Expert architect Paul Hyatt provides technical evidence on Celotex RS5000 insulation product literature, cavity barrier strategies, and compliance with Building Regulations Approved Document B.
00:00:14 so good morning everyone welcome to today's hearing
00:00:19 hearing we're going to continue hearing evidence from mr paul hyatt so perhaps you'd ask mr hyatt to come in please would you
00:00:38 good morning mr hyatt morning
00:00:43 ready for another day's answering questions yes sir thank you very much right just a minute off you go thank you mr chairman good morning mr hyatt good morning um i want to turn back to the topic please of insulation and
00:00:55 topic please of insulation and specifically celetex rs 5000 could we please turn to cel
00:01:02 cel 50416
00:01:05 50416 this is the rain screen cladding compliance guide which was published in february 2015 as i think you'll be able to see if we go to page five
00:01:16 go to page five if we can go to page five um you can see the date
00:01:19 the date um
00:01:23 on that page page five please uh in fact you can't i think quite but it doesn't matter it is actually dated that day now go back to page one please if we can go back to page one um you can
00:01:34 if we can go back to page one um you can see that it is four specifying celetex rs 5000 in buildings above 18
00:01:39 above 18 meters and if you go to page the next page page two please
00:01:52 that uh says at the very top this document provides guidance on complying with approved document b2 adb2 for external wall clouding systems fixed to steel frame or masonry constructions
00:02:03 to steel frame or masonry constructions that provides a step-by-step guide to an alternative route to compliance for adb b2 through meeting the performance criteria set out in br135 through testing to bs a414 2002
00:02:16 through testing to bs a414 2002 or bs 84142 2005. um just there do you think that in this respect the guide has made a distinction
00:02:27 a distinction between the linear route to compliance with adb
00:02:31 with adb and the alternative route to compliance through meeting the performance criteria set out in br135 through a test a full-scale test i i was thinking that
00:02:42 thinking that um just as you were formulating the question
00:02:46 question it isn't as clear as it should be in what respect is it not as clear as it should be do you think um it provides a step-by-step guide to an alternative route to compliance for adb2
00:03:02 um
00:03:08 document finds a guidance
00:03:21 i i think i've got to read it twice or three times myself and i still wouldn't get quite to grips with this i think i'd be turning and asking for for help but um
00:03:34 turning and asking for for help but um um perhaps i can try the question a different way we're looking at that little paragraph i've just read to you putting yourself in the shoes as you're of course asked to do so of the reasonably competent architect
00:03:46 the reasonably competent architect would the reasonably competent architect look at that and think to themselves well this compliance guide is telling me that the
00:03:57 product complies with approved document b2
00:04:02 b2 that is so but because it does so because
00:04:05 because or it meets the alternative route for compliance through meeting the performance criteria set out in br 135. well that was the way i took your question and i took the question does it make it absolutely distinctly clear that it is
00:04:17 absolutely distinctly clear that it is the alternative route i suppose it says alternative route there actually um yes yeah um and to put the question another way around would the reasonably competent architect
00:04:28 would the reasonably competent architect looking at that if they did look at it think to themselves ah well this is not a material which is of limited combustibility and therefore can be used
00:04:39 be used in satisfaction of the linear route to compliance
00:04:51 i don't know
00:04:55 it's very difficult for me to answer this question i think i would take comfort that this is telling me that it complies with adb2 i don't know
00:05:06 that it complies with adb2 i don't know if i'd
00:05:06 if i'd actually interrogated that further there's the compliance can we then go to page three
00:05:18 and on the right hand side of that page towards the top you can see a column
00:05:25 column and three bullet points or little arrows and then underneath those arrows it says the classification applies only to the system as tested and detailed in the classification report
00:05:37 detailed in the classification report the classification report can only cover the details of the system as tested it cannot state what is not covered when specifying or checking a system it is important to check that the classification documents cover
00:05:48 that the classification documents cover the end use application well that's absolutely clear i was going to ask you that's absolutely clear right may i just make the point the timing of all this of course is very late
00:05:57 late because this document was not available i think at the time that this product was first uh proposed
00:06:05 proposed that is that is correct so this would an an architect who's adopted this product earlier on would not necessarily be revisiting the whole of this conversation
00:06:16 whole of this conversation that that is correct but i want to what i want to do is to show you all three pieces of manufacturer's literature on rs5000
00:06:24 rs5000 this is the latest one we're starting with you're absolutely right if we go to page four of this document again it says in the right-hand column uh in the second paragraph the fire
00:06:36 uh in the second paragraph the fire performance and classification report issued only relates to the components detailed and constructed in figure four any changes to the components listed in construction methods set out in figure four
00:06:46 four will need to be considered by the building designer and the figure 4 is set out below it and you can see the ingredients or the elements of the cladding system which was tested
00:06:58 cladding system which was tested under a bs-8414 and if you look above the diagram to the middle column there's a little heading the system
00:07:11 there's a little heading the system tested was as follows in bold and you can see that there are six elements to that uh starting with 12 millimeter fiber cement panels just looking at that um again from the
00:07:23 just looking at that um again from the perspective of the reasonably competent architect is there anything misleading or
00:07:27 or unfairly presented in either in this page either in the right hand column or the left hand column i've shown you the middle column actually no i've seen this before and it's
00:07:38 i've seen this before and it's absolutely clear to me that this is not the arrangement and to which the celotex was put on the building and that would be clear to an architect looking at this thank you let's next go please to cel
00:07:53 thank you let's next go please to cel 6013
00:07:55 6013 this is the rain screen cladding specification guide uh also produced by celetex but this time in august 2014 excuse me mr minute it would also be clear
00:08:06 be clear to an architect even before reading that that any
00:08:10 that any test any alternative route that involved a test
00:08:13 a test that test would have to be precisely as per the building would you say the test would have to be precisely as per the building do you mean that the elements yes and the design of the elements
00:08:25 yes and the design of the elements hanging together correct would have to be precisely as proposed for the building yes and any deviation from that requires specialist advice thank you now let's look at this document this is
00:08:37 now let's look at this document this is as i say dated august 2014 it's called the rain screen cladding specification guide as you can see there if we go to page five please we can see on the right hand side
00:08:50 we can see on the right hand side of the page a third paragraph down the fire performance and classification report for celetex rs 5000 only relates to the components detailed above any
00:09:02 to the components detailed above any changes to the components listed will need to be considered by the building designer and then if you look at
00:09:08 at the left-hand side of the page you can see rather more information under fire performance in big red letters
00:09:15 letters it says uh brain screen insulation celetex rs-5000 is class naught fire related fire rated as described by national building regulations and then below that it says
00:09:27 regulations and then below that it says building above 18 meters celetex rs 5000 has been successfully tested to bs 84142 of 2005. fire performance of external clouding systems
00:09:38 clouding systems test method etc meets the criteria set out
00:09:41 out in br 135 and is therefore acceptable for use in buildings above 18 meters in height
00:09:47 height and note the word therefore there the system tested to be s8414 to 2005 was as follows and there again you've got the
00:09:58 you've got the six elements of the test
00:10:03 again on that document from the perspective of the reasonably competent architect
00:10:07 architect is there anything misleading or or unfairly presented about uh the use or potential use of this material on
00:10:18 use or potential use of this material on a building above 18 meters i think so i i i've looked at this before
00:10:23 before and the word therefore um is a problem for me because the clear implication of that is that this product is okay
00:10:34 is okay for buildings of over 18 meters it's then qualified by a specific test i think the manufa i believe the manufacturers should make it abundantly clear that
00:10:46 should make it abundantly clear that that their product
00:10:51 should be scrutinized with the greatest of care
00:10:54 of care for use this manufacturer should make it clear that this product should be scrutinized with the greatest of care situations over 18 meters um i don't think it's as clear as it
00:11:06 um i don't think it's as clear as it should be
00:11:09 well i note that if i were to put celetex's position to you
00:11:16 you i would be saying to you that it is clear because uh although it says that it can be used above
00:11:24 above in buildings above 18 meters in height it then goes on to make it clear in the right hand columns i've shown you that the file performance and classification report only relates to the components detailed above
00:11:35 the components detailed above any changes to the components listed will need to be considered by the building designer and celetex would ask well what's not clear about that
00:11:45 well it would be good if it said it it uh um
00:11:48 uh um statistics being successfully tested that adapted to that and is therefore acceptable for using buildings above 80 meters tonight provided and then it could be absolutely clear provided there's no provided about this i see
00:12:01 there's no provided about this i see before we leave this document can i ask you to turn to page
00:12:11 to page uh we'll stay on the same page and actually look at the top left hand corner where it says in big red letters celetex rs 5000 has been successfully tested to bs
00:12:23 has been successfully tested to bs 2005 performance of external cladding systems just taking that on its own if that's all you were to look at given that that's been highlighted is there anything unclear incomplete or
00:12:34 is there anything unclear incomplete or potentially misleading about that
00:12:42 um no um but we're we're certainly at the edges in all this the moment that the product the moment that the
00:12:54 that the product the moment that the architect is departing from clear compliance with the linear route in adb2 i think specialist advice is needed finally can we look at cel40s1240
00:13:08 finally can we look at cel40s1240 please this is the celetex rs 5000 product data sheet and it's dated the first of august 2014.
00:13:19 dated the first of august 2014. first can i just ask you to look please at the big pink banner at the head of page one where it says celetex rs 5000 premium rain screen cladding board
00:13:32 premium rain screen cladding board brackets suitable for buildings above 18 meters in height close bracket what would a reasonably competent architect take from that well that goes to the
00:13:44 take from that well that goes to the point i was making perhaps not as eloquently as i should have earlier which is that there's no qualification to this and then if we so i beg your pardon do continue
00:13:55 continue no it's my fault i paused there's no qualification to it and so i think the architect can take comfort from it may take comfort from it now it can be argued that
00:14:06 argued that the arctic should look further and harder but i believe that celetex all manufacturers have a duty particularly in relation to issues like fire to make sure that every assistance
00:14:17 fire to make sure that every assistance is given
00:14:18 is given to those who will be specifying and making the right decisions and this is clearly mis i think that the the potential here is for this to be misunderstood and manufacturers should not
00:14:31 should do their best to avoid that
00:14:36 do you think the competent architect would read this as if it said generally suitable
00:14:42 suitable as opposed to suitable in specifically tested circumstances no i think generally suitable suitable for buildings above 18 meters in height so it's not it's not qualified
00:14:57 i i'd like to put it if i may into another context as well i've mentioned in my report the dangers of condensing i'd use the word crushing decision making into such a short time
00:15:11 decision making into such a short time when i began my career it's not a history
00:15:14 history uh lesson but when i began my career the process of developing a design and specification was very orderly and took longer or more time was given up front we now
00:15:26 or more time was given up front we now have a situation through design and build where there is disorder i've made that clear in my report where later stages can be done before earlier stages the presumption would have been that they would have
00:15:37 would have been that they would have been done
00:15:38 been done earlier so an architect can end up in a situation where there's an immense crushing of time and it's it's uh i'm i've got to be careful the way i describe this but satcher
00:15:50 describe this but satcher being presented with this it's very easy to say
00:15:53 to say for me to think yes everything here should be read in a very orderly fashion but if the architect's trying to deal with the interior of the building trying to deal with the cladding trying to deal with a range of components going
00:16:05 to deal with a range of components going into the cladding there's sudden late changes coming in from the design build contractor then there will be limited amount of time that can be spent and
00:16:15 and it's for that reason it's very important i think that the design team are assisted by the those who certify and those who manufacture with information which is clear in the interests of not having terrible
00:16:28 in the interests of not having terrible outcomes
00:16:30 outcomes thank you now i'm going to show you one or two
00:16:34 or two further parts of the document before i do that and while i'm on page one here you can see that in the first part of the page
00:16:45 the page first part of the text on that page there are five bullet points underneath the sentence with celetex rs 5000 you are specifying an insulation board vert
00:16:56 board vert and then the third bullet point says has class naught fire performance and then it says throughout the entire product in accordance with bs 476
00:17:07 accordance with bs 476 can you help us uh with what a reasonably competent architect let's say reasonably familiar with approved document b would understand by that sentence
00:17:28 an intensity of spotlight has been placed on
00:17:31 placed on on these words and terms at that time i think an architect would have just taken it as a simple of most architects i think not can't speak for everyone but most artists
00:17:42 speak for everyone but most artists would have taken it as a simple assurance that the product meets
00:17:46 meets class o in its entirety full stop it's okay
00:17:50 okay what does throughout the entire product mean in the context of having a class naught fire performance well we've got the surface and we've got the the remainder of it
00:18:01 and we've got the the remainder of it um in in so far as um this is cons this node is concerned it seems to suggest that the entire product right through its
00:18:12 the entire product right through its depth carries that qualification
00:18:19 is that comprehensible
00:18:23 uh when it's when it's dissected probably not because classo is to do with a surface spread of flame um but it certainly seems to give an assurance
00:18:35 assurance to me it almost gives an assurance beyond a surface spread of flame but scrutiny investigation would suggest that that's not going to be likely is the reference to class naught there
00:18:49 is the reference to class naught there opposite in the context of what then follows namely fire performance through the entire product no can we then just turn on in the document
00:19:01 document again it's misleading i think yes thank you
00:19:04 you can we turn on in the document to um page three please uh we can skip page two
00:19:11 two straight to page three where you can see there it says uh under the uh list uh where you've got the list again of co of components the fire performance and classification
00:19:23 the fire performance and classification report issued only relates to the components detailed above any changes to the components listed will need to be considered by the building designer you can see that yes and you can see the test the system tested again from the
00:19:35 test the system tested again from the perspective of the reasonably competent architect
00:19:39 architect is there anything misleading or unfairly presented about that statement or sentence in its
00:19:50 context well no i i can't add any more to what i said um
00:19:57 said um earlier except for i would just ask i've looked at this document before but i don't remember is that pink banner across every page of the document uh it's certainly you're right it's on page three if we flip back to page two
00:20:11 page three if we flip back to page two it is also there so i think the answer and how many pages does the document have sue well let's look on uh let's look onto page uh i'm not sure there is a page four
00:20:22 there is a page four they're asking me a question which electronically i'm not able to answer um but every page we've seen it's got that banner on the top yes and so certainly that's right it seems to me to be reinforcing
00:20:34 to me to be reinforcing there isn't a page four i can tell you so every page well the the flag line of this seems to be reinforcing at every point that this is a product suitable
00:20:45 is a product suitable about 18 meters in height i i understand the
00:20:48 the the qualification i can't add anymore to what i said before yes
00:20:56 uh can i ask you to go then back to your report your supplemental report please at
00:21:02 at p h y s six zeros two and i'd like to start at page fifty please just to give you the context and let's look at paragraph two point five point five there
00:21:18 uh which you're talking here about uh the studio e's opening statement placing heavy emphasis on its entitlement to rely on the advice and expertise of others
00:21:31 in this respect it mentions within these paragraphs max fordham x over ryden harley and celetex of particular importance is studio e statement of paragraph 12.17 which i quote as follows studio e relied
00:21:43 which i quote as follows studio e relied on the advice of the appointed specialists and suppliers that the products being considered was suitable for the intended purpose and studio he considers it was reasonable and appropriate for it to do so and then if we turn the page
