06:37 something there that can participate in a combustion process yeah so all the time the flame front has something that will allow it to carry on that's all I'm trying to say yeah can we look at and
02:06:51 trying to say yeah can we look at and just on this pathway D before we leave it figure ten point three four of your report B la s five zeroes ten at page 35 and you've specifically labeled and
02:07:05 and you've specifically labeled and drawn attention here to vertical fire spread between the insulating core panels can you see that in life we zoom in on that line yeah so we're back on
02:07:16 in on that line yeah so we're back on the edge of the earlier glaze you know are we yeah so we were looking horizontally before but you've highlighted vertically here we can see a very clear nine is that what yeah yeah I
02:07:27 very clear nine is that what yeah yeah I was trying to show that yeah yeah and again do you think that might be because of the insulation down the side there or yeah the edge of the panel has caught and deformed deep can we tell you no I
02:07:39 and deformed deep can we tell you no I mean I can't I can't tell that from this photo but there is a sizable piece of insulation capping the alyou glaze there
02:07:50 insulation capping the alyou glaze there on the inside yeah yep you've then got pathway II it's vertically by means of the ally glazed panels connecting with
02:08:03 the ally glazed panels connecting with the spandrel pan yeah let's just go back to your BL as50 Sten at page five yeah and look at the diagram of your six
02:08:15 and look at the diagram of your six pathways yeah so pathway II here you're drawing attention to have vertical flames but as between these yeah white panels is that correct yeah that's
02:08:26 panels is that correct yeah that's correct
02:08:27 correct so if you have for example flame and peridot EE actually is on the drawing yeah you know again above that there isn't glass okay there's another
02:08:40 isn't glass okay there's another combustible sandwich panel and that can then also contribute in some way to fire spread in that localized area between one spandrel and the next you've
02:08:53 one spandrel and the next you've highlighted a particular photo here that's ten point three seven that's BL as50 ten at page 39 yeah can you just talk us through the bits that
02:09:04 you just talk us through the bits that you were wanting to highlight on that picture yes so I I just I just marked up you know using the column locations the location of the Al you glaze you can see
02:09:18 location of the Al you glaze you can see if you just follow the blue dotted line going from the top to the bottom of the picture from the bottom up to the top just trying to show that there does appear at times to be a localized
02:09:30 appear at times to be a localized vertical flaming effect yeah the spandrels are very important in that or the ACP is but in those local air there is also the other panel yep
02:09:43 there is also the other panel yep professor torero thought that the total mass of energy might be relatively small that would be produced by these panels when they burned although he agreed that they would burn and potentially play a
02:09:54 they would burn and potentially play a role would you agree with that yeah I think you know to me is like I said earlier I think they make up about 15% of the overall surface area so they're
02:10:06 of the overall surface area so they're present but in the scale they're installed a grand full tear it's a 15 you know it's a 15% based on surface so
02:10:17 you know it's a 15% based on surface so I mean I'm not going to call that some you know very dominating feature to me it's just it's one more material can we
02:10:29 it's just it's one more material can we look at your final pathway that's pathway F around the crown of the building yeah and again can we just be clear what the crown is we refer to it
02:10:42 clear what the crown is we refer to it as the crown what what is it if we have a look at VL as50 10 page 69 figure 10 point 7 3 before
02:10:53 10 page 69 figure 10 point 7 3 before what is it yeah what's its function on the building to me I mean it's it's an architectural feature yep but I don't know what they thought of was yeah yeah
02:11:09 it's just to make the top of the building and just like here we again we looked at this in detail we have these c-shaped channels these yeah some people I think that you call fins that go
02:11:20 I think that you call fins that go vertically down and then we have a particular detail at each of the top column tops yeah that's made up of just eight ACN panels it appears to be yes ACP panels yep yeah can we look at
02:11:34 ACP panels yep yeah can we look at another figure of yours figure 10.4 oh the l as50 is 10 oh yeah age 43
02:11:45 do you know how many of those fins were left after the fire oh no I do now didn't count them yeah yeah from this photo doesn't look like many are left no
02:11:57 photo doesn't look like many are left no but I mean I can see bits of thin about me I don't know if the polyethylene is there I doubt it though yeah and is it right you say that there was no
