England and Wales High Court (Technology and Construction Court) Decisions

IN THE HIGH COURT OF JUSTICE
QUEEN'S BENCH DIVISION
TECHNOLOGY AND CONSTRUCTION COURT

		Royal Courts of Justice Strand, London, WC2A 2LL
		July 2013

 


Mr Justice Akenhead:

Introduction

1. This judgment relates to all aspects of liability and contribution and to quantum in relation to the steps and seats claim. A further judgment will follow which will deal with quantum relating to the ceilings claims.
2. These proceedings related to the new Museum of Liverpool constructed between about 2007 and 2011, it being open to the public in July 2011. It has a dramatic and interesting design with sweeping roofs clad in aluminium and with what might be described as half amphitheatres comprising concrete steps and seats at the north and south end. Internally, there are four levels with two types of suspended ceilings, "SAS" and "Armstrong" ceilings. The building is located beside the Mersey between the Albert Dock and what are called in Liverpool the "Three Graces", namely the Royal Liver, Cunard and Port of Liverpool buildings, which many think grace the skyline of the western edge of the city. The Museum is broadly a history and cultural museum which exhibits historical artefacts and objects which relates to Liverpool. One of the prize exhibits is a pair of dark glasses worn by John Lennon of the Beatles. It attracts hundreds of thousands of visitors a year.
3. There are essentially three areas of complaint: the steps and terraces and the SAS and Armstrong ceilings. There were collapses of the SAS ceilings in mid-2011 and the Armstrong ceilings have been inadequately installed. The steps, seats and terraces have suffered from overall design problems and decisions which resulted in the works being suspended from about January 2010 to the opening of the building, with the undoubted problems still not being remedied.
4. The claim is by the Claimant (whom I will call "the Museum") against its architect, AEW Architects and Designers Ltd ("AEW"). Certain aspects of liability were admitted very shortly before the trial by Counsel on behalf of AEW. As for the remaining aspects of liability, there have been no further admissions of liability by AEW notwithstanding important concessions made by its own architect expert when giving evidence. AEW has brought in as a third party PIHL Galliford Try JV ("the Contractor"), which was retained by the Museum to carry out the construction works together with certain elements of the design.
5. I made clear on the first day of the trial that I was very surprised that the case had not resolved itself in the light of the admissions of liability made by AEW. I even asked all three Counsel what the Court could do to facilitate settlement. Notwithstanding this and in spite of the further concessions made by AEW's architect expert, there remain live issues of liability and limited agreement between the parties as to 50 main heads of quantum. This was all the more surprising because the Claimant took the unusual step of making an open offer on the fifth day of the trial in relation to each and every head of claim and specifically invited responses; no clear responses were provided. I was informed by solicitors for AEW following the final speeches that "meaningful settlement discussions" were proceeding between the parties but I have more recently been informed that, although AEW and the Contractor consider that such discussions are continuing, the Museum does not. I have therefore resolved to produce the judgment. Of course, the Court cannot be and is not privy to what has been happening on a privileged basis between the parties but I am disappointed that there has not been a resolution of the case by the parties.

A Brief Description of the Elements of Work in Issue

6. The Steps, Seats and Terraces, which I have described as half amphitheatres, provided an external link between the pavement level and the first floor level of the building, albeit that the main access is at ground floor level. If looked at from the pavement level what one sees are steps going up on the right with two sets of handrails obviously for people to walk up and down. To the left going up, there is a continuation of the steps until they reach a junction or valley where they are intended to connect to seats which come in at an angle from the left. The stairs are interspersed at two levels by wider terraces, presumably so people can walk along them. At the top of the stairs, there is a slab terrace which leads to one of the entrances to the main building. A primary issue in the case relates to the junction between the steps and the seats. As eventually designed and constructed, the steps and seats are constructed in white acid etched finished precast concrete. The steps are pitched at 19.5° and the seats at 26°, approximately. The steps have a 410 mm tread and 150 mm rise whilst the seats are 620 mm wide and 300 mm as a rise. This asymmetry in the intersection or valley meant that a variation in dimension on one slope would have a different effect on the abutting slope. It should have come as no surprise to the designers that special arrangements at least had to be made at the valley or junction.
7. The steps and seats are supported from below by structural steel onto which were laid precast concrete planks laid in a series of slopes and flat areas above which were placed concrete ribs going from top to bottom over which was placed a single layer pvc waterproofing membrane. On top of these, the precast concrete steps and seats were located. There were various mechanical measures taken to prevent the steps and seats sliding down the slopes. A comparable arrangement was made for the upper terrace with block upstands being placed on precast concrete beams overlying steelwork with the block upstands and the remainder of the terrace covered with membrane on top of which paving type slabs were placed. The drainage of rainwater was clearly intended to be through gaps between the various slabs and step and seat components through to the level of the eventually concealed waterproofing membrane.
8. The SAS ceilings were installed mostly on slopes. They were suspended ceilings, that is suspended from the underside of the floor or roof above and they were supported by what is called ERCO lighting track. These tracks comprise metal angles which include at the bottom clips which hold the suspended ceiling panels in. The Armstrong ceilings were used in the main circulation areas and in peripheral gallery areas of the Museum and they are supported off a grid which is attached to the roof or ceiling above; the ceiling panels are supported off inverted T bars which themselves are not fixed to the grid and also off the ERCO lighting track.

The General Chronology

9. In or about 2005 or 2006, the Museum retained a number of different professionals (project manager, structural, civil and mechanical and electrical engineers, architects and cost consultants). The architect was originally a Danish firm 3X Nielsen A/S which sub-contracted most of the architectural work to AEW. The engineers were Buro Happold. Between them, the various consultants produced various designs and specifications. Tenders were sought from contractors in about March 2007 and the Contractor (in this case) was duly appointed, the Contract Sum being £41 million. Work started in the spring of 2007. An IT protocol was agreed between the consultants whereby documents, such as designs and instructions could be assessed and checked and approved.
10. By June 2007 AEW took on the role of Contract Administrator and was clearly closely involved with most of the design decisions as well as the administration and running of the construction contract. In particular Mr Hiscocks was involved. AEW was intimately involved with the production of design drawings from early 2007.
11. By about October 2007 the Danish architects dropped out and AEW was engaged directly by the Museum as architect. The formal deed of appointment was actually dated 5 November 2008 and contained warranties that reasonable skill, care and diligence had been and would be exercised. I will refer to this in detail later. As well as its own design responsibilities, AEW undertook the lead and coordination role in relation to all the other design team members such as the engineer. AEW also undertook an inspection role.
12. There were regular meetings involving the professional team as well as members of the Museum staff. There was a Change Control Procedure in place and there were over 100 Change Control Meetings. This Procedure involves a detailed process by which each change needed to be approved. It was instituted for a number of reasons, not least of which was cost control but also the involvement of the Museum senior staff to ensure that they approved the changes from an aesthetic as well as from an operational standpoint. There were also Design Team meetings attended by the professional team members as well as by Museum staff as required. In addition, there were monthly Principals meetings attended by the Contractor, the professional team and by senior representatives of the Museum. There were also Project Team meetings. Sharon Granville was the Executive Director of the Museum and she had a detailed involvement at all stages. This was a project in which the Museum and its senior staff, unsurprisingly given the importance of the building, took a close interest in and they were involved in detail from beginning to end.
13. The original design concept of the steps and seats was that they would meet and align very precisely in a valley running between the two adjoining elevations of steps and seats. In the latter part of 2007 it became apparent that there was or might well be a clash between the underlying steelwork design and the design of the steps. This was resolved later that year by adapting the steelwork so that the precast plank units which were to sit on the steelwork were supported at different levels to overcome the difference between the height of risers underneath the seat units (300 mm) and the height of risers underneath the step units (150 mm); specially shaped concrete units would therefore be required to fit over the steelwork. In 2008 AEW changed the design so that the precast units were supported on the concrete upstands which in turn were cast on to or in some cases as part of the precast planks albeit without metal fixings. This redesign required the step and seat units to interlock with the whole bank of units acting together but being prevented from sliding down the slopes by lugs formed on the underside of the lower units which fitted into a recess in the upstanding rib. This all led to the unit thickness of the seats being increased slightly to enable this interlock detail to be formed. Another consequence was that the junction of the precast planks or panels resting on the steelwork was no longer located at the same junction at the valley between the seats and the steps. Indeed, the main support being beneath the valley intersection was not positioned beneath the plank valley.
14. The Contractor submitted a Technical Query (TQ 1117) dated 22 October 2008 to the Architect which called for "an architectural design defining the exact geometry of the step units, including identification of differently shaped units and their location on the stairs". There does not appear to have been any response, at least in writing or in any other evidence, from AEW. For a considerable period of time in 2008 and going into 2009, AEW on at least one drawing C 5005/C simply noted that the valley junction was "in abeyance".
15. By about October 2008 the steelwork under the steps and seats together with the precast planks had been broadly completed. AEW produced further drawings C8420 and C8421A which were ultimately issued for construction in August 2009 which did not show or reflect the steelwork and plank arrangements which had been altered. Similarly, AEW's Drawing C8423, which showed cross-sectional details across the valley, incorrectly showed the position and the relationship between the step and seat valley intersection and the underlying steel and planks, did not show the altered steelwork, which had by then been instructed and wrongly directed the use of standard unit types at the valley intersection rather than specially shaped units which would in fact have been needed to secure an effective intersection between the steps and the seats.
16. The Contractor had retained a specialist sub-contractor, Rowecast Ltd ("Rowecast") to manufacture and provide the precast concrete steps and seats. By early October 2009, the Contractor was concerned that there might be very real problems. The Contractor raised a Technical Query TQ 1676 on 8 October 2009, which compared an engineer's steelwork drawing and AEW's Drawing C8422 saying that "the steel carrying the precast planks and big steps on amphitheatre stairs is out of line by approx. 20 mm in mentioned drawings. This means that the big steps won't tie in with the small steps and the FFL". It recommended a possible solution. It was appreciated that without some significant alterations to the architectural designs there would be an ineffective junction which will also be very unsightly. It seems that as between the Contractor and the Architect one solution was considered promptly. It led to the Contractor e-mailing Rowecast with a sketch of a substantial plinth or upstand section which would cover the junction between the steps and the seat; it would be several feet wide and high and the sectional shape was like a goalpost whose legs would rest on adjacent units; a handrail would be cast into the plinth. AEW considered that the problem was otherwise "fairly insurmountable"; as Mr Rogers said in an internal e-mail on 9 October 2009 saying that there would have to be "a major reconstruct around the valley and the roots of the upper steps" pointing out that the "soffit of the steps is lower than the soffit of the small steps".
17. Throughout the period of October through to December 2009 the waterproof membrane had been laid but it was subject to a very substantial amount of water penetration, which had caused serious leaking into the storage and other areas below where the steps and seats were located. There were scores of punctures and gashes which penetrated all the way through the membrane. This was largely because it had become damaged in numerous places as a result of all the construction activities which were going on around and on the areas in question. Over these months they were gradually repaired and tested for watertightness.
18. On 3 November 2009 the Contractor issued its monthly progress report for October 2009, saying in respect of the amphitheatre area:

"The valley upstands have proved too difficult to design and [accordingly] it has now been agreed with the architect to cast the valley upstands in situ, and then clad this with Jura stone following the installation of the adjacent step units. This enables the geometry to be defined on site now, so that while the valley upstands are cast then the step units can be prefabricated."