00:21:54 if we turn the page page 51 we can see what you say paragraph 2.5.6 you say this whilst i fully understand that construction involves teamwork between both individuals within companies and across different companies
00:22:06 companies and across different companies that are independently appointed in my opinion an architect cannot in circumstances of failure offer as mitigation the fact that he stroked she had relied upon and indeed accepted the
00:22:18 had relied upon and indeed accepted the advice of others where that architect should either have known or routinely discovered through research and or interrogation that such information or advice was wrong
00:22:27 wrong now just taking that paragraph and applying what you say there to these three celetex pieces of product literature about rs 5000
00:22:38 literature about rs 5000 what approach do you say an architect a reasonably competent architect should have taken to those pieces of literature
00:22:50 well i i go back to earlier comments i think during this examination i think that the architect um should have known that they're going
00:23:01 um should have known that they're going down the linear route 12 7 is paragraph 12.7 of adb adb a b proved document b
00:23:12 adb a b proved document b 2 is absolutely clear limited combustibility is required
00:23:18 therefore the architect should be taking great care to make sure components in are going into the building of limited combustibility so that the starting point should be that
00:23:29 starting point should be that expectation right and when you say they're routinely discovered through research and or interrogation are you saying that the reasonably competent architect should have
00:23:41 competent architect should have interrogated each of these three pieces of product literature in relation to rs-5000
00:23:49 i i i think that is correct i i but i don't in any way want to diminish the criticism i make
00:24:01 want to diminish the criticism i make of celetex is documentation or others who should have known better who were involved as part of the design team that that is
00:24:12 as part of the design team that that is all
00:24:12 all clearly that's all my view but at the same time
00:24:17 same time i the architect i think should have known
00:24:20 known that this that the insulation must be so compliant and should have taken care
00:24:27 care to even receive robust assurances from others
00:24:32 others or alternatively satisfy themselves through
00:24:35 through the most careful scrutiny of the documentation but it's a difficult territory
00:24:41 do you take the view that the celetex rs 5000 product literature red as a whole makes it clear reasonably or
00:24:52 makes it clear reasonably or sufficiently clear to the reasonably competent architect that the fire performance and classification data relates only to the system tested in its exact components and set up and that any
00:25:05 components and set up and that any changes to the components and construction method would need to be considered by the building display that is that is the case it does make it clear
00:25:14 clear but but i think it demands more more scrutiny and attention than it should because i believe it i think that document sets out to
00:25:25 think that document sets out to mislead actually in what way exactly well because it's it's it's carrying the banner across it the presumption is that the product is compliant and the the specifier
00:25:37 is compliant and the the specifier has to interrogate the literature to discover that actually there are inconsistencies therefore is missing there's no um qualification made early on which should
00:25:49 qualification made early on which should be there in my opinion so yes when the architect when the specifier studies the document fully it should anybody specifying should be able to read that document
00:26:00 should be able to read that document that's clear and on reading that document they should make the conclusion that it is not appropriate that is clear i don't think that
00:26:08 that it's responsible of a manufacturer to make that such a hard to make that such heavy going such hard work
00:26:18 work but it should have been clear you see it should have been clear but you also say that it was clear to the reasonably competent architect i'm just trying to that's my my zap just where the line exactly should fall
00:26:29 where the line exactly should fall yes well i understand and i i have to say that the it it it should be clear to a accomplish
00:26:40 it it should be clear to a accomplish the architect should have read it and it should be clear the arctic should have read it and the competitive architect would have understood it
00:26:50 well i think what you're saying then is that the competent architect should have read it with sufficient care to understand the limitations imposed by the nature of the test which
00:27:01 imposed by the nature of the test which is being relied on but the manufacturer set out to make it difficult for him to do that is that broadly thank you yes
00:27:12 is that broadly thank you yes um i i can't others will interrogate the manufacturers to what they were doing but it's certainly not it's i believe that
00:27:23 they should have spelled it out clearly absolutely the case yeah i see thank you for that just just to pick you up on one
00:27:33 uh way of putting it put to you by the by the chairman the manufacturer set out to make it difficult whether or not the manufacturer intended subjectively to do that do you agree
00:27:44 subjectively to do that do you agree that
00:27:44 that the objective effect of what the manufacturer did made it difficult for him to do that for the reasonable architect to yes interrogate yes um
00:27:55 to yes interrogate yes um can i just then ask you to look at dr lane's view about this which is it blas four zero i'm sorry five zeros twenty six
00:28:05 blas five zeros twenty six of page twenty five this is paragraph e four point one point six of her report
00:28:16 point one point six of her report and she says here i've also explained my opinion that any difference between the grenfell tower rainscreen cladding and the system tested in the relevant supporting fire test evidence
00:28:28 means that test evidence cannot be relied upon to demonstrate compliance with the provisions made in section 12 of the adb 2013 and particularly if no other supporting evidence is provided
00:28:39 evidence is provided do you agree with that view yes uh and uh she also says uh in the same document of page 34 if we could
00:28:50 the same document of page 34 if we could move on
00:28:50 move on a few pages to page 34 please so could i just go back to that again and just read it again yes of course go back to page 25
00:29:01 yes yes you agree with that yes yes
00:29:12 yes yes you agree with that yes yes thank you can we then move um uh to page 34 where she says at um e 4 3 8 and also table e6
00:29:24 3 8 and also table e6 she says this test report does not therefore does not classify the inspected as built grenfell tower rain screen cladding system it cannot therefore be relied on
00:29:36 system it cannot therefore be relied on to demonstrate compliance with the provisions made in section 12.5 of the adb 2013. you see that yes you agree with that yes yes
00:29:52 and if we go on to uh the next uh paragraph down she says further it cannot be relied upon to demonstrate that the external wall at grenfell tower meets the functional requirement of b4
00:30:03 meets the functional requirement of b4 of the building regulations do you agree with that yes
00:30:11 does that lead to this conclusion in your opinion mr hyatt that studio e uh if if they had been acting as the reasonably competent architect
00:30:22 reasonably competent architect should not or would not have allowed celetex rs 5000 to be specified or installed
00:30:27 installed as part of the rainscreen clouding system at grenfell tower because the components of that system differed from that described as having been tested to meet the performance criteria in br135
00:30:39 performance criteria in br135 that that i i agree that and that's consistent with what i've said in the report
00:30:43 report do you also think that further testing or a desktop study or perhaps a holistic fire engineering report should have been commissioned in order to be able to assess the rain
00:30:54 in order to be able to assess the rain screen cladding that was to be specified for installation
00:30:59 yeah if they were yes if they when they were going to use it yes and that means that there was as things stood as this right no basis or no reasonable basis upon which studio
00:31:11 or no reasonable basis upon which studio we could reasonably have concluded that the rain screen clouding system as specified and installed at grenfell tower was compliant no i don't think that they could have i agree with that um
00:31:23 i would have not bothered with any testing
00:31:26 testing time wouldn't have allowed it time would not have allowed it and i would have realized that um it's a non-starter but there we go and to the extent that is this right to the extent that studio e was seeking to
00:31:37 the extent that studio e was seeking to rely on other design and construction professionals working on the grenfell tower project they were unreasonable in doing so in relation to the celetex material the cellotex product
00:31:55 well um i think they've got good reason to be i said this yesterday uh they've got good reason to be more than unhappy
00:32:06 than unhappy that they've been uh i used to term fed a curveball had max fordham's suggest a material which clearly was unlikely to comply that's the first
00:32:18 was unlikely to comply that's the first point and i think that they've got more every reason to be very unhappy with vex over for not having pointed it out having received the stage c and stage d reports that's all true but that doesn't
00:32:32 reports that's all true but that doesn't uh exonerate um studio e in my opinion now we talked about the differences between the system installed and the system
00:32:39 system as described in the celotex literature as having been subjected to a bs-8414 test to meet the br 135 criteria
00:32:50 criteria do you agree that those systems were mutually completely different yes and just to finalize on this point while we've got page 34 of uh of dr lane's report up
00:33:01 page 34 of uh of dr lane's report up here on the page sorry that's the system that was in the test against the system that's been installed yes yes absolutely yes absolutely yeah and just to round off on this point
00:33:13 and just to round off on this point while we've got this page in front of us could you please look at e 4 3 6 e
00:33:18 e 4 3 6 e 4 0. 3.6 at the top of page 34 of dr lane's report she says there i conclude from my comparison that there are multiple diff significant
00:33:29 that there are multiple diff significant differences between the rain screen system
00:33:31 system tested in bs 84142 2005 and she describes the title of that produced by bre global on the 1st of august 2014 and bs 84141
00:33:43 of august 2014 and bs 84141 2015 and a1 2017 test on a ventilated mali eternity rain screen system with celetex rs 5000 insulation on the 30th of april 2018
00:33:55 30th of april 2018 when compared with the as-built grenfell tower construction um to the extent that you're familiar with what she's referring to there would you agree with it absolutely
00:34:15 [Applause] can we then turn to the subject of window infill panels um
00:34:26 window infill panels um when i say window infill panels i know that you know what i'm talking about from your demonstration in your model every changing topic i'm going to ask if i could take my jacket up of course you may yes thank you
00:34:45 okay right um is it your opinion that paragraph 12.7 of approved document b applies to products with an insulating core
00:34:56 products with an insulating core such as the window infill panels yes i've made that clear in the report and is it your view that when the window infill panels constituted a part of the external wall construction rather than
00:35:07 external wall construction rather than the window i believe that to be the case i think others could take a different view but i believe it is let's just look at the nbs specification sca
00:35:19 nbs specification sca 50169 please and i'd like to take you to page 145
00:35:24 page 145 in that document [Music]
00:35:28 [Music] this is l10 which is described as windows stroke roof light stroke screen stroke louvers and i'd like to show you paragraph 332
00:35:39 and i'd like to show you paragraph 332 at the top of the page aluminium windows fixed unit aluminium and then about a third of the way down you'll see the second bullet point do you see it says panel stroke facing type
00:35:50 you see it says panel stroke facing type aluminium faced insulated panel comprising core insulation aluminium lining panel and integrated channel profile around perimeter fully air sealed at edges
00:36:01 perimeter fully air sealed at edges to achieve minimum u-value of 0.15 yes i've seen that given that that is in the nbs specification for uh window infill panels at the
00:36:15 for uh window infill panels at the windows part of the specification how can you explain why you say it's actually part of the external wall rather than part of the the windows
00:36:28 big um interesting question i hadn't thought of it that way before the
00:36:34 the the um the window the windows in the sense of those parts of let's i'll begin if i may
00:36:45 parts of let's i'll begin if i may with that we've got two columns and between the columns there is what i've described as ribbon window system and that's a fairly
00:36:56 window system and that's a fairly well known term throughout the architectural world of ribbon window system that ribbon window system is a series of windows with glazing in which are fixed into an overall frame i believe that's where
00:37:08 an overall frame i believe that's where it goes
00:37:10 it goes and with within there you can put multiple windows within that framing system they've put a solid infield panel and behind that panel um or they put an infill panel so
00:37:23 panel um or they put an infill panel so an infill panel which
00:37:26 which is not glazed behind that panel there is a section of wall and that is an upstand from the spandrel panel
00:37:35 panel which is uh which was part of the original building uh back built back in the 70s manufactured offside brought to site placed on top of the wall on pins i
00:37:46 placed on top of the wall on pins i suspect and then bolted to the soffit the concrete soffit so
00:37:50 so that part of the ribbon window system crosses a piece of wall i think that my interpretation of that was that
00:37:59 was that that then forms part of the wall of the building it's not it's not a window in that sense now your understanding is you've just explained it to us is that something
00:38:11 explained it to us is that something that would commonly have been understood by the reasonably competent architect at the time of the nba specification
00:38:22 probably not can you give us an insight into
00:38:26 into how common the view was at the time that insulated infill panels such as those which were part of the windows
00:38:40 part of the windows as per the nbs specification should in fact have been treated as part of the external wall construction instead that i'm afraid i cannot do
00:38:49 cannot do because i have absolutely no no basis upon
00:38:53 upon which to give any advice say i've i've not questioned others i've seen no reports about it i've i know of no other circumstances like this
00:39:03 like this other cases like it i have no idea all i can say is that as i came to this um piece of work i interpreted it that way
00:39:15 i interpreted it that way can we go to your supplemental report please at
00:39:19 please at phys 602
00:39:23 phys 602 at page 38 [Music]
00:39:26 [Music] and we have here paragraph 2.3.47 and you say here in the second half of the paragraph five lines down
00:39:39 paragraph five lines down you say therefore a detailed drawing for these elements of the works was required to show the design principles of the envelope to brief the specialist subcontractor for the cladding
00:39:48 cladding and to indicate the arrangements for design of the internal window lining and insulation and packing behind those linings
00:39:55 linings for which the architect was responsible under stages e and f1 for tendering purposes and under stages f2
00:40:02 f2 and k during the post novation period now that's what you say there now in the absence of that detailing design detailed design and as the nbs
00:40:13 design detailed design and as the nbs specification had had shown a pir insulation for use within the external cavity would you think that it was reasonable for a design and build contractor such as ryden
00:40:24 as ryden to adopt the same type of insulation product specified for the external cavity
00:40:29 cavity for use in the internal window linings
00:40:37 i was trying to read the first part of that paragraph as well because i'm sorry it took me at the fifth line sixth line may i read the first part as well yes of course
00:41:04 right could you answer the question again yes please um let me try a slightly different way would you consider it reasonable for a design and build contractor to adopt the same type of insulation product which had been specified for the
00:41:16 product which had been specified for the external cavity uh to be used in the internal window
00:41:28 [Music]
00:41:32 linings i'm not i'm not happy with a contractor drawing his own conclusions as to what can be used where the
00:41:45 as to what can be used where the architect's information with the employer's requirements made reference to a different arrangement for the window linings head jams and sills i think that
00:41:58 and sills i think that a contractor should not presume not make presumptions that arrangements shown elsewhere can be applied
00:42:06 applied there was a significant switch to those linings
00:42:09 linings the plastic sill jams and head that's a very significant switch on its own and then the packing insulation and or filler material
00:42:22 insulation and or filler material because it was functioning in all those ways
00:42:25 ways uh behind it and i i think that it's a significant deviation from the employer's requirements and um authority for one of the better terms should have been thought for that
00:42:37 terms should have been thought for that thank you before we leave this topic let me show you something else within the nbs specification that might give us a clue can we go please to sea 50169 at page 243
00:42:54 if you look at paragraph 235 towards the foot of the page you can see that it says
00:42:58 says compressible insulation in gaps and you can see there that what is specified is rockwool and in the second bullet point specifically
00:43:10 in the second bullet point specifically mineral wool to bs en13162
00:43:16 would that have been a direction given by the reasonably competent architect to the design and build contractor as to
00:43:27 to the design and build contractor as to what should be used uh in the internal linings yes window linings yes yes sir does that mean that in your opinion the
00:43:38 does that mean that in your opinion the reasonably competent architect would have
00:43:39 have expected ryden or the designer bill contractor instead of reaching for the same materials used within the external wall construction instead to have used
00:43:51 wall construction instead to have used rockwell
00:43:52 rockwell in the gaps on the inside of the windows absolutely
00:44:02 i'm not going to turn to a new topic completely which is cavity barriers can i ask you to start please by going to your report at page uh 110 p h y r 5 0 is 28 at page 110
00:44:18 phyr5028 at page 110 and we can see here
00:44:24 you you say at paragraph 3.11.3
00:44:30 and this is in the context of your indicative approach you say for the avoidance of doubt this which is your indicative approach should not be taken as a design that hks architects
00:44:41 architects would adopt now is the indicative approach that you've adopted in relation to cavity barriers an approach that you personally or hks as a firm have ever actually