02:12:08 right you say that there was no provision made to inhibit horizontal fire spread around the crown is that right yeah so the drawings don't show cavity barriers or any other material to
02:12:20 cavity barriers or any other material to prevent that and you also specifically note in this part of your report that there were a large number of deaths on level 23 which is a nearly below this crown what do you think just overall
02:12:33 crown what do you think just overall before we look at it in more detail what do you think overall is the significance of this particular fire spread path are you asking me that in the context of the death of level as we knew it just intensive as a fire spread route okay
02:12:46 intensive as a fire spread route okay how important do you think it was in that inside context yeah once the flame got up to level 23 in the first place above flat 16 yep and it appears then to
02:12:59 above flat 16 yep and it appears then to have been you know been able to travel horizontally laterally horizontally in both directions through the crown and the helicopter footage and other mu you
02:13:10 the helicopter footage and other mu you know moving images shows the flame front progressing but more importantly causing extensive pools of burning polyethylene
02:13:23 extensive pools of burning polyethylene to flow down to the spandrels above those flats and more significantly down other columns I don't know the order of
02:13:34 other columns I don't know the order of the morph by heart sorry but they it burnt causes burning of the laterals and the ignition of more and more columns as that flame front progresses yep so it's
02:13:45 that flame front progresses yep so it's significant in the context of causing in the timing we saw at Granville
02:13:53 more columns being involved that way yeah and it is significant a Beaufighter did to level the flats at level 23 do
02:14:05 did to level the flats at level 23 do you agree with Professor Bisbee it says what you do that therefore lateral spread was most rapid at the crown it was fastest at the cranium III haven't happened on timing analysis but yes it was a highly effective flame
02:14:17 yes it was a highly effective flame front yeah along the crown highly effective yeah and do you also agree that it's most likely the primary route of horizontal plane spread around the building because of this falling melting
02:14:29 building because of this falling melting debris which then accumulates at lower levels and then sets fire to levels down the tower which then travel upwards creating this diagonal effect I think I
02:14:40 creating this diagonal effect I think I think yeah so did you say it's the most effective horizontal yes overall in the whole building that's that does seem to be professor Bisbee in Toreros evidence that that's
02:14:51 Bisbee in Toreros evidence that that's the the most that's the primary of horizontal flame spread around the building okay that's an interesting thing to me it it was a rapid horizontal
02:15:05 thing to me it it was a rapid horizontal spread of flame that core in that time caused other vertical and then horizontal yeah yeah I think I think I agree with them I'm not entirely sure what the significance is I think I agree
02:15:17 what the significance is I think I agree Turner at that time yes yes it was a the most important horizontal right but later on the other lateral flame fronts
02:15:31 later on the other lateral flame fronts became important then didn't they because the crime wasn't involved anymore yeah yeah so you're drawing attention as I understand it to the fact that well they're you accept that lower
02:15:42 that well they're you accept that lower down the natural thing so it might be slower yeah it's still yours you say plays a role at it in the later stages of the fire absolutely once it's gone round yeah and we've got all areas of
02:15:53 round yeah and we've got all areas of the crown ignited yet you've still then got in the steel yeah you still have other flame fronts lower down the tower so it's a really important root
02:16:04 so it's a really important root at that time later on when you plot the you know the flames coming down the columns and the flames moving away from each one of those columns you're just getting more and more horizontal and
02:16:16 getting more and more horizontal and more horizontal runs yep can we just look at the characteristics of the architectural crown in terms of fire
02:16:27 architectural crown in terms of fire spread laterally if we can look at figure 34 of professional Bisbee's rapport that's elbe wire six zeros one at page 63
02:16:48 yes let's just look at the let's look at figure 34 first at the top where he's done a horizontal section through the crown so is it right that what we have
02:17:00 crown so is it right that what we have of these C shaped ACM channels which then slot into aluminium cladding rails behind them is that correct that's what that drawing
02:17:11 that correct that's what that drawing shows so there's no insulation in this part of the building it's just a CM on these padding layer currently not yes yep and professor Bisbee's view is that