19. It is clear, and indeed it is now in effect accepted by AEW, that the Museum was not properly, effectively or at all informed of these problems let alone of the solution being considered by AEW and apparently agreed with the Contractor. AEW confirmed its oral instruction to the Contractor requiring a new layout of seats and steps on 10 November 2009 (CVI 336). On 13 November 2009 it confirmed its instruction (by CVI 340) to the Contractor to introduce the upstand plinth as per attached sketches. This would in any event have required planning permission but it is absolutely clear that the senior echelons of the Museum would never have approved it. In any event, over the next few weeks the Contractor arranged for the plinth to be constructed in effect covering up the wayward and unsuccessful jointing arrangements between the steps and the seats. It involved shuttering. Ms Granville (who is not a building professional person) saw the shuttering but she believed that it was something to do with dealing with the leaking problems.
20. The documentation reveals that the Contractor was working towards completing by the end of 2010. Indeed considerable efforts were deployed by the Contractor in December 2010 to achieve this.
21. In early January 2010 there was very severe weather with snow and once this had cleared Ms Granville was for the first time able to see the plinth arrangement at the valley and between the steps and seats. She described in evidence "shock" because it had always been the clear design intent of the Museum that these concrete steps and seats leading up to the entrance terraces at each end of the Museum would seamlessly flow in a continuous plane so that the tread of every second step unit would flow into the upper surface of the seat units. She called for a meeting with Mr Hiscocks of AEW. She wrote her own notes and asked in simple terms what the plinths were and who approved it. She asked why this had not gone through the change control procedure and Mr Hiscocks said that he did not know. She asked about planning consent and how did AEW "think this could get through" and would no one notice it. Her shock and upset come through her notes and indeed her evidence. She said that it was "wholly unacceptable and "an abomination". Mr Hiscocks was embarrassed and said that he had taken "his eye off the ball". Another important issue was raised which related to substantial gaps between the concrete units, there being particular concern that they were wide enough for high heels to be caught. It was said that this was a risk. Mr Hiscock's notes which were disclosed extremely late by AEW very much coincide with Ms Granville's note. He records that she referred to "this abomination" and that she asked what explanation he had, that it was totally unacceptable and that it had not been passed by the Museum. He records her saying that the plinth had to be removed and substituted by an acceptable alternative; this would not be at the Museum's cost. He records that she asked "if I were satisfied with the detail" and his note is: "I said I was not". His note set out his explanation as to "how it emerged from the need to overcome a geometric problem" and that the plinth as constructed was "far larger than designed".
22. The following day Mr Hiscocks produced a report which stated that the "steps, terraced areas and ramps have significant workmanship, manufacturing, health and safety and design issues". His report addresses six issues:

"1 Manufacturing tolerances

The pre-cast units vary sufficiently in size to allow cumulative errors to occur and create different gaps between units. There are also tolerances in level to allow the trip hazards where they are marginally out of being truly flat. There are variations in the top and bottom line of step units, which gives varied gaps.

2 Workmanship issues

The precast units had been installed with significant variation in care and attention to detail. Some units have spaces between units and others do not. Some units sit exactly square and others do not. Units are tight against the 'wing wall' but then have large gaps across the width of the staircase…

3 Health and Safety issues

There are Health and Safety issues with the valley 'blocks' that over sail the landings, these protrude into the walkway and are dangerous. There are trip hazards with the intersection of the ramps and the terraced areas.

That heel trap issues with the upper steps cannot be overstated as a fall from the top of the flight of steps due to a high heel being trapped will be serious. The gaps are excessive.

4 Health and Safety issues with abuse of valley stones

The sloping top stone on the valley creates on its own a serious Health and Safety issue for children as it is an open invitation to use it as a slide. This is not something that can be redressed by including anti-skating metal strips.

5. Design issues with Valley Steps

The 'as built' valley varies from the original planning approved drawings. This will need a revised planning application as it is a significant variation from the approved drawings…

Conclusion

The whole terrace, ramp, step and amphitheatre seating area has widespread faults in design, manufacture, workmanship and installation. The cumulative effect of these is to make the whole area unacceptable; it will need significant remedial works to address all the above issues."

23. From this moment on, it is clear that a substantial amount of time, energy and resource was applied by the Museum to seek ways to see what could be done and possibly to live with the problem. AEW was asked to come up with appropriate solutions but, although reasonably polite, never did, although various suggestions were made. What did happen however over the next 3 to 4 months was that the "abomination", namely the plinth, was removed and later a number of the steps and seats in the vicinity of the valley were removed. The works in the area were suspended, in effect pending an acceptable resolution from AEW, which never came. Although there was some other work, not connected with the external steps, seats and terraces, which was done up to the autumn of 2010, the primary reason why the works overall were not completed was the problem with the steps and seats, which ultimately was never put right. This was confirmed in evidence by Mr Bettridge, the Contractor's Project Quantity Surveyor, who accepted that the problems associated with the geometry of the steps, terraces and seats became critical as from January 2010 until eventual practical completion in July 2011. In time the area was hoarded and access was generally barred to the public. In February 2010 partial possession of the main parts of the new Museum Building was granted and exhibition fit out works proceeded.
24. The Contractor's standpoint was that it was not responsible for the gaps between the concrete units because it had been working to a 10 mm tolerance or gap and bar a relatively few instances, as it argued, it had complied with that. Internally at least, AEW was expressing the view that the problem with the steps and seats was all the Contractor's or its specialist subcontractor's fault and its involvement was limited simply to giving "design advice… to overcome a construction problem that precluded the steps being built as originally designed" (see "an overview 23. 02. 10").
25. The Contractor came up with some suggestions as to how to overcome at least some of the problems, for instance on 28 April 2010 producing its own "Overview of Amphitheatre Steps, Terraces, Landings and Valley", which suggested using a hard mastic joint to address the gaps or the incorporation of a metal drain grate and the removal of the valley detail in the incorporation of a more discreet valley arrangements to overcome the clash within the superstructure below." The Museum was reluctant to go down the route of using mastic to fill in the joints because that would produce unsightly and uneven lines up and down the building which was not acceptable aesthetically.
26. On 27 August 2010, AEW referred to the considerable dialogue that there had been relating to the steps and amphitheatre seating saying that they sincerely wanted "to assist in a positive way to produce a satisfactory outcome to the current situation". It recognise that the "two basic design options on the table create issues of either poor appearance or difficult construction", these two options being "returning to the original proposal, which creates serious issues of clashes with substructure, or there is an alternative design with a plinth at the intersection of the steps and seats, which is considered ugly." It came up with alternatives, none of which have been pursued as viable in this litigation.
27. Meanwhile claims and counter-claims were passing between the Museum and the Contractor and in December 2010 the Contractor referred to adjudication disputes relating to the responsibility for the problems associated with the precast concrete steps and seats. The adjudicator decided instead in February 2011 that the steps and seating did not form part of the Contractor's "Designed Portion" and that it had been "entitled to instructions in respect of the steps/seating and valley detail, to enable them to carry out and complete the Works, and overcome the discrepancies that exist among the Contract Documents". It is clear that this dispute had come about at least in part by reason of AEW's unwillingness to accept responsibility for what had gone wrong. Indeed in the run-up to the adjudication, AEW wrote to the Museum's solicitors saying that the steps and the seats to the amphitheatre areas "were in fact Contractor Designed" and that the Contractor had "been responsible for the detail, sectional profile, unit link and physical arrangement of this area".
28. The SAS and Armstrong ceilings had been completed before the end of 2009. On 25 May 2011 a large number of SAS ceiling panels in the ceiling of the gallery known as "Creative City" in the Museum fell down and it seems likely that a workman underneath was injured. At this time, the Museum was planning to open the Museum on 19 July 2011, notwithstanding the problem with the steps and seats. On being told, Ms Granville went immediately to the Museum and she saw that a substantial percentage of the ceiling had fallen in the other areas, with panels hanging down and in danger of further collapse. I accept her evidence on this. The Museum decided, wholly reasonably, that all of these ceiling panels had to be removed from where they were, and temporary measures had to be put in place to make the electrical installation and fittings robust and safe. Debris had to be cleared and there were remedial works to damaged exhibitions and areas. A very substantial amount of overtime had to be worked and, given their budget restraints, a substantial reduction had to be made in the exhibitions and exhibits which could be put on display.
29. In effect, the outstanding work in relation to the seats and steps had to be omitted from the construction contract and practical completion was certified in July 2011 to enable the public opening to take place, albeit on a somewhat restricted basis.
30. Following the opening, and after a period of high winds, museum staff noticed that Armstrong ceilings tiles had become dislodged in January 2012 and indeed had fallen from the lobby areas to the main entrance doors. Unsurprisingly, Ms Granville describes this as alarming, particularly in circumstances in which on one occasion a visitor was hit by a tile as it fell suffering a blow to her shoulder. Again on 4 April 2012 a large section of the ceiling within the main entrance lobby collapsed. Again, temporary measures have had to be taken to make these ceiling areas safe.
31. I accept Ms Granville's evidence, which was not challenged, that the reason that the Museum has not been able to do the extensive remedial works required has been lack of funds.