00:44:53 or hks as a firm have ever actually adopted in practice the exact arrangement that i've developed there no we we haven't had a situation like that and so no we haven't adopted that exact arrangement
00:45:04 haven't adopted that exact arrangement why did you prepare an indicative approach
00:45:08 approach um i i felt that it would be useful to the inquiry
00:45:17 for me to test whether the general approach to the overclouding of the building [Music]
00:45:26 [Music] could have been carried out in a way that was
00:45:28 that was functionally equivalent to the intentions that's the eu value to be achieved uh aesthetically um similar um so i thought it would be
00:45:40 similar um so i thought it would be useful
00:45:40 useful for the inquiry to to see whether that could be achieved and in the doing of that i learned that i was also able to demonstrate
00:45:52 demonstrate the processes that an architect would go through
00:45:56 through typically in solving a problem like this now there's no um cast iron method statement you can't pull a booklet off a shelf that tells you how to do it but as i said yesterday
00:46:08 you how to do it but as i said yesterday or the day before maybe we're problem solvers
00:46:11 solvers we face a new problem and every building is a prototype actually that's almost true occasionally get repetition but almost every building is a prototype this was a prototype um they're facing
00:46:24 this was a prototype um they're facing this
00:46:24 this it's a bespoke design and so they're going to piece this whole thing together
00:46:31 together and it seemed to me that if i did an indicative scheme i would show how close it would have been possible to get the overall solution
00:46:40 solution and to comply with adb2 and secondly it would reveal the process that an architect would routinely go through and i felt that in the end actually looking back at it i think it's the
00:46:51 looking back at it i think it's the process
00:46:52 process that has been more revealing and interesting than the product because i i mapped out i reported carefully
00:47:00 carefully on the process that i actually adopted to solve this to solve this problem and i i hope that that gives useful insight because against that ins in section four
00:47:11 because against that ins in section four my report
00:47:12 my report i've criticized what was done but i've also been able to criticize the way in which things were done yes thank you
00:47:20 thank you can you explain the role that a review of the building regulations and the associated guidance had in the preparation of your indicative approach
00:47:29 approach yes i i place great importance on
00:47:35 this kind of work i think at the outset of a project uh it's very important to do i think i called it a code review
00:47:45 and it would be wrong with me to say that at the outset of every project an architect must sit down and do a code review if an architect's been doing a particular kind of building repeatedly or parts of a building
00:47:57 repeatedly or parts of a building repeatedly some architects are doing high-rise new builds all the time they wouldn't do a code review because they know the codes they would of course want to keep up to date with any changes if you haven't worked
00:48:10 with any changes if you haven't worked on that
00:48:10 on that type of building before a restaurant whatever it is then i think a code review is absolutely essential and i carried out that myself at the beginning
00:48:20 beginning very thoroughly actually in order to understand what i would have to be achieving with the design with the details design as i went through it now you refer in your report to the development of a cavity barrier
00:48:32 to the development of a cavity barrier strategy
00:48:33 strategy yes can you use the word cavity barrier yes yes what is a cavity barrier strategy in particular well first of all it's i developed that term entirely for this situation
00:48:44 term entirely for this situation but there are choices from the beginning as to
00:48:48 as to where you put i mentioned this again yesterday where you put the cavity bars particularly the vertical ones several choices and so decisions have to be made and the only way i can think of sensibly
00:49:01 the only way i can think of sensibly doing
00:49:01 doing that is to holistically get the entirety of the building in the mind look at all of the different circumst
00:49:12 look at all of the different circumst all the different situations that have to be dealt with and then piece together an approach and there may be some um some adjusting some rationalizing the piece together
00:49:24 some rationalizing the piece together and approach which is as clear and simple as possible that will deal with every eventuality that is found in the building
00:49:30 building out of that we end up with a thing that's called and i remember this right from the beginning of my career you end up with a thing called typical details and specials the typical details will deal with
00:49:41 the typical details will deal with usually 90 of the building and then you've got the specials whatever it might be their circumstances which have to be dealt with uh
00:49:49 with uh in an entirely different way they've got to be addressed carefully an argument must be careful to sort out the typical and then to identify the specials and get them sorted as well all of that went into the cavity barrier
00:50:00 all of that went into the cavity barrier strategy but the big thing i'm sorry if the answer is too long but the key thing i i'd like to uh emphasize is that i don't think that an architect can look can apply adb2
00:50:12 an architect can look can apply adb2 to individual details of the building the
00:50:16 the building the facades must be looked at as a whole do you take the view that a reasonably competent architect ought to have developed a cavity barrier strategy for this project
00:50:27 strategy for this project yes either have one or develop one and just very very briefly why is that because uh
00:50:38 because uh if you don't do that you're at great risk of
00:50:41 risk of failing to apply adb2 can we then look at your
00:50:44 at your report please uh at um phyr5029 and look at page 16 please
00:50:55 and look at page 16 please i'd like to go to paragraph 4.1.40 where you say i note that whilst cavity barriers have been extensively used in connection with various lightweight
00:51:06 connection with various lightweight clouding systems of metal and or composite construction dr lane has
00:51:10 has at paragraph 10.3.39 stroke figure 10.19 of her report advised that the effectiveness of cavity barriers can be compromised in circumstances where the rain screen panel distorts due to heat
00:51:22 panel distorts due to heat that is a manner that i will leave matter that i will leave to other experts to comment on i was not aware of such potential problems before reading dr lane's report and would not think it appropriate to criticize studio e or any other architects who were also so
00:51:34 architects who were also so unaware on that subject is it correct that this issue here is that if the cladding panels deform in heat and then fall away then the external cavity essentially ceases to exist or at least
00:51:48 essentially ceases to exist or at least the spread of smoke and fire is not hidden from view and therefore the role of the cavity barrier becomes non-existent that's redundant right right and is it your opinion that the use of open state cavity barriers
00:51:59 cavity barriers which are mechanically fixed and bonded as you propose in details three to six of your report and we can get to these if we need to as opposed to the system designed or approved by studio e
00:52:10 approved by studio e would resist fire spread for a reasonable period the arrangements that i have shown would inhibit the passage of fire [Music]
00:52:22 [Music] this is particularly important around the windows so the answer is yes the answer is yes so you don't think and this is in contra distinction
00:52:34 distinction that it would be defeated by the issue dr lane has identified namely that metal cladding melts or deforms and renders the intumescent cavity barriers ineffective i'm sorry i i know
00:52:47 ineffective i'm sorry i i know um i have greater insight into that question
00:52:51 question i cannot know the answer to that much work will be done on that more work than has already been done i'm sure people like dr lane will give very good
00:53:02 people like dr lane will give very good advice in the future on that all i can say is that in applying the adb to um as it stood at the time in pursuit of
00:53:14 stood at the time in pursuit of satisfying the building regulations the arrangements that i have shown in terms of the positions of the cavity barriers
00:53:21 barriers uh i believe complies with that and any other arrangement arrangements i've seen drawn by studio and harley do not comply
00:53:33 by studio and harley do not comply do you consider that your arrangements would keep the cavity barriers functional for sufficiently long to resist flame spread adequately um
00:53:44 to resist flame spread adequately um that is a question i i simply cannot answer because uh the ferocity of the fire due to the the fuel available to it fires burn at
00:53:55 fuel available to it fires burn at different temperatures i mean we can think of 911 where plane 30 tons of fuel high octane fuel launched into the building
00:54:05 building that that gives an instantaneous fire of the most
00:54:08 the most tremendous heat that is a different fire to the kind of fire you might get in the living room where pieces of furniture ignite and take a relatively long time to achieve
00:54:21 a relatively long time to achieve their full heat and probably don't achieve a heat anything like the first one i described the 911 i was involved a little bit in comedy and that's why i know
00:54:32 that's why i know so it's the intent and i did work on the fire research test station as you know it's see it's the intensity of the heat and the speed with which that um
00:54:44 and the speed with which that um that fire accelerates which is the problem
00:54:47 problem i have no way of knowing how long the cavity barriers would have blasted in those circumstances what i can say is that they would have done a better
00:54:58 is that they would have done a better job
00:54:58 job than what was shown because what was shown didn't exist in some respects but the key part is i believe that the the the perimeter of the windows and particularly the jams
00:55:10 particularly the jams and i don't want to tread on the toes of the specialist fire um experts but it's evident to me that the head and the sill had a level of protection because of the
00:55:23 had a level of protection because of the aluminium
00:55:24 aluminium shelf angles now those don't satisfy adb2 but nevertheless i've seen them on the building and they remain in many cases reasonably intact
00:55:35 intact the the weakness was the jams as the model shows very clearly there we have the 120 millimeter vertical gap something like a meters height yeah and
00:55:46 something like a meters height yeah and we're going to come to we're going to come up okay i'm sorry but thank you for that now can i ask you to go to phyr 5029 at page 73 same document page 73 and let's look
00:55:59 same document page 73 and let's look together at paragraph 4.3.80 there towards the foot of the page underneath figure 4.56 and the context of this is uh the emails in early november 2013 between
00:56:12 in early november 2013 between x over and studio e about cavity barriers and you say here
00:56:24 in paragraph 4.3.80 from the fifth line down
00:56:27 down you say however whilst i'm aware that dr lane has expressed concern in this respect
00:56:32 respect such concern was not widely spent publicized at the time of preparing the tender documents for the 2012 to 16 works
00:56:38 works cavity barriers were widely used in such circumstances and i would not wish to criticize studio e in this respect the exhibit below from sidereel's current website clearly implies
00:56:48 implies that the products are suitable for use within rain screen cladding systems and there is no qualification to the effect that the products are not suitable for use with metal rain screen systems um do you
00:57:00 systems um do you accept however that it's not appropriate for a designer to accept the suitability of a product based either on the fact that it's commonly used or on assertions
00:57:11 commonly used or on assertions made by product manufacturers without at least a degree of interrogation by the designer
00:57:18 yeah i i think that follows yes now let's just explore this a little bit further then a paragraph 4.4 point um one two three of your report and this is
00:57:29 one two three of your report and this is a page one two seven of the same document let's just go to that four point four point one two three um you say there and this is in the context of the end of the
00:57:41 this is in the context of the end of the email run in march 2015 involving terry ashton
00:57:46 ashton neil crawford uh and uh ryden um you uh say that on the 31st of march 2015
00:57:56 2015 mr crawford emails the following comment to mr ashton and you give the reference thanks this was my point as well metal cladding always burns and falls off hence fire stopping is usually just at the back of the cladding line
00:58:07 the back of the cladding line thanks for this confirmation anyway again this shows a lack of understanding of the principles of cavity barrier installations and a repeated misuse of the terminology through reference to firestopping you see that
00:58:18 see that yes now before i come to a question on that mr crawford uh whose email that was as you say clarified that email in his evidence to
00:58:29 clarified that email in his evidence to the inquiry can we go to the transcript please for day 10 and go within that to page 153
00:58:39 but at line 14
00:58:44 uh i ask him having shown him the email i say now i just want to focus on the words metal cladding always burns and
00:58:56 words metal cladding always burns and falls off were you saying that there was no point in installing cavity barriers behind the acm rain screen because in the event of an external fire there would be nothing to hold them in place
00:59:07 place to seal the cavity answer fire stopping you mean question a question well and then he says that's specifically what that's referring to holding fire stopping in place if if it
00:59:19 holding fire stopping in place if if it fell off a cavity barrier would be kept in place and then he goes on
00:59:24 on on page one five four if we can just flip to that um sorry to interrupt you but i don't understand what's being said there but we'll never come back to it well we will
00:59:35 come back to it well we will um let's just show you the whole of his evidence and we can certainly come back to it
00:59:38 to it and we'll do but just let me show you page 154
00:59:42 page 154 um he he uh he goes on to say uh at line six it's a poor choice of words
00:59:50 words it should have been melts and fails and falls off but that was my experience and the reference specifically was the previous projects where i had been working within the best way to explain it is within a building you have compartments and you
01:00:02 building you have compartments and you have the facade which can be anything from curtain walling or brick whatever it is but the compartment which you know in this case would be an apartment
01:00:09 apartment you have compartment walls that are lines of fire resistance and the external wall it generally isn't a line of fire resistance unless you have a boundary issue and then he says so what happens in if
01:00:20 and then he says so what happens in if you have a developed fire scenario then the compartment itself is protected but the facade will fail buckle melt fall off and the specific reference i made in my witness statement was where i had been working on a project and it was made clear to me
01:00:31 project and it was made clear to me that that's what happens i think it's sometimes it's misconstrued people think there is a requirement for some level of fire resistance on the external wall and there isn't
01:00:42 on the external wall and there isn't basically in a fire scenario they fail except where you have the relative boundary issue now that was his evidence now just read that last sentence again basic basically in a fire scenario they
01:00:55 basic basically in a fire scenario they fail except where you have the relative boundary issue now um i've shown you
01:01:04 a large amount of what he told the inquiry
01:01:07 inquiry what is your opinion on the distinction that's being drawn here and in the emails between fire stopping
01:01:14 stopping and cavity barriers well fire stopping is defined in adb2 um that's the first thing uh you can look it up in the index you
01:01:26 uh you can look it up in the index you can find it in the definitions i can't remember where but i've read it it's defined um it's also on diagram 33 i believe that's the correct diagram cavity barriers are also defined um
01:01:40 cavity barriers are also defined um they're in the index they're in the definitions and they're in the diagram 33 and they clearly have a different function the fire stopping is to
01:01:53 stopping is to basically fill imperfections in connection so that if you've got a concrete floor for example coming up against a brick or block wall there may be a gap between the two
01:02:04 between the two that is inside the building that will be sealed with fire stopping cavity barriers have a different function and they are as their name suggests
01:02:16 and they are as their name suggests for placing inside the cavities and the principle
01:02:20 principle there is is to inhibit the passage of fire
01:02:23 fire into the cavity it's also out of the cavity
01:02:27 cavity around openings windows doors at the top and at the bottom and then at various intervals through in order to inhibit uh or impede the
01:02:39 in order to inhibit uh or impede the passage of fire if fire gets into the cavity to impede its onward passage so they're quite different things and they should not be muddled up when it comes to an external cavity wall
01:02:50 when it comes to an external cavity wall and particularly the cavity within the rain screen system is there a distinction between fast stopping and cavity barriers
01:03:00 when it comes to an external wall um
01:03:05 well i described the relationship between the external wall and the internal structure yes i haven't seen uh i don't remember
01:03:18 yes i haven't seen uh i don't remember on diagram 33 seeing any fire stopping actually within the external wall itself all the all is shown there is cavity barriers
01:03:32 do you agree that there's no material distinction between the effectiveness of a cavity barrier and the effectiveness of fire stopping if the metal cladding were to fail and fall off
01:03:42 fall off exposing the external cavity
01:03:48 sorry could you ask that again yes is there a let me try it differently is there a material difference between the effectiveness effectiveness of a cavity barrier on the one hand
01:03:58 one hand and fire stopping on the other if in in in any case the metal cladding were to fail and fall off in the event of a fire exposing well there would be a passage around evil so um
01:04:10 evil so um the outside is if there's no if there's no cavity left because one part one leaf of the cavity is gone whatever it's made of um then whether it's fire stopping or a
01:04:22 then whether it's fire stopping or a cavity barrier that will be there'll be a route around it if acm
01:04:27 it if acm such as the rainer bond pe 55 was going to fail and fall away in a fire and i take your point about it may depend upon the magnitude of the fire but but generally speaking if it
01:04:38 fire but but generally speaking if it was going to fail and fall away do you consider that an alternative approach to the cavity barrier strategy should have been adopted
01:04:50 we well the the with respect um the missing word there is
01:04:58 is is time it's the length of time um everything in the end is going to burn fall away you know the whole building will collapse in the end the fire is maintained and grows to such