02:17:22 yep and professor Bisbee's view is that these provided a semi continuous path for fire to spread around the crown would you agree with that yes I would he also has drawn attention to numerous exposed ACM edges in the way this was
02:17:35 exposed ACM edges in the way this was configured yeah again would you agree that that's potentially significant again they're dope dose that those small details are important at the very start
02:17:46 details are important at the very start of a small fire when you have a very well of well-developed French flame front no no I don't think the fact the edge is exposed is a very big governing
02:17:57 edge is exposed is a very big governing parameter but but there are plenty of them there and they the each individual fan could create its own flame front which could very easily ignite the next
02:18:09 which could very easily ignite the next fin and he's also drawn attention to the fact that effectively these are C shaped chimneys which might support flame
02:18:21 chimneys which might support flame extension again would I do I jumped yeah I don't think I need to give a view on that yeah and he's also drawn attention to the fact that there was no cavity
02:18:32 to the fact that there was no cavity barriers anywhere in relation to this architectural detail is that correct yeah so my understanding from the drawings which are very limited there there are no cavity barriers marked
02:18:44 there are no cavity barriers marked there once you get above level 23 just looking in that drawer would it have been a practical possibility to insert some sort of
02:18:59 possibility to insert some sort of material between each of the fins do you see what I know no I do not hear I think if you're asking me could you have installed cavity barriers anywhere after chrome to stop the flame from suis
02:19:11 chrome to stop the flame from suis observed my view is no the best way to because it was too well-developed of that that's I don't know how you could the only way you could stop the chrome
02:19:22 the only way you could stop the chrome from being a flame front on its own is to not cloud it in a combustible material trying to detail in little bricks or cavities it's not crappy in my
02:19:33 bricks or cavities it's not crappy in my opinion it's not a practical mitigation measure the best mitigation measure would be not to have that material there at all I think I'm probably straying beyond what's right phase one juicy yep
02:19:48 beyond what's right phase one juicy yep and just to be clear you don't think that that actually the the speed of the fire at that level can simply be explained by the fact that the fire
02:19:59 explained by the fact that the fire plumes out and and spreads out at the top as opposed to it being about the crown as explained as a flame rises up it will naturally Yeldon as the flame
02:20:12 it will naturally Yeldon as the flame goes up a face it'll naturally plume out yeah as a top you don't think what we can see at the top of the building is more about that effect than about the crown oh you mean do you mean that when
02:20:24 crown oh you mean do you mean that when a flame front came up say the first column that we're not seeing the crown burning we're seeing something burning from the column clouding that's been suggested oh oh I wouldn't think that at all yeah it might be for the first few
02:20:38 all yeah it might be for the first few seconds but then that just ignites the crime doesn't us and it progresses and again do you think the fact that and so the edge of the roof was capped with an aluminium coping and we can look at this
02:20:50 aluminium coping and we can look at this in a drawing if you go to figure ten point four seven BL a s yeah five zero is 10 at page 48
02:20:59 this is one of your drawings yeah which we've looked at earlier this week so what we see at the bottom of this is how the panels were configured at the very top of the building which gives me
02:21:11 very top of the building which gives me a spandrel panel and installation behind it sitting above that was an aluminium flashing or coping over the top of that and then fins the architectural fins on
02:21:23 and then fins the architectural fins on the top it's been suggested that some of that aluminium coping was very melted
02:21:34 that aluminium coping was very melted immediately above that insulation or below the fins but not on the edge and that that might be significant do you have a view on I don't have a view on doesn't know mr. chairman I'm about to
02:21:48 doesn't know mr. chairman I'm about to move to another topic I'm either happy to keep going or to have a five-minute break would you like a break at this point how much longer after would have much longer will we go if I don't have a
02:22:00 much longer will we go if I don't have a brain would normally stop for lunch at one o'clock so that's I think I would actually just prefer a very short break yes that's okay we say five minutes yes please yes right