The Witnesses

32. No factual witnesses were called by AEW and there is no evidence before the court as to why it called no such evidence. Two witness statements had been exchanged but their statements were withdrawn during the trial and I have therefore paid no attention to their contents. There is therefore little or no evidence from the actual architects involved seeking to excuse or explain at least why they did what they did or failed to do.
33. Witnesses actually called by the Museum were as follows, with my comments on their reliability:

(a) Sharon Granville: the Executive Director of the Museum who had been seconded into the project on a full-time basis since 2004, spent a considerable amount of time setting up the project and keeping a reasonably close eye on what was going on. She was astute and experienced in her job. For instance her descriptions relating to the actual and potential disruption to the work and exhibits of the Museum during the remedial works were extremely helpful in giving a very real insight into the major difficulties which the Museum suffered and will suffer when the remedial works were and will be carried out; that had the ring of absolute truth about it. She became even more involved when it began to emerge that there were problems with the steps and seats. She was a very impressive witness and one whose evidence I have no difficulty in accepting largely in its entirety. She was prepared to make concessions with regard to some of the quantum evidence which underlined her basic honesty and integrity. She was subjected to polite but firm cross-examination by Leading Counsel for AEW about quantum matters but she stood up extremely well to that and I found her immensely believable.

(b) Colin Matley: he was from August 2005 the Quantity Surveyor for the project employed by Turner and Townsend. He was originally called to give evidence primarily in relation to an issue raised on the pleadings by AEW, which was the extent to which the Client Change Control Procedure had been implemented, in particular in relation to CVI 340 and the construction of the plinth in late 2009. He explained that he had produced some of the details of quantum and indeed it was primarily about that area of the case about which he was cross-examined. I found him to be a decent and convincing witness.

(c) John Hewitt: he was from November 2008 the Contract Administrator who had 26 years' management experience on large-scale construction projects in the UK and abroad. Again his evidence was called to deal with the Change Control Procedure. Although initially somewhat nervous when he started to give evidence, he gained confidence as a witness. I formed the view that he had a good general recollection of what had happened, that he was a decent and positive witness and that he was broadly a credible witness. In particular his evidence about the leaks through the membrane in the steps and seats areas was clear and firm.

(d) Ian Williams: he has worked for the Museum for some 13 years and had been involved in the Museum project since its inception. He was the Director of Estate Management with responsibility not only for the Museum but also a number of other museums and galleries run by the Claimant. He was a straightforward witness and ready to concede that an estimate of time spent by him in relation to the steps and seats works might be excessive. He was involved in the steps and seats problems as they emerged in early 2010 and again with the ceiling collapses and problems. He was asked questions that went to quantum and I found him to be impressive and believable.

(e) Martin Hemmings: he has been the Building Operations Manager within the Estate Management Department of the Museum since about 2002 and was resident on-site that this project from June 2008. He was the "eyes and ears on site" for the Museum. He was down-to-earth, sensible and honest. Again, he was asked questions which related to quantum and what he had to say was believable. He gave some practical evidence about how very complicated the process of lifting and placing the seats and seats actually had been. He gave practical and helpful evidence about likely access problems when remedial works are to be done

(f) Robert Batchelor: he was the Client Project Manager for Exhibition Projects Ltd which was retained by the Museum in connection with the exhibition fit out of the Museum. He gave evidence in connection with aspects of quantum in relation in particular to the work required to the SAS ceilings areas and in relation to other work yet to be done. He was sensible and a decent straightforward witness.

(g) Martin Lawton: he was the Project Manager for the new Museum project taking over that role in July 2009. He was employed by Mace Ltd which was in turn employed by the Museum he was called to give evidence about liability and was mostly cross-examined about quantum and in particular about his and his firm's involvement in the aftermath of the steps and seats issues arising. He was a reliable witness.

34. The Contractor presented two witnesses for cross-examination:

(a) Peter Bettridge: he was the Project Quantity Survey who was effectively the site representative for the Contractor. Although honest, I felt that he was somewhat careworn if not diffident in the giving of his evidence. He did not always answer relatively simple questions put to him. Much of his written evidence was not challenged but I am circumspect about the reliability of his evidence where it differs from contemporaneous documents.

(b) Torben Seemann: he was an engineer assigned to the Museum project in April 2009 primarily to monitor and promote quality assurance. Much of his evidence was related to the chronology and correspondence. He was a reasonably reliable witness.

35. In addition to the witnesses presented for cross-examination, there were statements of witnesses who were not required to attend for cross-examination, whose evidence I have considered and have regard to where relevant.
36. I now turn to consider the experts' evidence. The Museum's architect expert was Mr Roger Jowett who is an extremely experienced architect and indeed expert. He produced by far the best expert report of all the architect experts. When giving evidence he came over as extremely thoughtful, serious and knowledgeable. He was able to explain himself in language non-architects could understand. He had carefully analysed all the issues and gave the most comprehensive and credible evidence about not only the technicalities but also responsibility and the need or desirability for remedial works.
37. In contrast, Mr Richard Pepper, the architect expert called by AEW was, although honest, almost wholly unimpressive, possibly partly because he had never given expert evidence before. He had the advantage of being called simultaneously with Mr Wasilewski, AEW's engineering expert but, in spite of the encouragement, if not prompting, provided by Mr Wasilewski sitting beside him, it was clear that he had given little or no coherent thought to the issues in the case. I was surprised (to say the least) to be told by Mr Wasilewski that he and Mr Pepper (who both work for the same firm) had not been asked to consider what could reasonably be expected of architects in AEW's position. This extraordinary state of affairs (in a case all about alleged professional negligence on the part of architects) may explain why such little coherent thought had been given by Mr Pepper to this aspect of the case. Mr Pepper was wholly unconvincing about all aspects of liability. He made a concession under cross-examination which one would simply never expect a competent expert who was aware of his duties to the court to make; he accepted that he was "seeking to defend the indefensible for the benefit of AEW" (Day 7 Transcript Day lines 12 to 16). He was faltering in his evidence and often did not seem to understand the questions (which were never unclear or over-sophisticated). I can place no weight on any of his evidence, save where another expert may have agreed.
38. Mr Alexander Fleming was the architect expert called by the Contractor. He was reasonably experienced, albeit not as experienced as Mr Jowett. He was a decent expert who gave his evidence in a positive way. His evidence was primarily limited to the steps, seats and terraces issues. However, he also changed his position at a relatively late stage to agree with a number of remedial steps which were likely to be required, which hitherto he had disavowed or not positively supported.
39. I have no doubt in preferring the expert evidence of Mr Jowett certainly over Mr Pepper and, save where he was in agreement with Mr Jowett, Mr Fleming. It was a matter of some interest that the defending parties' experts moved a not insignificant way towards Mr Jowett's views on the scope of remedial work as the trial moved forward. That tends to confirm that he was the more reliable and, at bottom, the most reliable expert in the case.
40. Moving on to the engineer experts, Mr Neil Tutt for the Museum was the most experienced engineer and expert of the three who were called. He was absolutely straightforward in the giving of his evidence and he was authoritative. I was very impressed with him as I formed the strong view that he was the most pragmatic of the three engineer experts.
41. Mr John Wasilewski was also experienced having worked as a consulting engineer for 35 years after nine years working for a contractor. He is an experienced expert. I felt that he was often argumentative if not combative (albeit polite) when cross-examined. It was clear that he was too willing and too quick to try to explain away or qualify answers given by Mr Pepper, sitting beside him; it was almost as if he was trying to protect his fellow employee when Mr Pepper apparently made concessions against AEW's interests. I wrote down in my notebook towards the end of his evidence that he had adopted a "firefighting" approach to seek to circumvent or soften what Mr Pepper had said. Certainly I would not describe him as partisan but this behaviour in the witness box inevitably has coloured my views about his reliability in this case. He was unimpressive in his views about quantum issues and some aspects of the remedial works and was obliged as the trial went on, even up to the 11th hour of the conclusion of the evidence, to concede that a number of the remedial steps put forward by Mr Jowett were right. An example of this was the belated acceptance by him on Day 7 of the trial that all of the remaining steps and seats left in place would have to be removed to be inspected and possibly replaced. He appeared to be unsure of himself in relation to some aspects concerning the liability of AEW in relation to the geometry of the steps, seats and terraces. I formed the view that he tended to oversimplify what had proved historically to all concerned to be intractable and almost insoluble problems with the geometry of the steps and seats.
42. Dr John Roberts was the engineer expert called by the Contractor and, although sufficiently experienced, he was the least experienced of the three. He is however eminent, having served for instance as President of the Institution of Structural Engineers. He was decent and straightforward although he was chatty and occasionally somewhat argumentative. I felt that his approach to the practicalities involved with the design was somewhat academic, for instance when he suggested that it would be feasible to use heaters to keep the steps free of ice or using propylene glycol (used on airport runways and very expensive) to do the same job. He also accepted belatedly that some of the remedial steps called for by Mr Jowett were necessary which tended to undermine his reliability on this aspect of the case.
43. Of all three engineering experts, I found the most sensible and reliable expert to be Mr Tutt.
44. Moving on to the quantity surveyor experts, Mr Neil Fitch was called by the Museum, Mr Robert Matthews by AEW and Mr Mervyn Raybould. Mr Fitch is an experienced quantity surveyor with the well-known firm of EC Harris. Mr Matthews has similar experience as a quantity surveyor and has worked for BPP Construction Consultant for about 20 years. Mr Raybould works for Ridge & Partners and is a chartered quantity surveyor. Mr Fitch came over as being highly experienced, decent, straightforward, independent and pragmatic; he had looked at the Museum's quantum critically and for instance strongly expressed his view that the claim for project and cost management and contract administration was pitched much too high. Mr Matthews came over as sensible and decent albeit politely combative. I felt however that he was too often proceeding on the basis of supporting the minimum cost of future work that could be justified as opposed to the reasonable or probable cost. In relation to past costs, he was, probably unwittingly, unhelpful in that when he could not find appropriate invoices and receipts then he would simply allow nothing; an example is an item in relation to the work done on the SAS ceilings in which £48,675.25 was claimed in relation to "accelerated working" in respect of which Mr Matthews allowed £20,166.25, a difference of some £28,509. He essentially said that he had seen no invoices to support the balance. However it is clear that there was supporting documentation in relation to this part of the claim. Mr Raybould also came over as decent but I felt that like Mr Matthews he was too often seeking to put forward the minimum as opposed to the reasonable or probable cost of items. I felt that he saw the various remedial works as extremely simple and not involving the need for any real measures to allow for actual or foreseeable difficulties. Overall, whilst all the quantum experts made helpful contributions, I broadly preferred Mr Fitch.