01:05:10 the fire is maintained and grows to such intense
01:05:10 intense levels of magnitude as the term you used the issue here is to provide protection for the periods that the adb ii
01:05:22 for the periods that the adb ii guidance gives that's what the uh um the requirement of the design team that was the requirement that the design team had to comply with um so yes the cladding um
01:05:34 um so yes the cladding um will eventually burn and fall off yes um any any cavity barriers that are left at that time will be breached of course but adb2 is giving guidance to
01:05:46 but adb2 is giving guidance to inhibit the passage of fire for a period of time and that's for the fire brigade to get et cetera et cetera you know that story and so i i think in a sense i'm not moved by the fact that the
01:05:58 i'm not moved by the fact that the cladding will fall off brick walls collapse under intense fire coming back to your indicative approach can you just tell us in as briefly as
01:06:10 can you just tell us in as briefly as you can
01:06:11 you can what it is about your indicative approach so far as concerns the cavity barriers
01:06:17 barriers which would give the fire brigade more time
01:06:20 time than they had with the actual cavity barriers actually installed on the building
01:06:25 building well if i may there's there's two parts of that question and i'll just be very quick the first is the difference with the indicative design that i've shown is that it complies i believe with adb2
01:06:36 that it complies i believe with adb2 full stop
01:06:37 full stop so if there's a fault with adb2 then that's another issue but it complies with that
01:06:44 with that it will take specialists to advise how long against various degrees of magnitude of fire that situation that i've shown may have delayed the fire
01:06:55 delayed the fire but i am absolutely and i i can't qualify my answer with that level of information i haven't done i wouldn't be capable of doing the investigations but i do know as sure as night follows day
01:07:07 night follows day that if you've got a 120 millimeter gap that is a meter tall and you've got fuel both sides of that gap then the fire is going to move through that gap if you have
01:07:19 that gap if you have a material which has been designed to delay the progress of fire and it is packed in there tightly which is what it should have been then the fire is going to be delayed
01:07:30 fire is going to be delayed and therefore the fire brigade will have longer
01:07:33 longer to deal with the situation and would it follow therefore that the later it would be that the cladding would eventually fail and fall off exactly i see and it may be that the fire would have been put out and again
01:07:44 fire would have been put out and again that speculation so others will qualify what i say but it may be that the fire would have been delayed sufficiently for the fire brigade to put it out before it got into the cladding that's something that others will give
01:07:56 that's something that others will give better advice than me on can we then go to phyr
01:08:00 to phyr 5029 at page one two six so we're in your report page one two six and let's look together at paragraph four point four point one two one
01:08:12 four point four point one two one uh and uh you uh are considering here mr ashton's uh email to mr crawford or reply to mr crawford on the 31st of march
01:08:24 crawford on the 31st of march 2015 and you've given the reference to that exa50715 and that's the email from terry ashton to neil crawford of that date where mr ashton says
01:08:38 of that date where mr ashton says uh in the third line but let's take it from the top in fact it's probably better
01:08:42 better this isn't something that would necessarily form part of the fire safety strategy for a building therefore it would not have been dealt with in the fire safety strategy for this building i agree with ben kay i think he means
01:08:53 i agree with ben kay i think he means ricky k
01:08:54 ricky k of siderise there rather than ben bailey of
01:08:57 of harley just to make the point i believe that a cavity barrier is all that is required in this application even if we were to agree with rbkc it is difficult to see how a firestop would stay in place in
01:09:08 how a firestop would stay in place in the event of a fire where external flaming occurred as this would cause the zinc cladding to fail
01:09:16 and then you go on to say um that uh um this response brings the earlier x over statements into question and you say this as i cannot understand
01:09:28 and you say this as i cannot understand how the statement below can be reconciled with mr ashton's comment above it seems to me that a statement confirming that the proposed changes will have no adverse effect on the building in relation to external fire spread
01:09:40 relation to external fire spread could not be made without having given due consideration to the external walls construction and then you set out an extract from the xavier fire strategy report and just to be clear this is issue 3 of the 7th
01:09:52 to be clear this is issue 3 of the 7th of november 2013 at paragraph 3.1.4 compliance with b4 external fast bread it is considered that the proposed changes will have no adverse effect on the building in relation to external fire spread
01:10:03 fire spread but this will be confirmed by an analysis in the future issue of the of this report
01:10:10 now my question is um ought mr ashton's comment have motivated studio e to provide more details as to the cavity barrier strategy
01:10:29 yes i i think that's correct and or mr ashton's comment uh have motivated or prompted studio e to confirm to the tmo and ryden
01:10:39 and ryden that there is an uh concern in respect of cavity barriers staying in place and thus fire safety strategy as developed thus far was incomplete
01:10:50 far was incomplete and needed further work so when i answered the previous question
01:11:01 so when i answered the previous question i was
01:11:02 i was answering it on the basis that studio he should have ensured that mr ashton had all the information that he needed
01:11:11 needed to answer the the question because i think that there was a lack of clarity on mr russian's part as to how the external wars was um uh to be fabricated
01:11:22 was um uh to be fabricated yes and should that have prompted that lack of clarity have prompted studio e
01:11:29 studio e to go to the tmo uh its original client uh and potentially its erstwhile client as well and ryden uh its client um to tell them that there was a
01:11:39 was a concern about the cavity barrier strategy
01:11:43 strategy ryden yes i personally i i prefer not to bother clients too often during a project but i think that um this was certainly a time for everybody
01:11:55 this was certainly a time for everybody to get their heads around the issue very good and as an architect would you reasonably expect the fire engineer
01:12:02 engineer to limit their advice to cavity barrier
01:12:06 placement i um
01:12:12 i um i think that they they have to be sure that they understand the entirety of the construction there may be having established that
01:12:23 there may be having established that and given general advice there may be occasions when a specific question is asked and they might restrict their advice just to that that part but they need to be sure they
01:12:34 that part but they need to be sure they understand the whole before they begin advising
01:12:37 advising and in the context of this particular email and and the emails that surround it would you have ex
01:12:45 have ex would the reasonably competent architect have expected the fire engineer in this case xover simply to have limited their advice to cavity barrier placement
01:12:56 cavity barrier placement or to have come back to them and said well i now need lots of information so that i can now produce my uh promised future issue and do the analysis of external fire spread on all the information
01:13:08 spread on all the information the the the architect should have ensured that the the uh that the work was completed by xover
01:13:16 xover alternatively that somebody else did it could we then turn to uh page 127 of this
01:13:23 this report next page and look at uh paragraph 4.4.124 where we see mr pearson of xover's email to ashton mr ashton of the 31st of
01:13:35 email to ashton mr ashton of the 31st of march
01:13:36 march 2015 and you quote from that uh extensively i better read it all to you before coming to what you say about it he says we note that the barrier against fire spread between floors is provided through the
01:13:47 floors is provided through the connection of the structural floors to the existing external walls the existing external walls are expected to provide sufficient fire resistance to prevent fire from entering the cavities at or near floor or ceiling
01:13:58 the cavities at or near floor or ceiling level
01:13:59 level we would not rule out that fire could enter the cavity if there is flaming through the windows however if significant flames are ejected from the windows this would lead to failure of the cladding system with the external surface falling away
01:14:10 with the external surface falling away and exposing the cavity eliminating the potential for unseen fire spread the standard cavity barrier should be sufficient to prevent fire spread between floors while there remains a cavity in view of
01:14:21 while there remains a cavity in view of the above we do not feel that there should be a need for a two hour rated fire break in the cavities along the lines of the compartment floors or walls and then you say commenting on that email again this demonstrates to me a
01:14:33 again this demonstrates to me a fundamental lack of understanding of the principles involved in adb-2 guidance with respect to inhibiting the passage of fire into the cavity behind the rain screen cladding and thereafter onwards through it
01:14:44 through it can you summarize for us the what you say is the fundamental lack of understanding here
01:14:55 the i i think um this inquiry has put a spotlight on the issue of compartmentation when it comes to external walls
01:15:07 comes to external walls we have a compartment think of it almost like just a rectangular box there's a compartment it's got an internal wall which opens onto the
01:15:18 internal wall which opens onto the public areas of the building the stairs the lifts etc it's got two sidewalls which link to the next flat usually and it's got a a a floor and a ceiling so there you have a compartment the
01:15:30 so there you have a compartment the final face of that compartment is the outside wall and if that wall as i was mentioning a few minutes ago is sealed to the floor the car
01:15:41 is sealed to the floor the car compartment the internal compartment floors and the walls
01:15:45 walls then you have a sealed box what was done here was was to produce an entirely new condition which is uh a cavity outside the building there wasn't
01:15:57 cavity outside the building there wasn't one before and so we now have the potential for the passage of fire within that cavity itself i think [Music]
01:16:08 [Music] ms menses suggested in her evidence that the compartment flaws should have been carried straight through the external wall to
01:16:19 straight through the external wall to its perimeter uh that would be to the back of the vein to the back of the acm i don't think that that is the way that um
01:16:31 um architects would interpret a db2 guidance
01:16:35 guidance the guidance doesn't suggest that the cavity
01:16:38 cavity that the compartment wall has to be carried right to the back face of the outer lining it suggests that cavity barriers should be placed in there and i think that um this um
01:16:49 and i think that um this um um response from x over mr pearson should have summarized the situation as i've just summarized it and indicated that adb2 requires uh
01:17:01 and indicated that adb2 requires uh the arrangement that i've shown on the indicative scheme i see now there may well be shortfalls with adb2
01:17:09 with adb2 in fact i think they certainly are but that's that's what is suggested i see um
01:17:17 i see um and if i may an expert organization like xover might have pointed
01:17:23 pointed to the weaknesses and the problems and suggested
01:17:26 suggested an alternative route or greater care but i wouldn't expect an architect to do that
01:17:36 i'm sorry you didn't ask that question i just wanted to be a bit more precise about if you can summarize in a sentence for me
01:17:42 for me what it is that mr pearson has got fundamentally wrong
01:17:50 oh yeah it's fine
01:17:54 perhaps you want to look at the second paragraph down in particular of the quotation yeah i'm looking at that
01:18:21 well however if significant flames were ejected from the windows this would lead to failure of the cladding system with the external surface falling away and exposing the cavity
01:18:33 the the key point here i think is where those flames are going to go are they going to go on the outside of the acm or are they going to go
01:18:45 of the acm or are they going to go to the inside of the acm if they go to the inside of the acm there is a potential for a far greater um ferocity of fire it's uh
01:18:56 um ferocity of fire it's uh it's it's there are conditions there the chimney effect for the start um there are conditions it's almost like a bellows far greater heat
01:19:06 heat can be uh and there's fuel inside that cavity
01:19:09 cavity if that fuel that is the um celitex catches fire and it's burning rapidly in that
01:19:16 that tight area with a plentiful supply of oxygen
01:19:20 oxygen through it it's like a chimney but that the impact of that on the back of the um acm um will be considerable we talked yesterday
01:19:31 will be considerable we talked yesterday about the cuts to the edges of the um of the trays we've got the polyethylene which can pour out inside so i i think that um that
01:19:42 so i i think that um that those are all issues that should have been in um mr pearson's mind i think is it come on summarize it this way
01:19:49 way perhaps that and i know we're interpreting a document and it's not really your role certainly not my role to do that but is your understanding from the point of view of an expert architect that the basic error here
01:20:02 architect that the basic error here is that he has confused a flat on fire with a cladding system on fire
01:20:11 i i think that is that is correct um but i'm you see we go back and look at words you've written a fundamental lack of
01:20:22 you've written a fundamental lack of understanding of the principles involved in adb2
01:20:26 in adb2 i if i may just like to go back significant flames rejected from the windows
01:20:30 windows significant flames can be ejected from the windows without much adverse effect because
01:20:34 because as we know from um i think it was mr torreira's advice and i know this from moving my hand towards a candle on the dining table you can move your finger towards the candle there's no burning sensation not
01:20:46 candle there's no burning sensation not at all
01:20:47 at all you can travel right to within half an inch of the candle and then suddenly the the in the the exponential increase in temperature is extraordinary the reverse is also true as mr torreira told us
01:20:59 true as mr torreira told us so flames can come out of the building into the open air and those flames don't do that much damage it's when they get
01:21:06 get into a situation like the cavity with fuel there is the danger yes thank you um mr chairman is that a convenient moment for a break i think it probably is yes um thank you
01:21:18 i think it probably is yes um thank you we'll have a short break now thank you mr usual rules no talking while you're out of the room please at least about your evidence that is and we'll come back at 20 to 12 please thank you very much
01:21:46 all right 20 to 12 please
01:40:44 would you like to ask us to hire to come back in please
01:41:02 uh all right mr tired ready to carry on yes i
01:41:07 i am um sir but could i ask mr miller to please would you take me back to mr pearson's um um quote because i i'm not happy that
01:41:18 um um quote because i i'm not happy that i
01:41:19 i gave a concise and clear answer on that yes of course could we go to phyr 5029 at page 127
01:41:30 right i was concentrating i think too much may i speak yeah i was concentrating too much on the second paragraph and if i take that from the top
01:41:37 the top down we note that the barrier against fire spread between flaws is provided through the connection of the structural flaws to the existing external walls the existing external walls are expected
01:41:49 the existing external walls are expected to provide sufficient fire resistance to prevent fire from entering the cavities at
01:41:52 at or near floor or ceiling level well that i don't think is adequate and it's not strictly true the jams have to be considered equally
01:42:05 the jams have to be considered equally the next sentence says if significant flames are ejected from the windows now i assume that to mean
01:42:13 mean through the windows whether the glass is broken or not but not around the windows the key here is that the fire
01:42:19 fire past we know through and around the windows this is absolutely critical in view of the above we do not feel that there should be a need for trash
01:42:31 there should be a need for trash rated fabric well that's a fair answer to the question about the cavity barrier but to to say that we note that the barrier against fire spread between those is provided for the connection the structural flaws
01:42:43 for the connection the structural flaws to the existing external walls that is not adequate because if you get that right that is that it that implies that that will stop
01:42:51 will stop fire spreading but they won't if the fire goes out through the jams then it's in the cavity and it can spread
01:42:59 spread between the floors i think i was unwise in the use of the word a fundamental lack of understanding i am sure mr pearson fully understands but i think that this
01:43:11 understands but i think that this demonstrated uh a failure in the advice because he should have called for and x over should have called for the complete information on the cavity barriers in order for them to give the
01:43:23 barriers in order for them to give the proper advice thank you thank you thank you very much now before i continue uh on to the next topic uh which will be cavity barriers at the
01:43:34 which will be cavity barriers at the head of the window i feel i need to correct something that you said earlier and i perhaps encouraged you in and this was about the timing of the publication of the cellotex rs 5000 compliance guide
01:43:47 of the cellotex rs 5000 compliance guide can we go back to that document because i drew your attention to the fact that it was dated as a february 2015.
01:43:57 2015. um and you said uh that when considering the compliance guide the timing of course of all this is very late you said because the document was not i
01:44:08 said because the document was not i think available at the time that this product was first proposed so this would an architecture has adopted this product earlier on would not necessarily be revisiting the hood of this conversation and the point that you'd made just
01:44:20 and the point that you'd made just before raising that issue was that on page three of the compliance guide uh it was absolutely clear that when you looked at the right-hand side of the page page three that the classification applies only to the system as tested and detailed
01:44:32 the system as tested and detailed in the classification report and that report covers the end use application that's the text of it now the point i want just to put to you is that in fact this compliance guide
01:44:44 is that in fact this compliance guide was available in august 2014 not only as at february 2015 and can we just look at one or two documents just to make that good first please cel6012
01:45:06 now that is the range screen cladding compliance guide and if we look at the next document cel four zeros one two three seven
01:45:22 uh here is an email from jonathan room to ben sharman of harley of the 6th of august 2014 and 14.