02:22:12 we say five minutes yes please yes right well we'll have a five-minute break please same as before don't talk to anyone about us you go with you
02:22:28 twenty past twelve
02:26:44 can you take your seats please and remain silent thank you
02:27:48 right dog okay carry on yeah thank you good thank you so and just to summarize overall your evidence is that once the fire is in the cladding it facilitated and promoted flame spread in you say six
02:28:00 and promoted flame spread in you say six different ways that's correct that's correct and you've identified that the Reina bond 55 PE is responsible for the most rapid of the observed external
02:28:11 most rapid of the observed external frame spreads that's correct does that remain your view it does remain my view what is your view about the significance of the PIR insulation in terms of flame spreads you may have heard both professor torero and
02:28:24 heard both professor torero and professor Bisbee and on this topic yeah what contribution do you think the PIR had to the speed and extent of the fire spread if any yeah so I would like to be
02:28:37 spread if any yeah so I would like to be able to refer to a drawing please in my report figure at 8.11
02:28:52 is 8.11 is on BL a s60 is eight page 13
02:29:01 and it's figure 8 11 is the far right hand yes drawing do you want us to zoom in on that yeah that would be great yeah
02:29:12 in on that yeah that would be great yeah I use this drawing a lot when I'm thinking about events or grande fold her so it in this drawing you can see in the
02:29:26 so it in this drawing you can see in the condition where there's just a small 35 millimeter graph you can see the insulation relative to the ACP when the gap is larger it will look somewhat different and my view is that having a
02:29:42 different and my view is that having a you know I've been talking about a combustion process and combustion in a system and I think in a system with a combustible layer on the inside and a
02:29:54 combustible layer on the inside and a combustible layer on the outside even before flaming combustion can happen when you have a heat source those materials are breaking down they're
02:30:05 materials are breaking down they're producing gases they're getting ready if you will to produce the perfect mix for a flame and combustion it's a huge expert area in its own right combustion but from my perspective the
02:30:18 combustion but from my perspective the Celotex are any insulation in in that in the cavity in the system contributes pyrolysis gases to the system and the
02:30:31 pyrolysis gases to the system and the system needs that to create that perfect mix for a flame and combustion I don't think I heard either professor
02:30:42 I don't think I heard either professor torero or professor Bisby say that didn't happen I I got the impression they said they couldn't quantify it or predict it which i think is a very
02:30:53 predict it which i think is a very different very detailed view you know in their minds that's very detailed can you predict it exactly second-by-second millimeter by millimeter but the concept of having you
02:31:07 millimeter but the concept of having you know pyro prioritizing material on the left the insulation and the ACP on the right
02:31:13 right I think it's creating a highly effective system and I understand the scientists will need to work out the numbers behind us and I think therefore in that context
02:31:25 us and I think therefore in that context of how it performs when it's heated the gases it produces in in the pyrolysis process is all part of that combustion
02:31:36 process is all part of that combustion system and the flaming combustion that we see and for me I think it's very important do you draw any conclusions
02:31:48 important do you draw any conclusions from the eight for one for testing which was done after Graham Phil referred to by Professor Bisbee I under D CLG tests which sought to compare the PIR type of
02:31:59 which sought to compare the PIR type of insulation that we saw at Graham full with say stone wool insulation but using otherwise similar materials to Graham for do you take anything from that at this stage I don't take anything from those tests because I don't think those
02:32:12 those tests because I don't think those tests I don't consider them to be relevant because they're so far away from the kind of construction detailing that people like me have to worry about
02:32:24 that people like me have to worry about in our profession and I would make no comparison of any material in that testing regime and I would prefer to
02:32:36 testing regime and I would prefer to keep all the other views I have to myself at this stage and I'm happy to write a very detailed chapter on the subject because I will absolutely not compare a mineral wool with a PIR
02:32:50 compare a mineral wool with a PIR material from that test program no that's care
02:32:59 and have you heard or seen any other evidence in these proceedings which has caused you to change your view as to the primary responsibility of the Reina bond
02:33:10 primary responsibility of the Reina bond 55 P for the rapid flame spread that we saw at Granville no no and your view is that the cladding as it was configured