Liability (Architect)

45. I intend to take this aspect of the case fairly shortly primarily because I found Mr Jowett very convincing and indeed he was supported in a number of his views by Mr Fleming and because I found Mr Pepper conversely unimpressive. Towards the end of the evidence (Day 8), it must have been clear to those advising AEW that it was likely that Mr Pepper may have "given the game away" on liability and I enquired of Mr Reed QC whether liability remained in issue. He told me that he would take instructions but that he had to live within his instructions. Apart from the admissions which had been made in his opening, no other admissions of liability have been made, although Mr Reed QC did not spend much time in his closing on many aspects of liability.
46. The following was admitted by Counsel for AEW in Appendix 1 to their written opening (mostly by reference to the pleadings) and following traversals in the Defence:

(a) AEW was responsible for the general layout of the geometry of the steps and seats.

(b) The Contractor's Technical Query, TQ 1676, identified what it believed was a "clash".

(c) Following discussions on site, it was AEW which proposed the "plinth" solution in CVI 340.

(d) (Although this had not been alleged as such by the Museum), AEW's original design was capable of being constructed by the Contractor and therefore it should have informed the Contractor that this was so in answer to TQ 1676. Accordingly, CVI 340 should not have been issued. It was accepted orally by Mr Reed QC on behalf of AEW that this was negligent of AEW.

(e) The Museum is not bound by any agreement in relation to be construction of the plinth and did not acquiesce in its construction.

(f) The SAS ceiling was not designed adequately by AEW in that the original specification in September 2006 specified that the lighting tracks and the ceilings within the museum were to be supported separately and AEW amended that design so that the ceilings were to be installed supportive by ERCO lighting track; the design should have been as per the original specification. Other aspects of the design set out in Paragraph 39 of the Particulars of Claim were accepted as being inappropriate. Mr Reed QC also confirmed orally that in this context AEW was negligent.

(g) It was accepted that the design was not adequate in relation to the Armstrong Ceilings in that additional perimeter clips were required to be installed. However this was a matter for the specialist subcontractor. Mr Reed QC did not accept that there was any liability in this context.

47. Relevant parts of AEW's Deed of Appointment are as follows:

"3.1 The consultant shall provide those services included in Schedule 1 Part 2…

3.5.1 [AEW] warrants and undertakes to the Employer that he shall perform his duties such that the Project will comply with all planning…permissions and conditions…

3.5.3 [AEW] further warrants and undertakes to the Employer that in respect of the complete architectural services in relation to the Project as set out in this Deed he has exercised and will continue to exercise reasonable skill and care and diligence to be expected of a professional person acting in the capacity of a consultant experienced in carrying out such services for a development comparable in size, scope, complexity and purpose to the Project and within the scope of this Deed.

3.5.4 [AEW] further warrants and undertakes to the Employer that in respect of the Services he has carried out pursuant to the Sub-Appointment [when engaged by 3XN] he has exercised the reasonable skill and care and diligence which may reasonably be expected of a properly qualified and competent Architect/Contract Administrator experienced in carrying out such services as those specified in the Sub-Appointment."

48. Schedule 1 Part 2 listed the Services to be provided by AEW:

"A. The General Scope of Services

1.2.1 Design and document all architectural elements including advising on quality control during contract.

1.2.2 Lead the design team and coordinate the work of design team members including:

Acting as central point of contact for the design team

Overall coordination of the design…

Visit Site to prepare snagging lists prior to Practical Completion

6.1 The Consultant shall:-

… 6.1.2 As Design Team Leader the Consultant will liaise with the M&E, Structural, or consultants as well as other specialist subcontractors and consultants to ensure all elements of the Project are fully co-ordinated...

8.1 Ensure that proper and sufficient information, drawings, details, instructions, notices and the like are provided or given to the Contractor and Work/Sub-Contractors by the Professional Team in due time and in accordance with the Information Release Schedule and the Project Programme.

8.2 Ensure that the members of the Professional Team provide adequate supervision and regular site inspections in accordance with their terms of appointment, including the provision of resident site staff.

8.3 Ensure that the members of the Professional Team discharge their contractual responsibilities in respect of completion, defects and remedial works.

11.1 The Consultant shall:-

11.1.1 Provide such input, information, advice and assistance as necessary to enable each consultant's design leader in the Professional Team and the Museum Exhibition Designers to fulfil their duties and responsibilities and to ensure there is the interface between each design discipline.

12.1 The Consultant shall:-

12.1.3 Visit the site on a regular basis to inspect the progress and quality of the Works and to determine that they are being executed in accordance with the contract documents.

12.1.4 Direct and control the activities of the site staff

B. The Specific Scope of Services – Architect

6.1 Develop a co-ordinated detailed design from the approved scheme design in accordance with the project brief and cost estimate…

6.5 Prepare production information comprising the following:

… 6.5.2 fully detailed and coordinated dimensioned floor and reflected ceiling fans, sections and elevations showing all internal and external arrangements.

6.11 Participate in preparation of project wide definition of tolerances covering architectural elements and related interfaces.

11.1 Provide further production information as required in accordance with the programme of works and/or agreed information release schedules

11.2 Receive design, fabrication and installation drawings from contractors and check for adequacy, accuracy and adherence to the design concept and authorise for construction where applicable.

C. The Specific Scope of Services - Design Team Leader

At All Stages

5.10 Receive material from other participants and prepare a project wide definition of tolerances

6.4 Coordinate the preparation/checking as appropriate of operation and maintenance manuals prior to handover of each stage of the Project."