01:45:34 august 2014 and 14. and he says in the second paragraph i have pleasure of informing you as of yesterday we've now launched the first pir board to successfully meet the performance criteria and br 135 for insulated rain screen clouding systems
01:45:47 screen clouding systems therefore acceptable for use in buildings above 18 meters in height and says he wants to come and launch the product and there's an attachment rain screen insulation launch
01:45:58 rain screen insulation launch and that was also provided to harley on the 27th of august 2014. um and that's cel706 let's just have a look at that cel706 please
01:46:10 cel706 please this is an email of that date 27th of august 2014 from jonathan room to daniel lancaster jones at harley and he's sending him the rs 5000 data
01:46:21 and he's sending him the rs 5000 data if it's correct that the compliance guide that i've just shown you was the document that was provided on those dates and that therefore harley was provided with the compliance guide in august 2014 would that change your
01:46:33 in august 2014 would that change your view
01:46:39 um
01:46:42 my view in which respect sorry well you you you said um the timing of this was very late and an architect who's adopted this product earlier wouldn't necessarily be revisiting
01:46:53 revisiting the whole of this conversation so if it's correct that all three documents were available in august to the architect instead of just the the two that the um i showed you earlier
01:47:06 the two that the um i showed you earlier but also the compliance guide as opposed to february 2015 would that change your view i i the uh can you give me the date
01:47:17 i i the uh can you give me the date um of the um employers requirements uh they were um issued to tenderers in november 2013. well i think that's
01:47:29 in november 2013. well i think that's the point the the specifier the architect in this case will carry out work necessary to get documentation completed and i don't think revisits
01:47:41 completed and i don't think revisits unless there's some major alarm or alert so i wouldn't expect them to have revisited it particularly can we then uh go to the topic i wanted
01:47:53 can we then uh go to the topic i wanted to come to which is the cavity barriers around the head of the windows please and before we look at the detail i just want to ask about the requirement for cavity barriers around openings um
01:48:05 for cavity barriers around openings um can we go first please to mr sones's oral evidence to the inquiry at day 21 of the transcript please
01:48:14 i'd like to go to page 73 at line 7.
01:48:20 and here ms grange is asking mr sones what was it about these provisions of adb that we've just looked at that would suggest to you that in a rain screen cladding system you wouldn't have to provide cavity
01:48:32 you wouldn't have to provide cavity barriers around openings and his answer was well this is line 11 well the approved document is silent on rain screen it doesn't discuss it but i believe the diagram 33 refers to a very conventional
01:48:44 diagram 33 refers to a very conventional form of construction and not a rain screen which is essentially outside the cavity is outside it's vented pressure equalized if you like it doesn't offer any resistance to flame
01:48:55 it doesn't offer any resistance to flame from the outside or flames coming around the window opening and then he goes on to say in line 19 so i couldn't have i would have read that as
01:49:06 have read that as unclear what is your opinion as to mr sones's reading of diagram 33 and adb in this respect diagram 33 is not a good diagram it
01:49:17 diagram 33 is not a good diagram it looks like a house um so that's the starting point but i think the intention is pretty clear that the colors are not clear you've got the very light gray for the cavity barrier i'm going entirely
01:49:29 the cavity barrier i'm going entirely from memory now and um you've got a diagram which is wrongly titled as well um which doesn't help but i think that between
01:49:39 between the uh the the language used words used in adb2 and the diagram it is absolutely clear that the uh surround
01:49:50 surround of of openings should have cavity barriers to inhibit the passage of fire now mr sainz and i'm summarizing his
01:50:01 now mr sainz and i'm summarizing his evidence i hope fairly said that he essentially left the matter to mr wreck of studio e whom he thought had consulted with perhaps xover siderise and harley on
01:50:12 perhaps xover siderise and harley on this
01:50:13 this if that's correct do you consider that mr sones's course of action was one which a reasonably competent architect heading up the design team at studio e
01:50:22 studio e would have adopted to leave this matter to mr wreck and others outside studio aoe for example x over or side arrives or harley
01:50:35 an architect carries an enormous amount of information in their head at the start of a job somebody needs to have their arms around if you accept that term the project and
01:50:48 if you accept that term the project and understand it it may be part of a very large project that are handed out to another person to look after for example the cladding that could be
01:51:00 for example the cladding that could be done
01:51:01 done but somebody at studio e needed to be able to report with great confidence that this issue had been dealt with and dealt with properly and i think that actually i don't understand
01:51:14 think that actually i don't understand enough about the way the firm was structured but i would not be happy mr wreck i think was was he a qualified architect or not
01:51:22 or not i think he came from have been in the country recently i think i'm not sure yes i would want to as an architect who's acted as a partner
01:51:35 as an architect who's acted as a partner and a project architect at various stages of my life i would want to be very sure that the person who was looking after this issue was um experienced enough um and i would want to be satisfied from
01:51:49 um and i would want to be satisfied from discussion with that person that they've got it right could we then look at your report at phyr5028 please at page 62.
01:52:00 phyr5028 please at page 62. and go to paragraph 3.8.12 on that page and let's look at the third line down i'll read the whole of it to you because it's only
01:52:09 it's only really short the window head straight concrete floor slab edge relationship is orthogonal and therefore the detail is easier as the following diagram shows however and for the same reasons it is
01:52:21 and for the same reasons it is imperative that the cavity barrier is located at the very extreme edge of the cavity so as to inhibit the entry of fire into the cavity superimposed on the diagram is a dotted red line which shows
01:52:32 diagram is a dotted red line which shows where the cavity barrier should be placed
01:52:34 placed in order to comply with the guidance given under adb 2 section 9. again i have also shown a continuous red line which indicates the position that was shown on the harley drawings and installed
01:52:45 and installed now the diagram that you've set up below that text i've just read to you is figure 3.30 you see that and we can see the
01:52:52 see the proposed cavity barrier position at the head of the window in the dotted red line with the dotted red um could we feed the diagram up a little please yes
01:53:04 yes so the dotted yes we can probably shrink it a little bit so we can see more of the diagram can we do that that's enough um the dotted red uh rectangle there is where you i think
01:53:16 rectangle there is where you i think would put the cavity barrier at the head of the window is that right yes as close to the window opening as possible yes and the hard solid
01:53:27 yes and the hard solid red line is as per the harley drawings that is correct now if we look at figure 4.49 of your report um on page um that well it's a phyr-50
01:53:39 um on page um that well it's a phyr-50 is 29.
01:53:41 is 29. we're in 28 at the moment which is flip over to 29 and go to page 66.
01:53:51 we can see here that you have uh extracted studio e's drawing 1279.09 one double zero double zero showing it that a cavity barrier
01:54:02 that a cavity barrier has been indicated that the window head level do you see yes so that's um where you you show that um and then if we go to your
01:54:13 um and then if we go to your supplemental report and i'm sorry to dot around
01:54:16 around i need all three together um if you go to phys
01:54:20 to phys 505 please i'm sorry six zeros five which is your supplemental report uh at page 55 and go to paragraph 6.4.5
01:54:34 you say there in contrast studios drawings as illustrated in figure 4.49 which we've just looked at showed a cavity barrier arrangement that closed
01:54:45 cavity barrier arrangement that closed the cavities at the very edge of the openings formed at the head of the windows and were thus compliant with the guidance of adb2 in this respect all their cavity barriers were not shown around not shown at the
01:54:56 were not shown around not shown at the ceiling jam positions of the windows can you explain having shown you all of those extracts can you explain what the purpose of the cavity barrier at the window head was yes could we go
01:55:07 at the window head was yes could we go back to the previous the last of the drawings we the last of the drawings that's uh p h y r uh five zeros 29 at page 66 i think is that the one
01:55:19 29 at page 66 i think is that the one you want
01:55:20 you want yes and could that be um made a little larger
01:55:24 larger yes perhaps focusing on the top yellow uh symbol the top cavity barrier there we go
01:55:35 we can see there that that cavity barrier
01:55:38 barrier is at the very bottom of the cavity over the window it's important to remember here that the cavity over the window spreads from
01:55:51 the cavity over the window spreads from column to column there are no intermediate parts where it's uh
01:55:56 it's uh the span block button spreads from column to column and the range shield goes from column to column so this condition here is showing the entirety
01:56:06 entirety of the gap between the two columns and the requirement is to inhibit the passage of fire into the cavity where there may be fuel certainly they
01:56:18 where there may be fuel certainly they don't want a fire in the cavity placing the cavity barrier as close to the top of the window as possible means that there is a an obstruction
01:56:29 means that there is a an obstruction to the free passage of fire at that point and there is no fuel within the cavity um to assist a fire
01:56:40 and why does the cavity barrier need to be at the very extreme edge of the window head at the extreme edge well as close to the window as it can
01:56:50 can be simply just so that there is no part of the cavity that is um that is easily accessed by a fire
01:57:02 that is easily accessed by a fire um so that all of the all of the cavity and any materials within the cavity are above the cavity barrier which is protecting them all um let's then look back at your figure
01:57:14 um let's then look back at your figure 330 at phyr before you leave that figure there's an interesting point on that as it's blown up right may i yes there is a yellow line that we're looking at
01:57:25 that we're looking at a yellow the cavity barrier showing yellow
01:57:28 yellow there is a dotted line running away from the cavity barrier to the right do you see that
01:57:33 see that yes that is the cavity barrier continuing around the column it then uh meets a vertical dotted line you can see five seven five is written through it
01:57:44 through it yes and there are two lines there they are the vertical cavity barrier coming down the column yes the dotted line of the horizontal cavity barrier does not continue around the column
01:57:55 does not continue around the column right it's absolutely key so there's your chimney again yes can we then look at figure 330 which is back at p hyr five zeros 28 please
01:58:07 hyr five zeros 28 please phyl50 is 28 at page 62 which is your um i think indicative position
01:58:13 position of the cavity barrier you you you we've looked at that a moment ago is the position in which you've shown the cavity barrier at the window head the only position which would meet with the meet the
01:58:25 which would meet with the meet the requirements of adb paragraph 9.3 or are there any other positions which would also comply
01:58:36 i i no i think it must be there as close to the edge of the cavity as possible
01:58:44 possible now we can see from this diagram that in the position shown at figure 330 here that part of the cavity barrier
01:58:51 barrier would not actually abut the concrete floor slab but but would a butt against the continuous aluminium angle in front of the void yes is that correct yes now mr lam gave some evidence about
01:59:04 yes now mr lam gave some evidence about the efficacy of that arrangement and i'd like to show you the transcript of what he said and then ask you some questions about that could we go please today 38 at page 104.
01:59:22 uh he says there at line nine but the window hangs down below the structure
01:59:30 structure so you wouldn't expect to put a cavity barrier where it can't be backed up by the concrete structure so for one you would have to put it at least at the bottom of that concrete floor slab the second thing is this is a refurbishment the concrete isn't crisp
01:59:42 refurbishment the concrete isn't crisp and flat and straight as it's shown on that drawing it's quite a deflection so the aluminium this special profile at the head of the window there would be gaps between that and the concrete so if it was mounted on that
01:59:53 concrete so if it was mounted on that aluminium profile fire could get behind the cavity barrier and you would also have to contend with the cavity barrier sealing over all the fixings
02:00:00 fixings so that appeared to be the cleanest safest position and if and if we go over the page to page 105 we can see that
02:00:11 to page 105 we can see that mr lam is then shown your figure 330 by ms grange and at line 21
02:00:23 mr lam says well as i say i think he's shown it too low he is you he's shown it too low and he's assuming that the substrate that the aluminium angle is bolted to is
02:00:35 that the aluminium angle is bolted to is flat which it clearly wouldn't be and then he goes on to say
02:00:41 uh in line 25 i don't think it should be hanging below the concrete because the fire protection the rating of the fire product relies on this on a suitable substrate behind it
02:00:53 it and then he goes on at page 106 at line 15 if we can just look at that to propose a solution and he says uh i think lifting it up
02:01:04 i think lifting it up very slightly would be better and then another solution would have to be added to that to protect between the aluminium bracket and the concrete also
02:01:15 and then i'm just going to show you some more passages at page 106 at line 25 he's asked so just to be clear
02:01:25 clear are you disagreeing with me that it would have been possible to do what mr hyatt is saying and he says it would be possible to do exactly what he's shown yes and then at page 145
02:01:38 yes and then at page 145 flipping on a number of pages in the transcript of that please line 19
02:01:45 uh he's uh he's asked there and degraded and degraded etc did you ever think about whether you could include something different there perhaps not mineral wool but a steel
02:01:56 perhaps not mineral wool but a steel angle
02:01:57 angle so do you agree with me that approved document b does envisage that other materials could prop could form proper cavity barriers including steel and he answers at line 25 yes it
02:02:08 and he answers at line 25 yes it certainly does however if the proposal uh that we made was acceptable there's no need for any of that and then the next page page 146 at line three or line let's say line
02:02:21 at line three or line let's say line nine two he's asked the question well for a forget for a moment what studio he did and whether they picked this up just in terms of your own work was it ever considered that there could be a different solution to a cavity barrier
02:02:32 different solution to a cavity barrier in this location if you were worried about putting something like a siderise cavity barrier in that location the shea button is to hire it
02:02:38 hire it was there any was there ever any consideration to for example putting a metal angle as per section 9 of adb and he says at line 10 you could have put a metal angle or a z
02:02:50 put a metal angle or a z section on the inside of the extruded aluminium angle you see that and he goes on at line 13 to say i guess that would be something that could be proposed question yes but no consideration was
02:03:01 question yes but no consideration was ever given to that not as far as i'm aware
02:03:04 aware no now but i've read you a lot of what he
02:03:07 he said and what was grange put to him about your diagram 330 and i just like to understand your opinion about his position as reflected in the evidence i've read to you
02:03:18 evidence i've read to you um can we go back to the figure 330 which is the subject of this discussion p h y r 5 0's 28 page 62.