02:33:23 that the cladding as it was configured at Grenville rendered it unsuitable for a stay put policy is that correct yes it is before we leave flames spread just are there any other aspects of Professor
02:33:34 are there any other aspects of Professor Bisbee or professor Toreros flames spread analyses that have caused you to modify your views is anything specific you hunter pick up I didn't listen to their evidence properly in the last few days but I will and I will let you know
02:33:45 days but I will and I will let you know but I'm not at this time now do you think it would be helpful at all to do any kind of survey of the respective volumes of for example the PIR
02:33:57 volumes of for example the PIR insulation the ACP the Ali glaze to serve survey the extent to which it was installed and then also to survey the post fire condition do you think that can tell us anything about the
02:34:08 can tell us anything about the respective contributions of these materials is that an exercise you think will be worth while doing survey to quality the higher building to quantify for example what's left but there's
02:34:19 for example what's left but there's nothing left in most places at all if you could do a survey based on the records of the removal of what was left do you think that would be a useful exercise I certainly don't need anything from a survey like that yeah
02:34:30 from a survey like that yeah just one final specific question on this at paragraph eight point two point eight of your report be a layer six zeros eight page four can we just look at that
02:34:45 so that's eight point two point eight yeah you set out a definition here of a combustible material because it's a material that will ignite and burn when sufficient heat is applied and when
02:34:56 sufficient heat is applied and when appropriate oxidizer is present and you have that from dinner dinner to have their hand sorry two thousand seven and do you agree that this definition would
02:35:07 do you agree that this definition would result in mineral fiber and aluminium being classified as combustible to mineral fat sorry mineral fiber and aluminium being classified as combustible so mineral wool is non
02:35:22 combustible so mineral wool is non combustible the binder is used to packer together are combustible yeah but I find those arguments quite trite when one
02:35:33 those arguments quite trite when one compares mineral wool with a polymeric foam of equal thickness and the same goes for aluminium I understand that nearly everything in the world can burn
02:35:44 nearly everything in the world can burn yeah but in the context of construction I like to keep things appropriate and relevant and understand that a mineral wool is substantially less combustible
02:35:57 wool is substantially less combustible and in fact typically defined as non combustible if I test do you agree that the regulatory definition of non combustible 'ti is based on the total
02:36:09 combustible 'ti is based on the total calorific potential of a product I'd have to look up part four sorry I haven't I'm happy to if you want me to do that do you agree in general terms
02:36:20 do that do you agree in general terms that there is a distinction between combust ability and flammability I'd have to look up the diet notion of flour Leslie okay let's just look at fire
02:36:32 Leslie okay let's just look at fire reentry for a moment and it's your position that the external fire then led to fire being able to re-enter on
02:36:44 to fire being able to re-enter on multiple floors I'm sorry can you just repeat that it's a very simple question yeah the answer is probably obvious but your position is that the external fire led to fire being able to re-enter on multiple floors oh yes
02:36:57 multiple floors oh yes and do you agree that the physical evidence would suggest that the extractor fan and the the the small infill panel around the extractor fan was particularly vulnerable in that respect yes I yes I do
02:37:10 respect yes I yes I do in Section 7.4 of his report professor Bisbee's drawn attention for example to the large number of witnesses he comments specifically on early failure ignition of those extract fan units and
02:37:22 ignition of those extract fan units and the supporting and surrounding XPS panels as a route for ingress do you know I do agree and I observed that myself yes yes and he also observes that
02:37:33 myself yes yes and he also observes that many of these were in the flat sixes on the east face that's highlighted in his analysis do you agree I do do you think that this evidence is significant in terms of the reach of fire spread back into apartments I think it I think it is
02:37:48 into apartments I think it I think it is a route into an apartment on it is therefore significant yep but it's one of one of many rather than the only so you would agree with professor torero I think he said that there are a number of