49. It will be seen from the above list of services that the co-ordination role undertaken by AEW was an important one and that there had to be a clear ("project wide") definition of tolerances. It is abundantly clear from the evidence that AEW was extremely poor at the co-ordination function (at least in regards to the issues with which this case is concerned), although it is at least possible that the individual architects involved misunderstood what roles AEW had contractually undertaken. Correspondence reveals that it had little or no grasp on what was going on in relation to the different elements which made up the steps, seats and terraces and their relationship with the underlying structure of steelwork and concrete planks. AEW never drew up any project wide definition of tolerances. Indeed, it is unlikely that it applied its corporate mind at all to the need for such a definition in relation to the steps, seats and terraces. For instance, AEW did not itself specify any particular gaps between the steps, seats and terraces and did not obviously or at all even delegate that responsibility to anyone else; all that it did was to leave it to Rowcast to specify some gap between the units and even then did not apply its mind either to whether the gap was an appropriate one anddid not consider how by the application of normal construction and manufacturing tolerances that gap might in practice be exceeded. The documentary evidence, much of which I have not set out above, suggests very strongly that AEW regarded the Contractor and Rowcast (in relation to the steps, seats and terraces) to have the full design responsibility with Buro Happold having the checking function in relation to detail design or fabrication drawings. This was simply wrong as the steps, seats and terraces were architectural features, albeit comprising mostly pre-cast concrete units. As Mr Jowett says at Paragraph 3.1.1 of his report, these steps and terraces formed "significant architectural features at the Northern and Southern frontages of the building and were a key visual element of the initial design" and involved the integration of "a series of flights of steps with a series of banks of concrete seating in a visually striking combination".
50. It is also equally clear that the relevant architects within AEW who were involved simply had no or no real understanding about the geometry for the steps, seats and terraces. That is apparent from the overall evidence, including the expert evidence of Mr Jowett, contemporaneous documentation and indeed from the admissions above. The truth is that AEW knew and must have known by the October or November 2009 period that there had been a serious mistake and that it was simply not possible to achieve the practical and aesthetic effect required by the client and indeed by the planning permission which had been obtained. It is simply extraordinary that competent architects could consider that it was acceptable to adopt the plinth solution in any event given their client's aspirations and wishes and, even worse, without seeking the informed approval of its client. It was committing its client not only to expenditure involved in this change but also to a solution which it must have realised was unlikely to be acceptable. Mr Hiscocks himself said to Ms Granville in January 2010 that he was not satisfied with the detail and that he had "taken his eye off the ball". He clearly did not even understand from the sketches and plans provided for the plinth how big it was going to be. This is symptomatic of architects who simply had no real idea what they were instructing. This sequence of events in the last three months of 2009 has all the hallmarks of architects who realised that something serious was wrong and thought that they could get away with physically covering it up with the plinth arrangement.
51. It is also noteworthy that AEW were unable to come up with any sensible solution to the geometry problem after the unacceptable situation had been exposed. It was only well after proceedings were started and probably after the involvement of experts that AEW or their insurers have come up with a remedial scheme which is said to be satisfactory and simply reflects what may or should have been instructed by AEW in the autumn of 2009. Again this is symptomatic of architects who simply had no idea why there was a problem.
52. I therefore turn to the allegations relating to the steps, seats and terraces. I start with the Amended Particulars of Claim. Paragraph 7.1 refers to the Steps and Seats and terrace areas collectively as "Steps and Terraces" (Paragraph 7.1). Paragraphs 15 to 18 describe how AEW redesigned the Steps and Terraces as shown on their drawings C8420 to C8423, one effect of which was that the step and seat units sat directly on the membrane on the structure rather than being supported in a metal sub-frame and one consequence of which was that based on C8423 (detail 9), the junction between the upper surface of the seat and the step occurred at a different position to that shown on the plan drawings. Paragraph 16 refers to the redesign as requiring each step/seat unit to interlock with one another in order to provide sliding restraint. Paragraph 17 asserts that the effect of the redesign was that no one step or seat unit could be removed in isolation, that unless some means of introducing dimensional tolerance was made, it would not be practical to achieve the position needed for the alignment of the step/seat units and that it produced a lack of coordination between the geometrical relationships between the pre-cast seat and step units and the junctions in the underlying structure as well as inadequate provision in the design for the accommodation of construction tolerances necessary to achieve the appropriate precision of assembly. Paragraph 18 goes on to say that the clash between the planks laid across steel beams and the installation of step/seat units was not corrected by AEW; because each sloping plain (the seats and the steps) were at differing angles of pitch, there was no room for error or tolerance in setting out the angles of pitch and the precise location of intersection. Paragraph 18.2 asserted that the design was "simply unfeasible in any practical sense and that it was entirely possible or probable that even a competent contractor would be unable to properly fit the steps and seats without an appropriate allowance for tolerance incorporated into the design".
53. Complaint is made that CVI 340 was issued without approval from the Museum and that the plinth solution did not have planning permission and was inappropriate and unacceptable in terms of safety, utility and aesthetics (Paragraph 22). In addition to the geometry problems, Paragraph 24 complains that the specified cover for the reinforcement within the precast seat and step units at 25 mm was insufficient and that even the specified cover was not achieved and so it is asserted that the units were fabricated with insufficient cover; this is of some importance because, if inadequate cover is provided, there will likely be an inadequate life or durability. Furthermore, Paragraphs 26 and 27 complain in terms that the steps and seats had excessive gaps between them, the complaint being in effect that AEW caused, allowed or permitted an excessive gap (10 mm being shown on various drawings and with most gaps actually on site being in the range of 10 to 20 mm wide). This is said to be dangerous because it can be a finger or heel trap. A further complaint is made relating to the utilisation of a single layout of waterproofing membrane, which it was argued was a negligent specification. However this argument is no longer pursued as an allegation of negligence.
54. So far as the complaints relating to the geometry are concerned, I broadly accept the evidence of Mr Jowett in this regard. In essence, AEW fell below the standard to be expected of a competent architect because they failed from start to finish to appreciate or understand the basic geometry, particularly in and around the valley area. It failed in its design to understand or illustrate the central feature of the junction between the step and seat units which was that in order for the treads of alternate steps to align with the tops of the seat units, the seat units would project across the valley and that those units in order to avoid running into the plane of the structure beneath the steps, needed to be shaped with appropriate chamfers or bevels on the underside. What it did do was to produce on several drawings six different types of seats and steps but none of these made any or any comprehensible provision for what was supposed to happen at the valley junction. Additionally it failed to appreciate and make appropriate design allowances for the fact that the junction between the steps and the seats was offset from the underlying supporting planks and that appropriate additional supports in terms of ribs needed to be provided. It was, additionally, negligent of AEW and a breach of its contract in October and November 2009 to instruct the Contractor to embark upon the plinth solution. It was a breach of contract amongst other things because AEW did not have permission to issue this instruction and also because it would have taken little on its part to appreciate that it was and would have been sensible to secure its client's agreement to something which would produce a very different aesthetic effect than had been presaged in all the earlier designs and in the planning permission secured for the Museum. The history of the plinth is also the strongest evidence that AEW itself at that stage, probably before and certainly afterwards, never really understood the geometry of and correlation of the steps and seats, yet it was instructing changes which simply hid the architecturally botched job at the junction.
55. So far as gaps are concerned, AEW was negligent simply and broadly because it never applied its mind to what an appropriate gap should be. It is clear that at an early stage AEW appears to have identified a possible gap of 8 mm between units but when the design was changed by 2009, there was no specified no dimension between the units. Rowecast did produce drawings which showed a gap of 10 mm between abutting units along runs of seating or steps albeit no gap at the rear of the seating or steps and it appears that such drawings were approved, albeit it seems improbable that AEW ever applied its mind to this aspect of the drawings produced by Rowecast. It never produced or secured the production of a tolerance specification as its contract expressly required it to do and in any event it never actually specified what tolerances would apply both in the manufacture of the precast steps and seats or in their installation. Since it did not specify any gap and because it did not specify tolerances, it was entirely predictable that gaps between the units would vary.
56. Similar considerations apply in relation to the terrace slabs, over which people could be expected to walk and pass. There was no specification in relation to the gaps between the terrace slabs and no consideration seems to have been given by AEW to this either. The bulk of the gaps were 10 mm or more and there can be little doubt that AEW was negligent in causing, allowing or permitting this state of affairs.
57. There was nothing wrong in there being a gap between the units but it was important aesthetically and from a health and safety standpoint that there was a small specified gap and certainly one less than 10 mm. Aesthetically, it was important because the gaps create visual lines and if at one point on a given line the gap is 1 mm and the next unit is 15 mm wide that can be very obvious and therefore the aesthetic symmetry is visually undermined. From the health and safety standpoint, many (mostly) women wear shoes with heels, some of which are narrow. Blind people have often narrow canes to assist them as they walk. I accept the evidence of Mr Jowett that gaps of no more than 5 mm width at the most and with limited tolerance were required here. There was a lot of evidence about whether the Building Regulations were applicable in relation to determining what the appropriate width of gaps should be but it is unnecessary for me to resolve that issue because I am satisfied that all competent architects exercising reasonable care and skill should have specified gaps of no more than 5 mm. In that context, AEW was negligent.
58. I now turn to the issue relating to reinforced concrete cover. In summary, in my judgment, a carefully co-ordinated design for the seats and steps should have called for a minimum of 30 mm and probably 35mm of cover rather than the 25 mm cover in effect approved by AEW and Buro Happold and used by Rowecast in the manufacture of the steps and seats. A major failing either of design or of coordination or both on the part of AEW was that no particular specification requirements as to cover were produced at all by the design team in relation to the steps and seats. This was an extraordinary lapse on the part of AEW even if it mistakenly thought that it and the design team had no responsibility for the detail design of these units. There is a suggestion made in 2009 and 2010 by AEW and to some extent repeated in this litigation that the Contractor was in some way exclusively responsible for the design of these units. That is not correct. However, the building contract between the Museum and the Contractor identifies that the Contractor was to have design responsibility for (so far as is material to this issue) "reinforcement placement and scheduling"; even this design responsibility involved at most "completing" the design (as referred to in Clause 2.1.2 of the construction contract). It would be necessary for the Architect to draw up or to ensure that there was drawn up a general specification which identified the criteria upon which the design for the reinforcement placing and schedule was to be based. Otherwise the Contractor and in this case its sub-contractor would be left to their own devices (albeit required to exercise reasonable care and skill in so doing) and the Architect or other members of the design team whose job it was to vet and approve the Contractor's design offerings would have no criteria against which to check such drawings and/or calculations. Mr Jowett says, and I accept, that there was no adequate definition by AEW or Buro Happold of, in particular, cover to reinforcement for the steps and seats.
59. So far as what the specified or possibly approved reinforcement cover should have been, there was much emphatic debate by the experts engendered by some firm cross-examination. Much of this debate involves considering a variety of British Standards and Codes of Practice, with different parties and experts seeking to support the need or desirability of cover ranging between 20 mm and 35 mm. I start from the proposition, accepted by all and in any event clear on the evidence, that this building was to be a prestigious one and was intended to provide an architectural legacy to the people of Liverpool. Mr Tutt rightly describes it as a "dramatic, landmark structure" which it clearly was intended to be. It was not a temporary building or a concrete tower block intended to be removed and replaced within 25 years or so in any event. It was supposed to have a long life. It is again clear that AEW in the specifications produced for the project did not actually identify specifically what useful life the steps and seats were supposed to have; a document produced by Buro Happold ("Building envelope description and cladding types") defined a design life of the building of 100 years and of the facades of 50 years but, of course, the steps and seats do not as such fall within either of these categories. Although the experts have agreed in effect by analogy that it would be reasonable to interpret the specification as requiring a 50 year design life for the steps and seats, the failure to identify a design life for these aesthetically and functionally important amphitheatres is symptomatic of an architect which had simply not applied its mind to what was required for key elements of the works. However, in the light of what the experts have agreed, necessarily I therefore proceed on the basis that, if AEW had applied its mind to what the design life of the steps and seats should be, it could reasonably have come up with 50 years and it is by reference to that criterion that I go on to consider what cover should have been specified.
60. I asked several of the engineer experts whether in the light of the importance of the building and the design life it would be better to err on the side of caution in fixing the amount of concrete cover for the steps and seats. Mr Tutt convincingly answered that it would not be right to be academic about this and one should err on the side of caution. I accept that evidence as sensible and logical not only because I found him a convincing witness but also because sensible and competent consultants should obviously do so; it is almost a matter of simple common sense that for a prestigious building on a waterfront in a major city, one would want to be extremely confident that these steps and seats would not start cracking or otherwise failing because of some even arguable basis a somewhat lower figure for concrete cover, by some strict or academic application of one or other British Standard, might be said to apply. There has been no suggestion by any of the experts that the deployment of concrete cover of 30 mm or 35 mm would or would necessarily cost any more than cover for 25 mm. There is no cost basis therefore for justifying the lower amount of cover.
61. BS 8500 was a requirement called for by the Specification produced by Buro Happold for in situ concrete. The specification tabulated external concrete cover for concrete cast in situ as 50 mm. Mr Wasilewski's view on this (as agreed in the Joint Statement - Paragraph 1.5.5) was that, although Buro Happold did not specify cover for pre-cast concrete, the standards referred to in the in situ concrete specification are a useful guide to the necessary characteristics and the foreseeable performance of the pre-cast concrete elements. This chimes with common sense, although one must bear in mind that precast concrete is often better prepared, manufactured as it is usually in factory conditions. Buro Happold also produced another specification entitled Building Envelope, Stone Faced Precast Concrete Panels, which, although most of it could not relate to the seats and steps in the amphitheatres, does also refer to stairs and stones used for steps. This specification refers to BS8110 and it might be the case that this was intended to apply to the steps and seats (although even that is not clear).
62. BS 8110 dictates that the amount of concrete cover for reinforcement depends upon the exposure conditions described in BS8500-1 and on the characteristics of the concrete. BS8500-1 identifies five exposure classes of which three are relevant: XD (reinforced concrete subject to contact with water containing chlorides (for instance de-icing salts) other than from seawater), XS (reinforced concrete subject to contact with seawater or air carrying salt originating from seawater) and XF (concrete subject to freeze/store cycles whilst wet). These various classes were as follows (in tabular form), with the right hand box being headed "Informative examples applicable in the United Kingdom":

"Corrosion induced by chlorides other than from seawater (XD classes) (where concrete containing reinforcement…is subject to contact with water containing chlorides, including de-icing salts, from sources other than from seawater)

XD1	Moderate humidity	Concrete surfaces exposed to airborne chlorides… Parts of structures exposed to occasional or slight chlorides condition
XD2	Wet, rarely dry	Reinforced and prestressed concrete surfaces totally immersed in water containing chlorides…
XD3	Cyclic wet and dry	Reinforced and prestressed concrete walls and structure supports… Reinforced pavements car park slabs

Corrosion induced by chlorides from seawater (XS classes). (Where concrete containing reinforcement…is subject to contact with chlorides from seawater or air carrying salt originating from seawater)

XS1	Exposed to airborne salt but not in direct contact with sea water	External reinforced and prestressed concrete surfaces in coastal areas
XS2	Permanently submerged	Reinforced and prestressed concrete surfaces completely submerged and remaining saturated; e.g. concrete below mid-tide level
XS3	Tidal, splash and spray zones	Reinforced and prestressed concrete surfaces in the upper tidal zones and the splash and spray zones [Note E: Exposure XS3 covers a range of conditions. The most extreme conditions are indeed spray zones. The least extreme is in the tidal zone where conditions can be similar to those in XS2. The recommendations given in this annex take into account the most extreme conditions within this class.]