02:03:30 and if you need any more of that than this we can look at it first do you consider that mr lam's uh location of the cavity barrier as shown in the harley drawing and figure 330
02:03:42 in the harley drawing and figure 330 as you've shown it was acceptable no do you agree that in order for the cavity barrier to be fully effective it's full width should about a solid surface
02:03:53 about a solid surface well excuse me i beg your pardon it says position of compartment floor horizontal cavity barrier um that cavity barrier
02:04:04 um that cavity barrier to to meet that requirement had to be within the depth of the compartment floor
02:04:09 floor uh it i believe uh it looks like it's within the depth there but we've found plenty of examples where it's not it's above the compartment floor
02:04:18 floor but that's the cavity barrier that's dealing with the compartment floor if they were to put the cavity barrier higher that's not immediately over the window opening but higher i'm sorry i'm using my hands to describe
02:04:30 i'm sorry i'm using my hands to describe this then
02:04:31 this then that still left a cavity under that cavity barrier that needed to be protected from the window opening so a second cavity barrier would have had to have been introduced lower down and then my question
02:04:45 lower down and then my question do you agree that in order for the cavity barrier or a cavity barrier it to be fully effective it's full width should a butt a solid surface it's full width top to bottom
02:04:56 width top to bottom should it depth we would use the word yes
02:04:59 yes if you don't mind no depth depth but it's called depth about a solid surface yeah i i don't know the answer to that um
02:05:06 um i qualified the indicative scheme as being one that would form the basis for robust discussions with specialists and that would be the cavity barrier manufacturer possibly certainly xover
02:05:18 manufacturer possibly certainly xover and with building control when the idea is mature we're mature there may well have been a suggestion that two cavity barriers one on top of the other should be used or a slightly different bracket arrangement
02:05:30 different bracket arrangement but the cavity barrier i think would be would perform well whether fire was attack attacking the back of it or the front of it or the bottom of it it's uh it's a consistent material all
02:05:42 it's uh it's a consistent material all the way through um but as i say i don't offer it as the absolute definitive solution it's a it's a considered proposal for discussion with
02:05:53 discussion with experts
02:05:56 if about half of the depth of the cavity barrier doesn't abut a solid substrate as you've shown in your indicative position with the dotted lines there but
02:06:07 position with the dotted lines there but hangs below it would you consider that that would or might risk a compromise of the effectiveness of the cavity barrier well there are two issues there the
02:06:18 well there are two issues there the first is the um the robustness of the fixing the cavity barrier has to be connected to something that is going to be reliable and the aluminium may fail although as i say the evidence
02:06:31 may fail although as i say the evidence is that
02:06:31 is that the aluminium shelf angles were pretty intact but um it's got to be a robust fixing so that would be a consideration
02:06:42 consideration and we're certainly getting very low on the concrete um to get the kind of the the the normal spikes which um sidewise
02:06:50 sidewise use they bolt those to the wall and then they um
02:06:53 they um impale the cavity barrier onto it so it's certainly getting uh low for that so that's an issue that would have to be discussed the second point that mr lam made was the um
02:07:04 the um the um
02:07:07 the um the the the lack of the fact that the edge of the concrete slab may have fissures and it may wave slightly i agree with that concern
02:07:21 wave slightly i agree with that concern but i would point out that as i showed on monday
02:07:24 on monday there is some substantial grooves in the concrete um columns that needed to be filled and i've showed a way in which that could have been done
02:07:35 a way in which that could have been done i don't think that any gap between the back of the cavity barrier shown here and any unevenness on the spandable panels would have been anything like the size of those grooves um if it did
02:07:46 the size of those grooves um if it did become a concern and this again is where the
02:07:48 the the kind of conversation i've described as specialists would come in it's possible that the aluminium could have been um placed onto um an uh inch meson strip
02:07:59 placed onto um an uh inch meson strip it's possible that there may have been conversation about using a steel angle as opposed to aluminium to achieve the um
02:08:06 the um the barrier in that way uh it's a kind of different arrangement we could have made i'm going to cut you off and i understand all of that okay it's all very useful can i just ask you to focus on a very specific point which is
02:08:17 specific point which is um i'm just asking you that where as you can see
02:08:21 can see about half of the depth of the cavity barrier doesn't abut the solid sub substrate like the concrete here but hangs below it would that compromise as designed would that compromise the effectiveness of the
02:08:33 that compromise the effectiveness of the cavity barrier if it would be securely fixed um i don't think so
02:08:38 think so right why is that uh because the cavity barrier
02:08:42 barrier uh the back of the cavity barrier as well as the bottom of the cavity barrier um will inhibit the passage of fire do you consider the aluminium angle to
02:08:53 do you consider the aluminium angle to be a suitable substrate against which to fit the cavity barrier as you can see is the case in your indicative drawing uh ideally not
02:09:04 uh ideally not but the arrangement that i've shown actually indicates on one of the drawings somewhere in my report that the yes it's it's a three-dimensional drawing
02:09:16 three-dimensional drawing it shows that the angle would be cut at intervals that's the shelf angle would be would have a slot in it for one of a better description at intervals along its length
02:09:29 along its length and that the um cavity barriers fixing would be directly to the concrete so the cavity barrier is not fixed to the angle the cavity barrier is fixed to
02:09:40 the angle the cavity barrier is fixed to the
02:09:41 the via its spike it's impaled on a spike which is
02:09:44 which is bolted straight into the concrete so would that require modification of the of the aluminium angle holding the window in place uh yes it would have to be cut but not a difficult task
02:09:55 difficult task right and let me just look at see if we can get this clear could you go to phyr 5028 please that's
02:10:06 5028 please that's page 77 so on some 15 pages in this document
02:10:10 document let's look at there it is that shows it that's it yes that's it i see so those just be clear for those watching those show do they the head details um showing the continuous window bracket
02:10:21 showing the continuous window bracket modified to accommodate the cavity barrier supports yes and please bear in mind this is a cut through it so it's a section and you'll see the second note down
02:10:32 and you'll see the second note down continuous aluminium window bracket that continues all the way along the top of the window would it be necessary to test whether the cutting into these brackets would compromise the strength or effectiveness
02:10:44 compromise the strength or effectiveness no it wouldn't be necessary to test that at all as long as the brackets are bolted to the wall either side of the um uh of the
02:10:56 of the um uh of the um spike which is the uh thing that the cavity barrier is impaled upon as long as the brackets are bolted
02:11:04 bolted to the wall either side of that there's no further testing or assessment necessary
02:11:09 necessary and would the result of the cutting into the aluminium angle mean that the back edge of the cavity barrier wouldn't tightly abut the surface against which it's fitted it would mean that you are correct
02:11:22 it would mean that you are correct my judgment is that um the the arrangement would be sufficient but i would want that
02:11:32 that to be verified by the specialist fire consultant and if they couldn't verify it we'd have to find it and if they could not verify it
02:11:41 it and satisfy building control having drawn their attention to it then we'd have to find a another arrangement
02:11:52 another arrangement do you agree with mr lam with uh his comment that in respect of your proposed solution fire could get behind the cavity barrier because the substrate that the aluminium angle
02:12:03 that the aluminium angle is bolted to is not flat because the concrete is not crisp and flat and straight as he says i think the
02:12:11 the the little gaps are going to be so small it would be insignificant that's my judgment as an architect
02:12:19 architect would another solution be to use a mineral wool cavity barrier here
02:12:27 a mineral wool cavity barrier yes
02:12:32 uh i i no i think the cavity barrier is correct
02:12:37 uh what about mineral wool packing to pack out the gaps where gaps were left in your solution um well i i i'm not so worried about the gaps
02:12:47 gaps but uh if that was to be packed and it it's possible it could be yet another layer of um protection then i would um seek to bolt the
02:12:58 then i would um seek to bolt the aluminium angle onto an uh an inchemescent strip and so onto the wall goes the strip
02:13:07 strip onto that because the angle is used the shelf angle and then the cavity barrier is fixed directly to the concrete through the slots now we talked about the aluminium angle here um what about steel what about the
02:13:19 um what about steel what about the placement of a steel angle at the head of a
02:13:22 of a at the head in order to act as a cavity barrier itself these are all the sorts of discussions that should have been taking place and at what point do you think they should have been taking place before
02:13:33 should have been taking place before um this is certainly not this is certainly not concept design so we're not into stage c we're not into stage d
02:13:41 stage d but we're into stage e and f1 here so before the documentation before the employers requirements documentation was issued these sort of issues should have been
02:13:52 these sort of issues should have been sorted
02:13:53 sorted and a a switch to a steel shelf angle not particularly difficult to do but harley mayweals well have said we preferred a deal entirely in aluminium we don't want to
02:14:04 entirely in aluminium we don't want to be introducing steel for whatever reasons
02:14:07 reasons and asked to find another way around it there are set there are a number of ways of solving a problem like this but the the time to do it is when there's time
02:14:19 time to do it is when there's time and before parties are committed uh with tender prices and if the steel if the metal angle was to act as a cavity barrier in itself uh would aluminium as a material
02:14:33 uh would aluminium as a material be permissible under adb um no it's not the
02:14:37 the adb is quite specific and it's a steel angle or
02:14:40 angle or or i think timber yes and in both cases i think it stipulates the dimensions of thickness right so in fact using an aluminium shelf angle as a cavity barrier itself would be
02:14:51 as a cavity barrier itself would be impermissible is that your opinion that's not possible um the reason being that aluminium melts at a lower temperature than steel now when it comes to examining the solution at stage e or
02:15:02 at stage e or f1 would you expect the reasonably competent architecture have taken the lead in proposing a design solution possibly not
02:15:15 proposing a design solution possibly not ensuring that the design solution is found yes
02:15:19 found yes and would you expect the reasonably competent architect to have engaged the involvement of building control at that point
02:15:28 i would i don't see building control as part of the design team i would wish to have my ducks in a row and then go to see building control and
02:15:39 and then go to see building control and say
02:15:39 say this is what we're proposing this is the basis
02:15:43 basis and what about engaging the client with the question about um the solution here would you expect the reasonably competent architect to go to his client and explain what's going on
02:15:53 going on i wouldn't expect the clients that i deal with wouldn't be particularly um pleased to have me coming and bothering them with issues like they said expect me to design something competently that complied with legislation
02:16:05 complied with legislation now i beg your pardon um that client been of course tmo yes and i'm saying that this should be done during that period of time yes later on
02:16:17 during that period of time yes later on a design and build contractor may well be interested
02:16:22 yes thank you now it looks from mr lam's evidence that we've looked at that he took a decision to move the position of the cavity barriers upwards we saw that because we compared the
02:16:32 the extract from the the studio e drawing with your figure 330 which showed the actual position of the pali cavity barrier up and you illustrated it with your
02:16:41 your with your hands is that change a design change which in your view should first have been discussed with the architect by studio by um harley or by mr lam
02:16:54 by studio by um harley or by mr lam well the the protocols for that are that the subcontractors drawings have passed the architect for comment um if they've got a good relationship
02:17:05 um if they've got a good relationship going between them there may well be a phone call on the way or a sketch sent by email but certainly at the time that the drawings came through um there is an opportunity to comment on
02:17:16 um there is an opportunity to comment on it and that should have been looked at by studio e yes i mean whether in fact there was or wasn't is it your opinion that there ought to have been a discussion between
02:17:26 between mr lam or harley and studio e about the change in the design
02:17:32 design well the the in my mind that follows mr lambing and saying hey i think i'm thinking of changing your cavity horizontal cavity barrier position over the window
02:17:43 the window possibly possibly not but it's certainly got to be picked up on the drawing which he did he put it on the drawing now let's go to har40s 3947 please this is an email chain
02:17:57 please this is an email chain in march 20 and 15 as we can see
02:18:04 and the first email on the page here is one from ben bailey to ray bailey attaching
02:18:12 attaching some images and when he says still going around in circles and it's copied to kevin lam
02:18:17 kevin lam but the one i want to show you is the second email in this chain which is an email from chris mort to ben bailey of the of the day of the same day 30th of march 2015.
02:18:29 day of the same day 30th of march 2015. uh and he says hi ben i've reviewed the drawing sent over and sketch a proposal to alleviate the issues raised by the bca also on the second page of the attachment i have highlighted
02:18:40 attachment i have highlighted a the weak link so to speak in terms of fire and i think the bco would also have noticed this
02:18:48 you see that yes yes and he goes on to say the proposal requires the installation of rh 25 gram 60 90 straight 60 product in two layers
02:18:59 two layers one at the head of the window aligning with the compartment floor and the other the top of the existing up stand therefore two layers of 60 minutes protection that overall would provide if tested over 120 minutes
02:19:10 over 120 minutes protection at the window locations uh this is just the heads of the windows is it
02:19:19 is it yes right um now i don't think i need the rest of the email for your view about this i just what i do want to show you is the attachment which is har403948
02:19:37 which is a drawing set now this is the first page of the drawing set where we can see the studio e drawing
02:19:46 and if we go to if you look at the right i don't think this is a strategy you're right this is no sorry this is a harley drawing right right you're quite right
02:19:57 drawing right right you're quite right if we go to the right hand side of it you can see that there's a manuscript and you can see where the cavity barriers are yes yes but i want to focus on the second page of this if we can just here we can see uh that um and this
02:20:10 just here we can see uh that um and this is a
02:20:10 is a harley drawing from august 2014 and this is
02:20:15 is revision e of the 3rd of march 2015. um here we can see that chris mort has put a squiggle cloud around the bracket holding the window in place
02:20:26 the bracket holding the window in place and has put the words weak link for fire do you see that yes and he is from side rice and he is from cider yes correct
02:20:34 correct and you can see the cavity barrier location there illustrated on this harley drawing do you consider that that there is a weak
02:20:44 weak link for fire in the location identified by mr mort for all the reasons that we've been discussing for the last 10 minutes yes and
02:20:55 yes and why is that could you just explain because
02:20:59 because there is um there's a cavity and there's no protection at the edge of the window and the gap between the window and the concrete the
02:21:11 between the window and the concrete the window
02:21:12 window here has moved out from the concrete so out from the face of the building and my report shows how the previous windows were installed within the line of the concrete so if
02:21:24 within the line of the concrete so if you just drop a vertical if you take the back of the angle i think everybody understands where the angle is
02:21:29 angle is that's fixed to the concrete if you drop a straight line down through the window the uh through the opening the original window position was behind that that's within the
02:21:40 that that's within the the concrete line this has gone outside and it's now created a gap between the top of the window and the concrete you can see that and the only filling to that gap or sealing
02:21:51 the only filling to that gap or sealing of that gap is the aluminium and the aluminium doesn't
02:21:55 doesn't satisfy the guidance of adb2 so there is a weak link for fire precisely as written here and beyond that weak link is fuel yes
02:22:06 and beyond that weak link is fuel yes thank you and the solution uh that you've identified at figure 3.30 in your report is the solution that you think ought to have been adopted is that right
02:22:18 have been adopted is that right yes yes now we don't see ourselves any evidence of this email having been forwarded to building control or building control being
02:22:30 building control being shown this attachment on which the words weak link for fire were indicated at the window head there that that's a matter of evidence my question is would you expect a reasonably competent architect
02:22:42 reasonably competent architect to raise this question about the potential
02:22:47 potential here for weak link for fire with building control
02:22:57 do we know a studio ever got this markup
02:23:02 drawing uh no they didn't i don't think well my answer then is if they'd have got the marked up drawing without a shadow of doubt well actually i wouldn't have even
02:23:13 well actually i wouldn't have even bothered to raise it with building control i'd have sorted it before i went to building control full stop let me ask the question in a slightly different way would you expect the reasonable designer
02:23:24 would you expect the reasonable designer whether it's studio e or ryden as the design and build contractor to have taken this question to building control
02:23:37 there's no point in taking the question to building control because it's an unacceptable weak link and a competent architect
02:23:44 architect or designer cladding specialist should know it's a weak link it's a non-starter it doesn't matter whether build control building actually that's the answer it doesn't matter whether building control passes or not that's the minimum standard they may have made
02:23:56 the minimum standard they may have made a mistake
02:23:57 a mistake our job is to comply with the guidance of adb2 if that's the route we're going it doesn't comply so i don't i even if the building control officer said fine you do it i wouldn't do it
02:24:09 you do it i wouldn't do it can we then move on and go to phyr zeros 28 at page 76
02:24:17 and i want to show you figure 3.38 on that page there
02:24:23 and we can see on the left hand side of this
02:24:26 this diagram here that you've indicated a breather membrane can you see at the top left-hand side of the picture yes the diagram
02:24:38 side of the picture yes the diagram it says breather membrane with a pointer arrow with a ball at the end of it identifying where it sits and you uh also say just four lines down from that breather
02:24:49 just four lines down from that breather membrane run between cladding bracket and vertical rail and dressed over horizontal cavity barrier you see that um does the placement of the membrane passing over the outer edge of the
02:25:01 passing over the outer edge of the cavity barrier have any impact on the functionality of the cavity barrier itself i don't believe so let me see if i can just explore that in order for the
02:25:12 just explore that in order for the intumescent strip on the leading edge of the cavity barrier to be able to expand into the cavity is it right that it shouldn't have any other building components obstructing that expansion against the
02:25:23 obstructing that expansion against the back of the cladding panel i i again these are issues for discussion with the specialists but i don't think so
02:25:31 so the the power of the expansion of the intumescence strip in in fire would just push the breather membrane straight out and and ram it against the back of um
02:25:45 and ram it against the back of um the surface to which it's seeking to close
02:25:48 close so i i don't think there would have been any issue there at all i see so you don't think that the um existence and location of a breather membrane
02:25:55 membrane would have inhibited the expansion of the intumescent it certainly wouldn't inhibit the expansion the issue is whether the that inch medicine strip would expand
02:26:07 that inch medicine strip would expand full stop um i think it would go snugly against the outer surface to which it's intended to reach i'm in no doubt about that can we then
02:26:18 i'm in no doubt about that can we then turn
02:26:18 turn to uh mr osborne's evidence he was osborne berry day 43 page 97 please
02:26:27 please and i'd like to go to line 16. uh he uh says uh
02:26:38 uh he uh says uh there and this is in the context of putting an epdm uh in in order to seal the angle brackets and to stop water leaking down and into the flats and then at line 16 he says in fact it
02:26:52 and then at line 16 he says in fact it starts at line 14. you couldn't penetrate the epdm with the fire break all the insulation so the epdm
02:26:59 epdm was put on and then the fire break was moved upwards to allow fitting of the fire break and fitting of the insulation and then he was then asked when you say
02:27:10 and then he was then asked when you say the fire break was moved upwards to allow the fitting of the fire break and fitting of the insulation do you mean is this on the columns we're talking about and he says no this is on the horizontal and if we go on to page 98
02:27:23 and if we go on to page 98 at line six he's asked the question does that mean that the positioning of the horizontal cavity barriers on the tower was slightly higher rose up you see that yes which he
02:27:34 rose up you see that yes which he answered yes and then he agreed um that um they'd be moved up from the position they'd originally been shown in the harley drawings you can see that just from lines 13 and
02:27:45 you can see that just from lines 13 and onwards
02:27:47 onwards now earlier on in his evidence mr osborne had explained that a sample panel
02:27:53 panel had been constructed for review that was we don't need to see it but that was page 97 at line 95. moving on from that at page 99 if we can just go back to that
02:28:04 just go back to that he's asked line two
02:28:08 oh he says at line two he says very early on in the project then a sample panel was completed i believe i was on the mask climber at the time
02:28:16 time graham was on the mask climber and several other people probably eight or ten people all came up to have a look at what we've done and then that was agreed and that's that's where it would be and that's
02:28:27 that's where it would be and that's where we work from basically that's what he says
02:28:30 he says now his point is that the cavity barrier had been raised up by about 10 centimeters from the position shown in the harley drawings and again that's page 99 at line 23 of
02:28:41 and again that's page 99 at line 23 of the transcript and he also said that it was either mr lam or mr ankle jones that had instructed that change that's page 98 line 24 of the transcript i've given you a huge so that's gone up
02:28:52 i've given you a huge so that's gone up from the position shown on harley drawings
02:28:54 drawings uh yes so it's gone up even further from the position shown on studio east drawings
02:29:04 well let's perhaps look at page 99 just to be just to be clear because i'm conscious that i'm now answering your questions rather than the other way around so i thank you help you um well it's not surprising i'm
02:29:15 help you um well it's not surprising i'm showing you an awful lot of transcript in order for you to swallow it in one go but the answer is your question is yes but let's look at page 99. um at page 99 uh line 23
02:29:30 uh he says 10 centimeters so that's that he's given the measurement there line 25 approximately how far from the head of the window was let me go over the page please that
02:29:43 was let me go over the page please that cavity barrier then roughly and he says i can't remember now perhaps it's easier to do this by way of a picture
02:29:52 a picture uh mr osborne was shown a photograph and we can look at that at har401524
02:30:00 just have that photograph up there now that's a photograph of the building during construction as we can see and we can see the cavity barriers
02:30:10 barriers in black uh horizontal and vertical lines do you see interestingly you can also see the slots cut out of them for the vertical channels that are going to be installed yes you can yeah that's absolutely right
02:30:22 yes you can yeah that's absolutely right now of that photograph mr osborne um gave uh some um description of page 96 page 116 of his evidence we can just look at that
02:30:36 and go back to page 116 line 12 um he's shown this photograph and he's asked uh
02:30:47 and he's asked uh at one six i'm sorry 166 my fault on six six he's asked at 9 12.