02:38:00 think he said that there are a number of routes back in through the window whether by the side by a glazing phone exactly by the extractor fan going exactly an open window exactly yeah so there all routes back in there all routes back in yeah but I understand
02:38:13 routes back in yeah but I understand that there's a lot of Resident evidence about particularly the extractor fan location yeah yeah and do you think there's any significance in terms of the timing when they're seeing that extractor fan unit go in terms of how
02:38:26 extractor fan unit go in terms of how quickly the window may be failing based on your I don't I'm not sure I'm not sure the context of that sorry Jimmy but as distinct for example from glazing
02:38:38 as distinct for example from glazing failure do you think that that weakness may have meant that the windows had a propensity to fail Oh before the glass quicker than the glass breaks oh is that something you've considered no I
02:38:50 something you've considered no I wouldn't consider that now yep
02:38:56 yes now I think we mentioned this earlier and I just want to take you to it you've identified another potential means by which the windows could have facilitated fire re-entry and spread at
02:39:08 facilitated fire re-entry and spread at the four corners and I think you wanted to go to this so this is figure ten point two point one BL as50 Sten at zero zero twenty one can we go to that figure
02:39:20 zero twenty one can we go to that figure oh yeah so yeah I think you were trying you were mentioning this earlier and you have a concern is this right about a potential flame spread route at the column yeah so it called a column yes so
02:39:32 column yeah so it called a column yes so it's not again just to be clear it's not up like some particular concern I just was you know I'm just trying to find all the pathways so in this condition here this is the kind of rectangular clouding
02:39:45 this is the kind of rectangular clouding of one of the coroner columns so it's a different detail so you actually have two noses okay as opposed to the one
02:39:56 two noses okay as opposed to the one nose I think professor busy week was talking about it later and you know you can think about the fire spreading through the cavity in that column or
02:40:07 through the cavity in that column or actually just simply from one went through one window to the next I'm you know I was just trying to show that it can go both ways depending on the heating condition yeah but it's not
02:40:19 heating condition yeah but it's not meant to be a very serious concern that I have relatively speaking yeah okay I'm now going to turn to some of the matters set out in section 11 of your report
02:40:32 set out in section 11 of your report where you've looked at the the cladding against the B for requirement in the building regulations and just to be clear on your position your position on the cladding system is that you have in
02:40:43 the cladding system is that you have in this phase one report carried out an assessment the compliance of that system with the technical requirements of beef four of the building regulations 2010 is that correct that's correct and distance
02:40:54 that correct that's correct and distance remind ourselves before is the requirement that deals with the prevention of external fire spread it's a functional requirement and it says this the external walls of the building to adequately resist the spread of fire
02:41:07 to adequately resist the spread of fire over the walls from one building to another having regard to the use and position of the building is that correct that's correct now a proof document B itself in visitors two means of compliance either
02:41:18 visitors two means of compliance either a large scale test or I've called the prescriptive route as between twelve point six and twelve point nine F there
02:41:29 point six and twelve point nine F there yep a DB would you broadly agree with that so I'm not I'm not going to use the word prescriptive okay okay so there there's two routes set out and twelve point five using an eight four one four
02:41:41 point five using an eight four one four test where does that large scale or not is another discussion okay yeah so BSA four one four test or there's a statutory guidance given for the individual certain individual components
02:41:53 individual certain individual components in an external wall from twelve point six on and just to be clear have you seen any evidence that there was a b bs April one for test carried out in relation to the specific materials at
02:42:05 relation to the specific materials at Grenville tower specifically for Granville tower Oh specifically far grandpa tire I haven't been given any such evidence or any desktop study specifically for Grandville tower no I
02:42:16 specifically for Grandville tower no I haven't found any particular mention after Cloudant yeah can we just be clear what a desktop study is is it basically an extrapolation of other tests that are
02:42:29 extrapolation of other tests that are then extrapolated three to a different set of materials and a different configuration and conclusions drawn as to performance on that basis is that a fair summary