Freeze-thaw attack

Where concrete is exposed to significant attack by freeze-thaw cycles whilst wet)

XF1	Moderate water saturation without de-icing agent	Vertical concrete surfaces such as facades and columns Non-vertical concrete surfaces not highly saturated, and to rain or water
XF2	Moderate water saturation with de-icing agent	Concrete surfaces such as parts of bridges, which would otherwise be classified as XF1, but which are exposed to de-icing salt either directly or as spray or run-off
XF3	High water saturation, without de-icing agent	Horizontal concrete surfaces, such as parts of buildings, where water accumulates and which are exposed to freezing…
XF4	High water saturation, with de-icing agent or seawater	Horizontal concrete surfaces such as roads and pavements, exposed to freezing and to de-icing salt either directly or as spray or run-off Concrete surfaces subjected to frequent splashing with water containing de-icing agent and exposed to freezing

63. Tables A4 and A5 in BS8500 identify covers for reinforcement and concrete mixes against, amongst others, the XD and XS classes assuming an intended working life of at least 50 years. Mr Tutt said that, had proper consideration being given in effect by the consultants, such consideration should have arrived at the following classes for the northern amphitheatre: XD3, between XS1 and XS3 and XF4 and for the southern amphitheatre: XD3, XS1 and XF4. He assumes that de-icing salt would be used on the steps and seats largely because they are open to the public, it rains and snows in Liverpool and the surfaces are therefore prone to ice in winter. That was and is a legitimate assumption because de-icing salts are the most common and by far the cheapest way of de-icing; certain it is that neither AEW nor any other consultant suggested or hinted at any material time that such a common method of de-icing should not be used. If the durability of the concrete was dependent on the Museum not ever using de-icing salts, one would have expected that to have been raised with the Museum and, if that assumption was to be adopted and accepted by the Museum, AEW should have secured that it found its way into one of the construction contract specifications.
64. There was much discussion between the experts in the giving of their evidence whether the two other methods of de-icing could or should reasonably have been anticipated to have been used. The first (which was most strenuously proposed by the defending parties' experts) was the use of propylene glycol which is primarily used to de-ice aeroplanes. I unequivocally reject that this method was feasible or would have been considered or foreseen by any sensible contractor, architect or even engineer as an appropriate way of de-icing steps and seats on a building such as this. It was in effect accepted that it has never been used to de-ice buildings such as this; it would undoubtedly be very much more expensive than the use of ordinary de-icing salt (which is readily available). No quotation and no literature were proffered by the experts to support its use.
65. The second method involved the wholly impractical one of the use of manually operated hot air blowers. Whilst of course the application of hot air to ice will melt the ice, it would need a number of workers to be constantly available for up to 4/5 months a year, particularly in cold or snowy conditions because freezing conditions will re-freeze. Another related suggestion was that the access to the building provided by the north and south amphitheatres should be curtailed during cold weather. However, that would restrict the use of the building and was not the basis on which it was designed. There was some dispute as to the extent to which the amphitheatres formed part of the fire exit arrangements from the other internal parts of the Museum. It is clear however, and I find, as a matter of fact based on all the evidence that they were part of such arrangements.
66. It is not therefore that there are no other theoretical ways of dealing with ice in the amphitheatres but it is the case that there are no practical, sensible and well known ways of dealing with it other than using ordinary de-icing salt. The reality is that neither AEW nor anyone else on the consultants' or the Contractor's side gave any thought at all to this important aspect of design. They should all have done so.
67. The experts have agreed in effect that, if the consultants had thought about the reinforced concrete cover requirements for the seats and steps, they would reasonably have had regard to another British Standard BS EN 13369, entitled, "Common rules for pre-cast products" which in turn directs the reader to BS EN 206-1: 2000 which has similar "exposure classes" to those set out in BS 8500:

"Corrosion induced by chlorides other than from seawater

Where concrete containing reinforcement…is subject to contact with water containing chlorides, including de-icing salts, from sources other than from seawater)

XD1	Moderate humidity	Concrete surfaces exposed to airborne chlorides
XD2	Wet, rarely dry	Swimming pools. Concrete exposed to industrial waters containing chlorides …
XD3	Cyclic wet and dry	Pavements. Car park slabs

Corrosion induced by chlorides from seawater

Where concrete containing reinforcement…is subject to contact with chlorides from seawater or air carrying salt originating from seawater)

XS1	Exposed to airborne salt but not in direct contact with sea water	Structures near to or on the coast
XS2	Permanently submerged	Parts of marine structures
XS3	Tidal, splash and spray zones	Parts of marine structures

Freeze-thaw attack (XS classes) (where concrete is exposed to significant attack from freeze-thaw cycles whilst wet)

XF1	Moderate water saturation without de-icing agent	Vertical concrete surfaces…exposed to rain and freezing
XF2	Moderate water saturation with de-icing agent	Vertical concrete surfaces of road structures exposed to freezing and airborne de-icing agents
XF3	High water saturation without de-icing agent	Concrete surfaces subjected to frequent splashing with water and exposed to freezing Horizontal concrete surfaces exposed to rain and freezing
XF4	High water saturation with de-icing agent or seawater	…Concrete surfaces subjected to direct spray containing de-icing agents and freezing. Splash zones of marine structures exposed to freezing

68. Both BS 8500 and BS EN 13369/ BS EN 206-1: 2000 have slightly different classifications and different cover requirements. There is no doubt however that XD3 (where de-icing salts are foreseeably to be used) in both Standards would be applicable because the steps and seats will cyclically be wet and dry from rain and snow and, based on my findings above, there would be salt used for de-icing them in winter. It is also foreseeable that de-icing salts could be used by the City Council on the roads and pavements in the immediate areas around the amphitheatres so further salt could be walked into the concrete of the steps and seats. BS 8500 would call for 45 mm reinforced concrete cover for both the southern and amphitheatres with an XD3 classification. The other Standards would call for 30 mm cover for "slab" bars and 35mm for "other" bars.
69. There was a major disagreement between the experts about the XS classification with Mr Wasilewski and Dr Roberts saying that XS1 was the appropriate classification under either Standard whilst Mr Tutt was of the view that something between XS1 and XS3 applied to the northern amphitheatre and XS1 to the southern. The argument revolved around in effect whether or not the northern amphitheatre could be considered as being within the splash and spray zones. The Mersey which is tidal and is about 26 m plus from the side of the northern amphitheatre. In Mr Tutt's judgment, this is within the spray zone because when the tidal and weather conditions are at their worst there will be sea spray from the tidal river which will splash or otherwise spread over or to the seats and steps. Whilst one can not suggest that the northern amphitheatre is a marine structure (as referred to in BS EN 206-1: 2000), it is at least sensibly arguable that the seats and steps comprise reinforced concrete surfaces within the splash and spray zone.
70. Whilst none of the experts suggested that these British Standards are to be considered as laying down absolute requirements because professional judgement needs to be exercised, it is my view, based on the evidence principally of Mr Tutt, that competent consultants would always err on the side of caution particularly with a building like the Museum and one in this particular location. XS1 would call for 25 mm cover whilst XS3 would require 35 mm or more.
71. The real problem here was that AEW simply never applied its mind to assessing, let alone understanding, what the requirements for these steps and seats should be. If it had done so, I am satisfied that, if it had acted competently and with reasonable care, it would have specified at least a minimum life of 50 years and that there should be specification requirements which erred on the side of caution to secure that minimum life. Thereafter, whether those requirements were drawn out by it (as being part of the architectural work) or they had been drawn up on a delegated basis by Buro Happold, a minimum cover of 30 mm and probably 35mm should and would have been called for. This reflects the XD3, XF4 and XS1 to XS3 exposure classifications which would and should have been adopted. AEW simply failed to exercise any reasonable care and either it failed to design and specify or secure by co-ordination a design and specification from others which would provide an effective minimum 50 year life.
72. As a matter of fact is clear that none of the seats and steps have been designed or constructed with significantly more than 25 mm cover. Indeed there is evidence which I accept that a significant quantity (about 10%) of the steps and seats did not even meet the 25 mm cover. There were two surveys done, one by a company called Celtest and another by SEP. There is broad acceptance that the Celtest cover-meter survey is reasonably reliable and demonstrates a much smaller percentage of units with less than 25 mm cover. I accept that the SEP survey has not been demonstrated to be necessarily reliable because there is no evidence either that this was an effectively accredited organisation or as to how the survey was done and with what equipment. It provides however some corroboration for the Celtest survey. That demonstrated that up to about 10% of the units did not even have the 25 mm cover.
73. A considerable time was spent at trial particularly by AEW's Counsel by way of cross-examination to determine how it even came about that 25 mm cover was selected. There was a document management system to which all the consultants had access whereby, amongst other things, the Contractor could and did file drawings and calculations either from itself or Rowecast for approval. It was Rowecast which came up with the suggestion that 25 mm cover should be provided. However, it all started with a Technical Query TQ 1382 dated 24 March 2009 from the Contractor addressed to AEW and Buro Happold which asked in relation to the amphitheatres stepped units:

"1. Please advise specification for reinforcement for step units

2. Please advise level of cover to reinforcement…"

Given that AEW had done nothing itself beforehand either to provide an appropriate specification for the steps and seats in question or to secure that one was provided, this would have been a yet further opportunity for AEW to ensure that a proper design or at the least the basic criteria therefor were laid down.