02:31:01 at 9 12. uh line uh six he's asked so these photographs would get a sense i think is that right of how high above the windows those cavity barriers were would you agree
02:31:12 cavity barriers were would you agree answer i do so we can see there that they are further away from the windows than allowed for in the drawings answer correct now i've given you an awful lot to swallow
02:31:23 i've given you an awful lot to swallow there mr hyatt and i'm sorry about that but do you agree looking at this photograph and and the evidence um that i've shown you in the transcript that the cavity barrier actually installed
02:31:33 installed is higher than the position even as shown on the harley drawings i believe that that was it looks like it from the photographs but i have also measured on-site
02:31:45 but i have also measured on-site sample cavity barriers and i found them to be higher
02:31:50 is that a design change which in your view should have been discussed with the architect the lead architect
02:32:00 the installation should be as the approved drawings and any departure from it
02:32:05 it should be cleared so yes and is it your opinion that that change should have been recorded in drawings
02:32:17 when we make changes on site we sometimes issue a site instruction that might carry a sketch with it um and it may not be necessary to go back to change the drawings
02:32:29 back to change the drawings but um the principle of but the as record drawings should show the correct arrangement uh the as-built drawings at the end i was going to ask you yes if that's what you're going to ask yes they they should be shown correctly on there
02:32:41 they should be shown correctly on there yes at some point whether it's immediately or in production of the as-built drawings the alteration of the position of the should have been recorded horizontal cavity barrier should have been recorded
02:32:52 cavity barrier should have been recorded in drawings yes but more to the point the drawings are there to ensure everybody understands what they're doing and that the building is compliant
02:32:59 compliant a change like that should have been fed back through the architect and back through building control and or exoga
02:33:08 exoga would you in principle have been supportive of this mock-up construction of the cavity barrier insulation and panel placement that seems to have been undertaken by osborne berry on site
02:33:20 undertaken by osborne berry on site and then considered by the 10 or 12 people or say who'd seen it
02:33:27 would you agree with it no why is that because it it departs from the architect's drawings
02:33:38 the architect's drawings it it would they should have spotted it departed from the harley drawings and it departs from adb
02:33:46 adb too and there should have been people there who understood the way in which the design was intended to comply with adb2 and could have said this is just a non this is just not
02:33:58 this is just a non this is just not right
02:33:59 right would consideration of the mock-up need to be had by reference to studio e's drawings
02:34:04 drawings included in the employer's requirements
02:34:08 would you need to put the mock-up next to the employer's requirements drawings and
02:34:12 and and consider the former in light of the latter
02:34:16 latter i haven't quite got the date of the mock-up in my mind the mock-up is of course after the employer's requirements was the is the mock-up was the mock-up done after
02:34:27 done after um the harley drawings had been issued yes it was it's done on site during construction well that takes us back to the comment i made yesterday which is that
02:34:38 which is that the the difference between the architects drawings and the harley drawings should have been highlighted and either the architect's drawing should have been corrected
02:34:49 drawing should have been corrected or there should have been some authority to to depart to the harley drawings but either way round um if the harley drawings are by then in currency there's where the mistake lies
02:35:02 currency there's where the mistake lies but if they're in currency and the installation of the mock-up doesn't even comply with those then that should be raised again i see so i i don't know i don't think that the the mock-up
02:35:14 know i don't think that the the mock-up team would have had one set of drawings from the architects and one sort of drawing from harley
02:35:18 harley harley's drawings needed to be right they were the authority and it should be checked against them and in your view should studio e have
02:35:29 and in your view should studio e have been involved in reviewing the mock-up
02:35:33 if they're retained if they're debated i think they should have wanted to have been there and expressed concern if it was going ahead without
02:35:44 concern if it was going ahead without them i think that ryden should have absolutely wanted them there and shouldn't have contemplated having a mock-up without them there i don't know whether they were there or not i think i take it from your
02:35:55 not i think i take it from your last answer but one that you are of the view that constructing a mock-up of this type uh took place far too late in the process
02:36:06 and when i say in the process i mean in the design process not necessarily the market can have a whole host of useful um purposes um so
02:36:20 purposes um so i'm thinking back to when we did the the last mock-up i saw was the up to stadium and we did that just to get a sense of visually what it would look like and we wanted to see it there is no reason why all of these
02:36:32 there is no reason why all of these problems
02:36:33 problems couldn't have been sorted out from drawings and indeed there's every reason why they should have been so it doesn't need the mock-up to sort out the problem the fact is that the
02:36:44 out the problem the fact is that the the markup illustrates that they have well the markup illustrates that they've misunderstood the drawing and misapplied the drawing well that's really my point that if you're going to make a change like this whether through
02:36:56 make a change like this whether through a mock-up or through a drawing at this stage in the process it's too late because it's too late to address any
02:37:01 any issues with the design well they can make a change but they've got to get the authority for the change right and with that authority include taking formal authority from the ultimate client the tmo in this case or
02:37:12 ultimate client the tmo in this case or not
02:37:16 no because it's a technical issue of compliance the tmo expect their team to deliver a competent building that's complying with the building regulations they're not
02:37:27 building regulations they're not checking their work the the team had uh the responsibility to make sure that it was compliant
02:37:35 thank you i now want to turn to a set of questions about the cavity barrier strategy at the jam condition the jam column condition you know what i mean by that i do yes
02:37:47 you know what i mean by that i do yes yes
02:37:47 yes um can we start by looking at p h y r uh five zeros 28 please at page 68.
02:37:57 this is figure 3.33 of your report typical detail one jam stroke
02:38:04 stroke column interface and here am i right in thinking that you have provided a detail a proposed detail for the jam stroke column condition which shows a bespoke
02:38:16 which shows a bespoke shaped corner piece yes that's correct and just to be clear for those listening it's a piece of vertical cavity barrier which is to be fixed back to the structure of our brackets to fill to
02:38:27 structure of our brackets to fill to fill
02:38:27 fill up fully the residual cavity at the window jam yes and i think you also say that in the alternative if you couldn't do it that way then you
02:38:39 if you couldn't do it that way then you could fill the residual cavity with mineral
02:38:41 mineral wool under compression correct and we also see a pro the proprietary vertical cavity
02:38:53 pro the proprietary vertical cavity barrier fixed to the structure via brackets in this picture in this diagram don't we
02:38:57 don't we yes um if we turn to figure 3.27 on page 54.
02:39:02 54. if i may missed a minute that's in the position that i've shown it as well that that um rectangular when it's not in the position shown by either studio or harley no i understand that
02:39:12 that if we go to page 54 for the moment and look at figure 3.27 on that page yes just to be very clear we can see the location of the vertical cavity barriers
02:39:24 location of the vertical cavity barriers at the window jams on the cross-section of a typical floor here can't we yes um and could you just help us explain by reference to this figure figure 3.27
02:39:36 um and figure 3.33 that we looked at and 3.34 if we need to why it is that you consider that two vertical cavity barriers per column are
02:39:47 vertical cavity barriers per column are necessary
02:39:50 um the vertical cap the first point is the vertical cavity the yellow vertical cavity barriers um are only for the depth of the window
02:40:03 um are only for the depth of the window they don't go from floor to floor they just go from the top to the bottom of the window and they are necessary to seal the gap between the window frame and the column and as you can see if we
02:40:14 and the column and as you can see if we take flat three corner column there is two junctions of windows to the column there's a window that is
02:40:25 there's a window that is on the facade that is between d1 and d2 columns and the window that's on the facade between d1 and c1 so there's two windows two sets of windows meeting the column
02:40:37 sets of windows meeting the column each of those junctions need to be sealed with a cavity barrier yes and it may be easier to do this by reference to
02:40:48 reference to figure 3.34 on page 71 of your report if we can just turn to that we may get an even clearer illustration of that there yes that is correct and could you just
02:41:00 yes that is correct and could you just point out to us in on that diagram uh what it is you're proposing there well
02:41:07 well you can see the window uh this is a a plan so you're looking so you're looking people may not understand down through the building yes as if we've cut a slice
02:41:18 we've cut a slice through the building yes at the window level
02:41:22 level and so that slice goes straight through the window and if you look at the window there all the little lines denote the
02:41:29 the various parts of the aluminium window and then you can see two um lines moving out to the right of the page
02:41:38 the page triple lines together that's the double glazing
02:41:41 glazing is that clear yes that is just and then the column is on the left yes um with the yellow um surrounds to the grooves that run up the
02:41:52 surrounds to the grooves that run up the column so there's the column face coming chamfered to the point of the meets the window and then returning it right angles to the window and so the inside of the flat is at the top
02:42:03 inside of the flat is at the top the outside of the flat is at the bottom the cavity barrier that's rectangular you can see the spike dotted as a dotted line
02:42:12 line that's been impaled onto that spike and it is as close to the edge of the cavity as it's possible to put a proprietary product that's purchased there's then a gap and
02:42:25 that's purchased there's then a gap and that gap has to be filled i believe that it would be possible to persuade um or to attract cavity barrier suppliers to make special cavity
02:42:36 barrier suppliers to make special cavity barriers
02:42:37 barriers to fill that gap if not it would need to be packed with something like mineral wool and looking at this diagram do we take it
02:42:48 looking at this diagram do we take it what you just told us that that gap wasn't filled at all on the as built on the building has built
02:42:56 built yeah the model um shows that clearly there is no um filling in there at all so the gap between the window and the concrete i'd refer to as being up to 120
02:43:08 concrete i'd refer to as being up to 120 millimeters existed vertically for the height of the window and then there was a passage straight into the cavity there was no protection of any sort
02:43:17 any sort until the one vertical cavity barrier that did exist on the columns was reached and that could be
02:43:25 could be right around the other side of the column joining the next window do you consider that the guidance in approved document b required this gap to be filled in the way that you've identified
02:43:36 way that you've identified it's clear yes could we then just go back to figure 3.33 at page 68 of this report or this part of your report
02:43:48 this report or this part of your report um we can see um there
02:43:52 that again there is a breather membrane you see on the right hand column breather membrane taped and sealed onto epdm
02:44:02 epdm and then below that on the left hand side also
02:44:06 side also at the very bottom breather membrane uh identified at the leading edge
02:44:14 is it the case that the proper functioning of the breather membrane would need an air gap between the corner piece and the cladding looking at the one on the right hand side
02:44:22 hand side yes and instead of the breather membrane being pressed up against the rear face of the cladding panel there need to be a gap
02:44:40 no it would it would fill right the way up to the to the edge of there yes and is that a problem given that uh the proper functioning of the breather membrane no i don't yeah so
02:44:52 membrane no i don't yeah so i don't think so why not because the gap the the the gap is so infinitesimal again these are all issues for discussion as the design develops but the gap is
02:45:03 as the design develops but the gap is infinitesimal so i don't think that that's a problem right that may answer my next question which is this if this corner pieces you've designed it were to be installed in the way you've shown it
02:45:13 shown it do you think that it wouldn't fill the entirety of the cavity because of the presence of the membrane and the way that it works
02:45:21 no it's shown to to to fill it
02:45:26 tightly um the the main purpose of it is is at the top where the junction is with the window is to stop the passage of fire
02:45:37 the passage of fire through there into that zone i i'm as i say it's an indication for discussion i i'm happy that it would form that and there may be refinement to it
02:45:50 that and there may be refinement to it other specialists may have comments should the should the breather membrane allow water to trickle down the outside face of the membrane so where you've shown it
02:46:00 shown it uh on the ga in the gap between the top of the membrane and the
02:46:08 the um the edge of the window the jam of the window
02:46:15 water trickling down um
02:46:20 there's going to be damp in that zone but it's
02:46:27 it it hasn't in my mind got the same function as the um the horizontal cavity barrier uh gaps behind the main part of the um the
02:46:39 behind the main part of the um the cassettes um but i i see where you're going with that i i can only say it would need further discussion right i mean you can and the point i'm really putting to you is that this is an imperfect design because of the breather
02:46:51 imperfect design because of the breather membrane
02:46:52 membrane and the fact that it would if it had to be packed tightly and it wouldn't allow water to trickle through and that's a design defect possibly it may there may be even discussion about leaving it out
02:47:04 discussion about leaving it out i would i would need to take specialist advice on that i see now of course this is a bespoke piece as you've as you've explained would you expect a specialist uh subcontractor to design this element
02:47:16 subcontractor to design this element in instead of the reasonably competent architect in the position of studio e
02:47:29 these well the word there is specialist the specialists con subcontractor they their literature states with confidence
02:47:40 literature states with confidence their capabilities
02:47:44 amongst those is of course installation and implicitly an installation which is compliant
02:47:53 compliant with um with code it's a problem that has to be solved somewhere down the line i've already said i think that at tender stage the principles should
02:48:06 at tender stage the principles should have been resolved those principles i think should then have been
02:48:12 have been refined by the subcontractor as they move on into fabrication this is an example of fabrication um alternatively and this is back to territory of yesterday if there was something fundamentally
02:48:23 if there was something fundamentally wrong i would hope and expect that the subcontractor picked it up but the intent should have been there on the architect's drawing the problem should have been identified and the
02:48:34 should have been identified and the attention had been there there may have been discussion as to exactly how to do it
02:48:40 would the reasonably competent architect when proven designing through to stage e or f1 have addressed this problem and
02:48:52 have addressed this problem and produced a bespoke solution such as the one that you are recommending think so
02:49:01 so the answer is yes i did make it clear that tenders can be sought with varying degrees of information at various stages of the process
02:49:12 at various stages of the process it would have been possible to have obtained to have garnet for tenders at the end of stage c or stage d in which case it would not be there but the in this case the tmo appointed
02:49:24 but the in this case the tmo appointed the architect to take the work through at least to the end of f1 on that basis i believe it should have been there thank you now i want to put a countervailing argument to you
02:49:36 countervailing argument to you is it possible would you be of the opinion that the design of bespoke pieces such as this if designed in and
02:49:44 in and specified by studio e at that stage pretender
02:49:50 would you be of the opinion that that would amount to the illegitimate or perhaps undesirable curtailment of the subcontractors freedom to develop the design
02:50:03 no because um the subcontractor can the the main the tendering contractor can have amongst the notes for discussion and alternative arrangements and could
02:50:15 and alternative arrangements and could say here's our tender but we wish to discuss the following um or they could raise it without having qualified it at the beginning later on after being appointed they could say we're looking at this in a
02:50:27 could say we're looking at this in a different way we want to discuss it so it doesn't preclude that
02:50:33 thank you um i want to turn now to the topic of relating to cavity barriers
02:50:41 barriers around the vertical cladding rail which you
02:50:44 you have explained to us in your model because we start please by looking at b l a s 608
02:50:54 at page 57.