02:42:40 fair summary it depends who's doing the desktop assessment and I really don't want to talk about that now okay so we'll get onto all of those issues and Phase two so there's rules about how they should
02:42:53 so there's rules about how they should be done and then there is how they are done yeah but in general terms would you agree me it's an extrapolation it's a an analysis it's not a it's not another test oh no no it's it's a it's a paper
02:43:06 test oh no no it's it's a it's a paper exercise rather than a lab you know a fire lab exercise yep and is it your position that if you're using the route in approved document b
02:43:18 using the route in approved document b at twelve point six to twelve point nine and that the construction years must be proven to comply by test evidence that's your position yes well yeah so that's
02:43:30 your position yes well yeah so that's not my position but it's the recession of the statutory guidance document it's a today very clearly in Appendix A of a puka for any construction products and I have relied on that position and I agree
02:43:42 have relied on that position and I agree with it yeah and and is it your general position again we're going to come to each of the specific materials in a moment that such test evidence so as to
02:43:53 moment that such test evidence so as to prove compliance with that route was not available in terms of the materials which were selected that's correct and is it correct having examined each of the available test evidence for each
02:44:06 of the available test evidence for each element that you find each to be non-compliant with the B for requirement that's correct is another way of looking at it simply to examine the physical evidence of the fire spread and assess that against the
02:44:17 fire spread and assess that against the functional requirement as in what we saw in the videos and the footage oh I think that displays quite categorically that the external law did not adequately
02:44:28 the external law did not adequately resist the spread of fire yeah so that's my next position is it your position that the entire building envelope system did not adequately resist the spread of fire over the walls having regard to the height ye stand position of the building
02:44:39 height ye stand position of the building and so was not compliant with B for daddy is my position yes
02:44:47 and you're completing just for the note is set out two point nine point six and your conclusions and two point nine point eight I don't think we actually
02:45:00 point eight I don't think we actually need to go to that now so I want to turn to look at each element of the the cladding system the rainscreen cladding
02:45:11 cladding system the rainscreen cladding panels on the columns and the spandrels were Reina bond 55 PE silver metallic manufactured by a conic is that correct
02:45:22 manufactured by a conic is that correct yep yes and your position is these should have been national class north throughout or European class bs3 d2 or
02:45:34 throughout or European class bs3 d2 or better is that correct yes our set out and diagram for - yes so that's twelve point six of a pleat document B diagram forty you have that correct and your evidence is that these Reina bond PE
02:45:46 evidence is that these Reina bond PE fifty-five cladding panels did not have such certification certificates by the class naught or Class B or better yeah I haven't provided with any relevant test
02:45:57 haven't provided with any relevant test evidence for ran of 155 PE that has a performance of either Class B or class naught now it's right that no riveted
02:46:09 naught now it's right that no riveted panels were used at ground floor tower is that right there with a cassette system that's correct and and we'll come back in a moment we're going to look at a couple of diagrams that help us about the difference between a riveted and a
02:46:20 the difference between a riveted and a cassette system yeah so we'll come back to them in a moment is it is it right that the certificates that you have seen confirm that the rain upon 55 PE 55 cassette system is a European class II
02:46:33 cassette system is a European class II is that correct that's correct yeah that's just for the know that's paragraph eleven point six point ten of your report from page 19 of chapter 11
02:46:46 yeah and is it also relevant to note I think you note this in your report that this class II rating was dependent upon the panels being installed with a class a 2 or better substrate is that right
02:46:59 a 2 or better substrate is that right yeah that's correct because after tests carried out of the CTE ask TB yeah and just to be cleared by that do you mean that the installation it was tested with with Class A 2 or better I mean the
02:47:12 with Class A 2 or better I mean the substrate so the the material behind the Rena bond in that test had an A to E
02:47:23 Rena bond in that test had an A to E realtor which it's affixed yeah well
02:47:28 this is paragraph 11 I would now take out the test report if I was in the Army I'd show you some photos so in in the test and France it is actually a fixed