74. Prompted by Mr Rogers of AEW who wrote "BH response requested", Buro Happold replied on the 4Projects system that it assumed that the "reinforcement requirements will be detailed by the manufacturer as these are pre-cast step units". In my judgment, this involved an unjustified "passing of the buck" certainly by AEW and probably Buro Happold as well. The reason for this conclusion is that there was little or nothing in the building contract documentation which identified by reference to what standards or criteria the "manufacturer" (Rowecast) would produce its detailed design. Those were then followed by a Request for Approval from the Contractor in respect of the proposed specification by Rowecast which identified for instance what the concrete mix would be for these steps and seats and simply said "cover to reinforcement to suit aggressive exposure condition". Thereafter by a Request for Approval dated 7 July 2009, the Contractor sought approval for Rowecast's ramp and amphitheatre drawings. There was some coming and going on and these drawings were revised on several occasions with a request for final approval relating to Revision 3 addressed to both AEW and Buro Happold on 4 August 2009. Although the hard copy in the court papers needs a magnifying glass to identify it, the concrete cover was identified in the "Notes" as 25 mm cover. It is clear from disclosed e-mails that AEW (in particular Mr Rogers) regarded the whole design exercise as one for the Contractor and Rowecast; for instance, an e-mail on 5 August 2009 from him to Mr Saha of AEW said:

"It is Rowecast/PGT/BWSS design so don't get into providing solutions. You will run out of time – v quickly."

The Rowecast drawings then appear to have been approved or at least not disapproved. There is not one jot of evidence that suggests anyone from AEW or Buro Happold applied their minds to what should be the appropriate cover to provide at least a 15 year life for these architecturally important steps and seats features.

75. There was belatedly, indeed after the close of evidence, an application by the Museum to re-amend the Particulars of Claim to extend in so far as it was necessary the complaint about gaps to the slabs on the terraces above, abutting and behind the upper levels of seats and seats. There is no issue in reality that there were gaps of about 10 mm or more to the slabs on the terraces. The application is opposed by AEW on the basis that it is a very late amendment and that the cross-examination, defence and contribution proceedings were conducted at trial on the basis that the complaints about gaps in the terrace slabs were not pleaded.
76. There is undoubtedly authority for the proposition that the court should generally be reluctant to allow a very late amendment and that "a heavy onus lies on the party seeking to make a very late amendment" (for instance CD Court of Appeal case Swain-Mason v Mills & Reeve LLP [2011] EWCA Civ 14.
77. It is therefore necessary to consider the original Amended Particulars of Claim:

(a) Paragraph 7.1 describes the Museum as including:

"Two arrangements of precast concrete steps and seats (the "Steps and Seats") leading up to an entrance situated at each end of the Museum Building. The Steps and Seats and the terrace areas are collectively referred to in some documents as "amphitheatre steps" but are hereafter collectively referred to as the "Steps and Terraces.""

(b) Paragraphs 8 to 30 appear under a general heading in capitals "The Steps and Terraces. They describe problems with the "Geometry" of the Steps and Seats, the Cover to Reinforcement and at Paragraphs 26 and 27 "The Gaps between the Step/Seat Units". Paragraph 28 then complains that "AEW designed the Steps and Terraces in a manner which was deflected, referring to 2 possible remedial solutions set out in Appendix 7A.

(c) Paragraph 49 identifies AEW's breaches which included;

"The Steps and Terraces: Gaps between Concrete Units

49.12 [AEW failed to] take proper care to avoid producing and/or approving a design which avoided finger and heel traps…"

(d) Paragraph 14 9.22 pleads quantum related to "estimated works" set out in Appendix 10. Appendix refers to remedial works to the "Steps/Terraces".

(e) When the Museum responded to the Contractor's Request the Further information relating to the gaps between concrete units or 19 October 2012, it is clear that the particulars indicated by mention of gaps not only between and in the step and seat units but also the terrace units.

(f) There was no doubt that once the expert quantity surveyor reports were exchanged that work to resolve the gaps to the terrace was being claimed for. The quantum experts have had no difficulty in addressing the point.

78. The reality is that it does not particularly matter whether permission to amend is given or not because, as I find later in this judgement, the terrace slabs will in practice have to be taken up to enable the remedial works to the steps and seats to be done and then to be re-laid to make them compatible with the 5 mm or less gaps which are undoubtedly justified as part of the remedial works attributable to the negligence relating simply to the steps and seats.
79. I have little or no doubt that the Defendant had a very good idea that the pleading in the Amended Particulars of Claim was always intended to cover complaints about excessive gaps to the terraces. The breach in Paragraph 49.12 specifically related to "Steps and Terraces"; the quantum clearly was intended to relate to the Terraces also. If one was construing the Amended Particulars of Claim, one would in any event probably say that a case was sufficiently pleaded in relation to gaps in the slabs on the Terraces. Therefore, the amendment is clarificatory only. I can not see any prejudice at all about this. The experts in the different disciplines have looked at gaps as an issue relating to the seats, slabs and terraces. If AEW had succeeded in avoiding liability in respect of the gap problem to the seats and steps, that success was extended to the terraces. It is the same issue. I can not see that AEW or its legal team would have done anything different to that which they did during the course of this case. Although the application was very late, it had been signposted on the first day of the trial after Mr Reed QC raised the point.
80. I am fully satisfied that AEW failed to discharge their duties in relation to the steps and seats (and terraces) which were architectural features and within their contractual sphere of design responsibility. It failed to design or procure the design of the steps and seats. Even though reinforcement detailing and placement was the contractual responsibility of the Contractor, it was up to AEW to provide or procure the provision of the requisite design criteria to enable the Contractor to design effectively. It also failed, having delegated its responsibilities at least in part in relation to the approval of the Rowecast drawings to Buro Happold, to ensure that Buro Happold had actually applied its mind to the important question as to whether those drawings, particularly in relation to concrete cover, provided sufficient to secure that steps and seats as designed would provide a minimum life of 50 years. In these respects, AEW not only failed to do what it was employed to do but I am satisfied and find that it failed to exercise any let alone reasonable care in relation to the whole issue of concrete cover.

Liability (Contractor)

81. The Contractor is not liable in relation to the geometry of the steps and seats. That has now been conceded by AEW.
82. In relation to the gaps, AEW suggests that the design of the steps and seats was part of the works which the Contractor was required to design. This is, simply, wrong. The construction contract identifies those parts of the Works which the Contractor was required to design or have design involvement with as: "steelwork connections, reinforcement placement & scheduling, general glazing & curtain walling, roof cladding, fixing wind posts, structural glass and glazing". This is described in the contract as the "Contractor's Designed Portion" and it is simply in relation to those works that the Contractor has any design responsibility. There is nothing in the construction contract that suggest any of the words used in this description was intended to encompass the steps and seats, other than in relation to "reinforcement placing and scheduling"; that phrase can not and does not encompass the location and sizing of gaps between the units. That conclusion follows on not just from the words of the phrase but also because the sizing and location of gaps between the steps and seats impinges upon the aesthetics as well as on drainage requirements in relation to rainwater (none of which were the responsibility, design wise, of the Contractor). Sadly, the fact that from early 2009 if not before onwards AEW seemed to have believed that it had no responsibility for any aspect of the design relating to the steps and seats may well explain why this part of the work went so seriously wrong.
83. It is difficult to criticise the Contractor for putting forward the 10 mm gap because no gap was specified by AEW and I can only presume that it was put forward by Rowecast through the Contractor as a suggestion for AEW to accept or reject as the case may be. I can not say on the evidence that the Contractor was in breach of the construction contract for putting this forward because the size of the gap was not part of it is design obligation. If it had been, I would be in no doubt that the Contractor was in breach because it would then carelessly have put forward an excessive gap.
84. What actually happened was that Rowecast through the Contractor submitted drawings in the summer of 2009 which showed, at least in places, gaps of 10 mm which AEW saw and in effect approved; certain it is that it failed to disapprove. The only other complaint maintained by AEW against the Contractor is that it fitted the step and seat units in many places obviously with more than 10 mm. Although doubtless as a matter of workmanship there would be some allowable tolerance on the gap of 10 mm, it is undoubtedly the case that the Contractor was in breach of contract for failing to fit the units even within a reasonable tolerance in a significant number of cases.
85. In my judgment, the Contractor was also in breach of its construction contract with the Museum with regard to concrete cover for the reinforcement in the step and seat units not only because it or its sub-contractor failed even to comply in a not insignificant number of instances with the 25 mm cover requirement but also because it failed to exercise reasonable care and skill in designing or completing the design of the reinforcement in the seat and step units. Material clauses of the construction contract are as follows:

"2.1.2 For the purpose of so carrying out and completing the Works, the Contractor shall, in accordance with the Contract Drawings and the Specification/Schedules of Work where and to the extent that the same are relevant, complete the design for the Contractor's Designed Portion including materials and goods and workmanship to be used in the construction of that Portion so far as not described or stated in the Employer's Requirements or Contractor's Proposals…

2.7.1 Insofar as the design of the Contractor's Designed Portion is comprised in the Contractor's Proposal and in what the Contractor is to complete under clause 2.1.2 and in accordance with the Employer's Requirements and the Conditions…the Contractor shall have in respect of any defect or insufficiency in such design the like liability of the Employer, whether under statute or otherwise, as with an architect or, as the case may be, other appropriate professional designer holding himself out as a competent to take on work for such design who, acting independently under a separate contract with the Employer, had supplied such design for or in connection with works to be carried out and completed by a building contractor not being the supplier of the design.

86. There being nothing in the Employer's Requirements or other construction contract documents which clearly spelt out either what concrete cover was to be provided or specific or express criteria against which the concrete cover should be determined for the steps and seats, it was incumbent on the Contractor to complete the design which it chose to do via its sub-contractor, Rowecast; it needed to do this with the reasonable care and skill called for effectively in Clause 2.7.1. Between them, they chose 25 mm cover for the reinforcement and proffered that for approval to AEW and Buro Happold. In my judgment, that was a careless and negligent proposal in effect for the same reasons as AEW has been adjudged negligent. Although to be fair to the Contractor it sought a specification for the amount of cover (see above), it took upon itself the job of specifying the cover itself and it was in that sense "completing" the design.