02:50:58 now on that page is a photograph
02:51:05 uh with two rings in it can you see that the left i certainly can yes and this is just to be clear figure 8.64 from barbara lane's report yes
02:51:16 from barbara lane's report yes and this is a photograph i think of the spandrel condition with the column to its right
02:51:21 its right uh if you're looking at it from the camera's point of view and there's a black line down the middle and that that's the cladding rail and if you look inside the blue circle there you can see what i think you called the uh the lugs
02:51:33 what i think you called the uh the lugs um
02:51:33 um or the bolts on which the cladding panels are to be because we use the word toggles
02:51:37 toggles these are the way you use poles yeah and is it right there behind the rail uh you can see a quantity of insulation and below the insulation you can see the cavity barrier that is correct and that's got a silver
02:51:49 that is correct and that's got a silver top and a black face and may i draw your attention if you look at the junction of the the right hand part of this
02:51:57 this eve of the circles if you look at the junction of the black which is the channel
02:52:02 channel with the silver which is the face of the insulation you'll see a yellow strip yes that yellow strip is where they have pre-cut
02:52:13 pre-cut into the
02:52:16 into the insulation so that the it fits it accepts the channels
02:52:25 i showed that on the model when we started on monday the notches sort of cut yes yes thank you uh
02:52:37 and that then leaves a gap within the cladding rail the u-shaped cladding rail doesn't yes yes now
02:52:45 yes now mr lam was asked about all of this in his evidence and particularly whether he considered this gap in the cladding rail uh and let's look and see what he says it's day 38 please at page 113
02:53:05 and if we look at the top of the page mr lam is asked by ms grange line two yes but you've still got the break in the cavity barrier where the rail goes do you agree and
02:53:17 where the rail goes do you agree and then he says at line four yes but the rails are continuous so there's no alternative and if you look a little bit further down that page to line 11 he is asked why didn't you ever give any
02:53:29 he is asked why didn't you ever give any consideration to the gaps that would be created by the cladding rails as they went through the cavity barriers answered there were no gaps it was cut tight
02:53:38 tight to the cladding rails see he says that and then he he is asked yes but the cladding rail itself was a channel through which the cavity barrier
02:53:49 channel through which the cavity barrier did not fit does that make sense it didn't go through the middle of the cladding rail yes the front is yes and then um he's asked sorry can i read that
02:54:00 um he's asked sorry can i read that again
02:54:00 again it's that's 16 yes but the cladding rail itself was a channel for which the cavity barrier did not fit
02:54:08 not fit now the cavity barrier was cut around the back of the channel that is correct yes yeah and then um ms grange asks him we'll come and i'll show you some pictures and i think in
02:54:19 show you some pictures and i think in paul heights report we get and she's interrupted by mr lam he says i mean this is normal practice and then she asks him it's normal practice to cut around the
02:54:31 it's normal practice to cut around the cladding rail is that what you're saying and if we go over the page
02:54:36 he says at line one that's right as long as it's tight on the inside you can do no more on the outside because it's a cladding it's a continuous joint yes and then she asked but wouldn't it have been possible to put a piece of cavity
02:54:48 been possible to put a piece of cavity barrier inside the u-shape of the cladding rail so that you have a continuous cavity barrier along the spandrel answer but that would be exposed to the outside world then
02:54:59 outside world then question no it was inside the rain screen okay i think we need to have a look at the detail yes we can do that now um you know again i'm sorry i'm going to show you
02:55:10 again i'm sorry i'm going to show you some more mouthfuls of this but let me just do that if you go to page 151 and let's look at line seven miss grange asks mr lam this question uh that's why i'm asking
02:55:22 this question uh that's why i'm asking whether anyone ever thought about whether or not that was an unsatisfactory arrangement and that there ought to be some consideration of dealing with that vertical gap through the cavity barrier
02:55:33 the cavity barrier and in line 12 he says in my experience it's not something that's ever done you don't fill it with an insulation but maybe the argument is that the cavity barriers are to stop the spread the unseen spread of flame if
02:55:45 the spread the unseen spread of flame if a flame gets into that black zone you can see it from between the gaps in all the panels from the outside question really answer yes
02:55:56 uh and um
02:56:01 at line 23 i think i can skip over the next exchange he says all i'm saying is that in my experience it's not normal to try and put a cavity barrier inside
02:56:13 to try and put a cavity barrier inside that rail
02:56:15 that rail so that's his that's his oral evidence and his view having been pressed quite rigorously on it um can we then look at your report at uh page 28 phyr502
02:56:26 uh page 28 phyr502 please at page 80 phyr 5028 page 80.
02:56:34 and here we have figure 3.41 which is typical detail for plan through plan detail through spandrel straight column interface where column aligns with compartment wall you see that yes and you've got your uh
02:56:48 you see that yes and you've got your uh cladding rail there in the bottom right hand
02:56:51 hand corner of the diagram you see that yes and i think you've got an arrow pointed to cladding vertical channel there that's the fourth direction at the bottom and the toggle going through it yeah with the toggle
02:57:02 going through it yeah with the toggle going through exactly or lug as i think i wrongly called it um if you um look at that um i'm interested in the bottom right hand drawing there
02:57:12 you can see i think a zoomed in diagram of this on page 81
02:57:18 just for the inquiries benefit this is a cut through the building that the previous drawing if you don't mind we'll just go back to page 80. that is a cut through the building
02:57:29 that is a cut through the building underneath the drawing that we were looking at previously which was cut through the building at window level this is cutting through the spandrel panel below the window yeah this is exactly this isn't about
02:57:40 yeah this is exactly this isn't about the windows no very difficult for people to visualize that's where these channels yes we're on the we're on the topic of the vertical channels not the window yes going back if we can please to page
02:57:51 yes going back if we can please to page 81
02:57:52 81 and look at figure 3.42 and we can see a close-up
02:57:56 close-up as it were of the typical cladding joint at spandrel and you can see that the vertical cladding channel is is essentially an upside down u-shape here
02:58:08 upside down u-shape here and at the very bottom of the diagram is it right that there's an aluminium rain screen cladding depicted there returning into the vertical cladding channel it comes in and up yes
02:58:20 it comes in and up yes and either side of the channel there are open state cavity barriers abutting the vertical
02:58:26 vertical uh vertical cladding channel you see that
02:58:30 that is that right um
02:58:35 yes uh well where it says horizontal open state cavity barrier that black dot at the end of that that line
02:58:43 line is the intumescent strip at the edge of the cavity barrier which goes all the way to the top of the picture yes yes so cavity barriers would be
02:58:54 yes yes so cavity barriers would be abutting the cladding rail as you've shown it i think the cavity yes the the cavity barrier was in we showed it with the model the
02:59:06 was in we showed it with the model the cavity barrier is pushed onto the spikes and it has notches cut out of it to receive the channels which then fit neatly into the notch
02:59:19 neatly into the notch and i do beg your pardon you're going to want to come back to it later i think i misdescribed the um the insulation on dr lane's drawing earlier i won't interrupt now but we may
02:59:30 earlier i won't interrupt now but we may want to go back to that to just correct that oh well let's let let's do it now then while we have it otherwise we could have dr lane's drawing back okay i do apologize it was a mistake i made do you mean doc doctor names photograph
02:59:41 do you mean doc doctor names photograph um yes that will be bl there it is yeah i
02:59:45 i i it was silly of me i drew attention to the yellow strip along the edge of the um the black channel
02:59:53 channel and said that that's where the insulation has been pre-cut but it was only the cavity barriers that were pre-cut to receive the channel as you can see the the silver at the bottom of the picture
03:00:04 picture uh that silver is is the is the cavity barrier being cut and i don't know why that yellow strip exists there at all well i was going to ask you about that yeah i'm sorry i just skipped over it no
03:00:15 yeah i'm sorry i just skipped over it no it's interesting i mean in fact is it the case it looks like the case that actually the uh the yellow strip is is it the exposed uh
03:00:23 uh pir or phenolic where the person who's cut it has exposed pir behind the silver foil
03:00:35 has exposed pir behind the silver foil the aluminium foil facing this being insulation
03:00:43 actually i don't know what that is well that's what i'm suggesting to you i know you didn't take the photograph and work there at the time but that is that is a possibility that is actually exposed
03:00:55 actually exposed pii it doesn't look like pir to me actually
03:00:59 actually it looks like um uh mineral wool that top piece of that so i i'm not sure what that is there
03:01:10 i've not i may have seen this photograph before but i it looks strange to me i think that there's further inquiry needed into what that photograph is uh right but sticking with it then i
03:01:22 uh right but sticking with it then i think you could we certainly agree with each other that at the bottom of the rail there is uh the um horizontal cavity barrier with the black face being the intumescent strip that's correct which is um at a
03:01:33 that's correct which is um at a horizontal level overlipped by um a foil yes yes that is correct yes i'm sorry to have distracted us on the other point no that's okay well um we've clarified that i think there
03:01:46 um we've clarified that i think there may not be a mystery about the the yellow horizon yellow vertical line there
03:01:51 there um i'm not sure it necessarily matters can we then go back to the zoomed in diagram yes of the vertical channel at page 81 in your report
03:02:02 your report yes p h y o five zero twenty eight i think yes there it is uh and and we can see that there and you show the cavity barriers are butting the cladding rail
03:02:13 cladding rail correct yes now if if you were to imagine that the cladding panels were not indicated is it right that there would then be a gap running the entire way down the vertical cladding channel
03:02:25 vertical cladding channel yes first of all the gray it says light gray indicates the zone that the open state cavity barrier will close up so i now imagine there's been a fire and the intumescent strip has
03:02:36 fire and the intumescent strip has expanded
03:02:37 expanded and the cavity barrier has come out to touch the back of the cladding yes okay the pink zone indicates where that
03:02:46 that intimacy strip would not have gone it may have strayed a little into the pink but essentially it's going to go outwards
03:02:54 outwards it certainly won't go around the corner exactly around the corner but we're going to come to the pink okay in a moment but but am i writing just focusing on my question that the cladding
03:03:05 cladding panels if they weren't indicated on this drawing if you took them away that that would create a gap running the entire way down the vertical channel yes there's a slot right right
03:03:17 channel yes there's a slot right right yes
03:03:17 yes exactly that's the gap we saw in the photograph in dr lane's report yes a moment ago yes correct now then um we can see that the cladding returns into the gap as you can show and you fit it it goes into the gap
03:03:28 it it goes into the gap and it hooks over the toggle it hooks over the toggles yes and you've shown a remaining gap and you've called it the residual flanking zone i think
03:03:40 flanking zone i think yes that's still a gap yes yes now um mr lam offered in his evidence uh a reason why that gap was not um addressed and that as he says may have
03:03:53 addressed and that as he says may have been because if a flame gets into that gap there
03:03:56 gap there then you can see it from between the gaps in all the panels from the outside that's the part of the transcript i showed you am i right in thinking that actually you wouldn't be able to see that flame at all
03:04:08 all if a flame got into the pink areas you wouldn't be able to see it from the outside would you or would you uh no because the um the panel uh conceals it but you may see
03:04:20 the panel uh conceals it but you may see flickering shadows of you know it's a flame is a light so if it was dark for example you would see between the returns of the cassettes where they
03:04:31 returns of the cassettes where they both go back and over the toggle you would see light coming out from there in the dark in the daytime no you wouldn't see the flame right so to what extent with the
03:04:42 right so to what extent with the gap in which the flames would appear be masked by the cassettes
03:04:49 it would be completely masked if the flames
03:04:53 flames restricted themselves to just the the pink
03:04:58 pink i think they would um
03:05:02 what the flames do they would blow out in you know into the area behind the toggle between the toggle and the channel
03:05:09 channel um but in principle the the fire starts within the cassette and cannot be seen
03:05:17 seen yes thank you mr chairman we are um still in this topic but it is certainly a convenient moment for the break now i think
03:05:26 think yes um it's it's not a perfect moment in the questions but it's a perfect moment in the day i think it is isn't it mr hyatt i think we ought to have a break now so we'll stop now for that everybody
03:05:37 so we'll stop now for that everybody else would like a breakout certainly fall in well we'll have one we'll um we'll stop now we'll resume at 10 past two please thank you and again please don't talk to
03:05:49 thank you and again please don't talk to anyone about evidence when you're out of the room
03:05:51 the room all right thank you very much
03:06:11 ten past two please
03:06:34 you