02:47:39 test and France it is actually a fixed on to what I think is a plaster board okay we're not talking about another material some distance behind exactly
02:47:51 material some distance behind exactly we're talking about what it's fixed it exactly so the in in that test don't imagine the panel air not a big piece of insulation and a wall that's
02:48:02 piece of insulation and a wall that's not what that test does it's a panel attached on to in this particular case one layer of a material to look at the panel on its own in a particular fire
02:48:13 panel on its own in a particular fire time and we'll come to it in the next topic but a Grenville tower the insulation was predominately Class D Celotex insulation is that correct that's correct yes yeah yeah and is your
02:48:25 that's correct yes yeah yeah and is your V that absent a valid applicable certificate there's no proof that the product complied with the guidance in ADB is that correct there's no proof it just doesn't comply yeah because there that evidence isn't available yep and
02:48:39 that evidence isn't available yep and just a point of detail and again we may need to get into this more at Phase two you've found that the silver metallic it so you found the silver metallic panels had Bay's a black core and a translucent
02:48:51 had Bay's a black core and a translucent core on-site is that right yes so yes that's correct that both types appear to have been present our grand full terror yeah yeah and you say that they achieve
02:49:03 yeah yeah and you say that they achieve different test results to be Sen one three eight two three yeah you've said that they both achieve the same reaction to fire test rating sorry different test
02:49:15 to fire test rating sorry different test results to that standard but then they both achieve the same reaction to fire test rating is that correct and you just take authority over your clas five zeros 11 at pages 18 to 19 paragraphs eleven
02:49:30 11 at pages 18 to 19 paragraphs eleven point six point nine and eleven point six point ten you just focus in on eleven point six point nine at the bottom so you note yeah they've either
02:49:47 bottom so you note yeah they've either got a black or translucent core yeah and then if we can go over the page you know to different core tight yeah she different test results but you note that
02:49:58 different test results but you note that both core types are classified with one reaction to fire performance can you just explain to us why you were interested in that well I was just pointing out that for a
02:50:10 well I was just pointing out that for a while they seemed to pick the lower performance when they issue the classification report right okay yep
02:50:22 now in your original report of April 2018 you explained that you did not accept a 2008 British Board of a grant be be a certificate as valid for the
02:50:33 be be a certificate as valid for the cassette system although you did accept at that time it might be valid for the rivetted system is that correct
02:50:41 no no it is I'm sorry no it's not now but in your original report you said you certainly wouldn't accept it as valid for the cassette system but you didn't yet give detailed reasons we now know I
02:50:53 yet give detailed reasons we now know I don't you know is it right that in your most recent report you've expanded on the reasons why you don't think that 2008 BBA certificate is valid for the cassette system yes that's correct yeah and that very detailed analysis I'm
02:51:07 yeah and that very detailed analysis I'm not going to take you to all the detail it's there at paragraph eleven point eight of your report and in appendix o specifically is that right that's where we see the detail yeah yeah yeah I do
02:51:19 we see the detail yeah yeah yeah I do just want to look at the certificate and just get you to highlight a few of the very key point yeah I can I just say we're in a very important and complex subject now and I'm getting really tired
02:51:30 subject now and I'm getting really tired so I think pretty soon I'd need a break because I want to give the BBA cert it's good service while you're rapidly asking me all these questions at the moment yeah big questions coming very fast I'm
02:51:46 yeah big questions coming very fast I'm happy to answer that question but just they're very complex questions and I can't move the ugly as you are at the end they will be like simple questions yeah okay so just ask me that question
02:51:58 yeah okay so just ask me that question again the BBA yeah I mean it's a big subject yeah yeah cuz I was going to go to the certificate and then we can take our time over it if we do it after lunch yeah yeah I don't think you yes that's
02:52:12 yeah yeah I don't think you yes that's right yeah we're never right now it's not okay yeah really employers yeah yeah just we'll have a break now into a corset of to
02:52:23 have a break now into a corset of to okay don't talk to an on the evidence when you're right will break down and
02:52:43 when you're right will break down and resume a quarter to two please thank you