The Ceilings

87. Liability is admitted by AEW in respect of the SAS ceilings.
88. In relation to the Armstrong ceilings, Mr Jowett's evidence (primarily set out in his report at paragraph 5.2) was not seriously challenged and Mr Pepper was entirely unconvincing. Mr Pepper apparently prior to giving evidence had not given any thought to responsibility for what had clearly gone wrong with the Armstrong ceilings. He did however confirm that there were numerous workmanship defects and that the ceilings were not installed in accordance with Armstrong's requirements.
89. I prefer and accept Mr Jowett's evidence. These ceilings had not been installed properly or carefully because the edge tiles did not have any Armstrong support; instead they rested on the lighting track, which must have come about because the ERCO lighting track had been integrated within the ceilings support grid without any attempt being made to adjust the ceiling grid dimensions so that a concealed edge support could be incorporated. Furthermore, in the Armstrong ceilings in the lobbies, the tiles were clipped to hold down onto the ceiling grid using only relatively weak proprietary spring clips which were insufficient to accommodate differences in air pressure between the lobbies themselves and the ceiling voids when doors are opened. The first deficiency resulted in there being no support on one side of the tiles and the second deficiency led to the tiles in the lobbies becoming dislodged as the clips could not hold the tiles in place. These deficiencies are obviously dangerous ones in that falling tiles could injure pedestrians below.
90. I am satisfied that no competent architect exercising reasonable care and skill could, should or would have allowed these deficiencies to be incorporated or remain in place. There are here essentially at least two failings, the first being a design and coordination failure on the part of AEW in failing to appreciate that that which was being proposed was inadequate and unsafe and the second being a failure to pick up the widespread deficiencies in its periodic inspections of the ceiling works. Although the point was hardly argued in closing by AEW's Counsel, cross-examination of Mr Jowett had proceeded on the basis that in effect because the ceiling installations were and would have been done over a relatively short period of time and even a competent architect might well have missed the otherwise very obvious deficiencies. This case was not ultimately clearly supported by Mr Pepper who was reduced to suggesting that one could not expect an architect inspecting the ceiling works to have noticed anything from ground level, bearing in mind that the ceiling tiles were some distance from the ground. I have no doubt that any competent architect should have made arrangements to inspect the ceiling tiles, albeit of course not every square metre thereof but such an architect should have inspected from time to time to see not only broadly what was being installed and how it was being installed but also to inspect each ceiling. Mr Pepper's point about the ceilings being too high is simply a bad one because architects with a responsibility to inspect with reasonable care must put themselves in a position (physically) where they can inspect. If that means they have to climb a scaffold tower or a ladder or even use binoculars, that is what they have to do. However, he accepted in evidence that a competent architect should inspect the ceiling tiles from whatever distance was necessary to enable him or her to see that they were being properly erected; when given the opportunity to reconcile this with his other evidence that the inadequacies could not have been seen from the ground, he merely said that the two propositions were not "easily reconciled".
91. I am satisfied that, if AEW had inspected, carefully or at all, the Armstrong ceilings, it would immediately have seen that they were being installed carelessly and in a potentially dangerous way. If it had done, carefully or at all, any design coordination work, they would have seen that what was being proposed would produce an unsuitable installation and a potentially dangerous one. There is no evidence to suggest that AEW did inspect these ceilings at all and, indeed, the fact that the ceilings were extensively defective suggests to the contrary that it probably did not inspect at all. It is common ground that there was plenty of time to inspect because the ceiling works were done over a period of weeks.
92. It follows that liability in relation to the Armstrong ceilings has been established on a balance of probabilities.

Quantum (General)

93. It is and was extremely unfortunate that there was until belatedly in the final throes of the trial no agreement at all on the numerous heads of quantum. Even after the quantum experts at the Court's urging produced a second joint statement, there remains little that has been agreed. For instance in relation to the 22 items applicable to the steps and seats there is agreement only on three items.
94. AEW's Counsel have repeatedly and tenaciously put forward an assertion that, because (as they argue) there has been insufficient disclosure on quantum on the part of the Museum, the Museum's quantum case is fatally flawed. They put before the court correspondence between the solicitors going back for many months. I am by no means convinced that reference to what was said or requested historically in this litigation helps towards any resolution of quantum issues. A detailed and lengthy Request for Further Information was served on 11 January 2012 by AEW's solicitors on the Museum; this ran to 39 pages and Requests 133 to 143 addressed quantum issues. No order was made by the Court ordering these to be answered. In October 2012, the Claimant sought to answer the quantum requests in some detail with some three files worth of supporting documents being provided. There was little by way of real complaint thereafter from AEW's solicitors either about the adequacy of that Further Information thereafter or indeed in relation to disclosure, although there was some complaint that the Claimant was slow in identifying the name of its quantum experts. AEW's solicitors did write on 19 November 2012 referring to the fact that various of the particularised claims were not supported by invoices or were otherwise not substantiated but there was no hint or suggestion that further disclosure was sought. The witness statements were not to be exchanged for some four months thereafter. On 4 February 2013 AEW's solicitors again said that the Museum had failed "to fully substantiate its quantum claim". On 8 February 2012 the Museum's solicitors did provide some further substantiation.
95. However on 19 April 2013 the Claimant applied to adduce further factual evidence which related to quantum and in particular further witness statements from Mr Matley and Ms Granville. This was dealt with at the beginning of the trial and was not opposed by AEW or the Contractor. Essentially, AEW's Counsel argue that the Museum has not provided all the requisite documentation necessary to prove its quantum, in relation both to historical costs and to future in-house or management costs and in any event its quantum is undermined by the absence of such documentation.
96. I have however formed a strong view that in particular Ms Granville's evidence on quantum is reliable and, even if not supported by every conceivable contemporaneous document that might otherwise have been disclosed, largely probative, particularly supported as it was by other witness evidence and by expert evidence.

Quantum (Steps, Seats and Terraces)

1. Remedial scheme - Basic Cost

97. The primary remedial works are yet to be done. It follows from my earlier findings that the geometry problem cannot readily be rectified simply by resorting to AEW's designs. It is clear that all the step and seat units need to be replaced because the reinforcement cover is insufficient to provide a 50 year life; they need to be taken away and disposed of and new units provided. All those units would in any event (as is now accepted by all experts) have had to be taken up not only because the gaps were too wide but also to determine whether there was insufficient cover to the reinforcement on those parts of the units (such as the undersides) which could not be checked in situ. As all the units have to be replaced in any event, no such checking needs to be done because in effect they are all condemned by reason of a clear under-allowance in the design for concrete cover. This disposes of a number of arguments such as whether some of the units could be set aside for re-use and could be stored on some temporary site close to the Museum; I would have found in relation to this latter issue that it was not safe or reasonable to assume that there would be an appropriate storage area at a realistic cost (if at all) close to the Museum.
98. I next turn to the scope of the remedial works and, on analysis, there is little difference between the parties. Mr Jowett has recommended that, assuming that they all need to be replaced, all the units should be stair-shaped but with step units laid on the seat units where steps are currently located. This is different to what is currently there which has larger seat units and stairs on stairs but the Jowett scheme will produce something which looks identical to what AEW and its Danish predecessor planned and for which planning permission was obtained. There will have to be specially designed, manufactured bevelled and chamfered units at the junction line to ensure a symmetrical and non-clashing fit. Mr Jowett explained in a convincing way particularly by way of oral evidence why this was a sensible and reasonable solution; a primary reason was that the use of a single basic double height unit similar in size to the current seating units would engender a greater chance of securing an effective, simple and readily achievable mitred valley intersection between the step and seat areas. I accept that his recommendation is a reasonable one, albeit that there were some relatively technical challenges to his recommendation, such as how one would secure the steps onto the larger units. I am satisfied that these technical problems could be readily overcome as the detailed design is worked out and that the remedial scheme proposed by Mr Jowett is readily achievable. It will be reasonable in achieving what the Museum always expected in relation to these two amphitheatres.
99. There is one other main difference between the parties in relation to the scope of remedial works, which relates to whether or not a second membrane should be provided in circumstances when it is now accepted on all sides that it was not negligent of AEW to specify or endorse the use of a single membrane in the first place. I have formed a very clear view that it would be sensible and reasonable for a second membrane to be provided and to be recoverable as part of the damages. My reasons are as follows:

(a) It is inevitable, based on what happened in 2009 when there were numerous leaks and punctures to the membrane as work was done on the membrane and units were manoeuvred into position onto the membrane, that, even if reasonable care is exercised by operatives, there will be further extensive damage to the existing membrane.

(b) Mr Jowett's scheme itself specifically involves cutting away membrane at the top of each inclined rib and in the area of a new concrete up stand at the valley junction.

(c) Although the units immediately around the valley were removed in 2010 or 2011 and no leaking has since been reported in the internal areas under the amphitheatres within the Museum, there is a very real risk, in my judgment based on the evidence, that this already much repaired existing membrane will be further damaged by the removal of the hundreds of remaining heavy units, by work people walking over the membrane when it is fully exposed and by the re-manoeuvring of the new units.

(d) A second membrane to be laid over the first and lower membrane will give reasonable added assurance that the Museum will not suffer leaks to the areas below. One reminds oneself that the Museum has only been put into the position of having to replace these very heavy units as a result of the negligence of AEW and it is not reasonable to expect the Museum to take the real risk of leaving the old single membrane in position which might well be further damaged by the indelicate operations involved in the remedial work. It is argued by AEW and the Contractor that the remedial work contractor would be responsible for not damaging the existing membrane and would be responsible for repairing further punctures and tears. The problem with this argument is that it does not take into account the real risks involved and the fact that the remedial works contractor would probably price in additional cost contingencies to the extent that it was asked to take the risk of being responsible for any further damage to the existing membrane; there is much less chance that it would price in such contingencies if there was to be a second and new membrane to be added.

100. There has been an issue as to whether the Amended Particulars of Claim cover the complaint about gaps to the terrace slabs. Irrespective of whether permission to amend was or is granted, it is unavoidable physically that when the steps and seats, particularly those abutting the terraces at the top, and that one or two rows of slabs will have to be removed from the terrace to facilitate the removal and avoid the risk of damage to the slabs themselves. The quantum for the remedial work includes just over £43,000 for re-laying the terrace slabs so that the gaps of 5 mm or less. In my judgment, it is likely that the relaying of those slabs will be required in any event and reasonably so, for two reasons. Aesthetically, it would be inappropriate on this prestigious building for the visual lines formed by the gaps within the steps and seats areas to be twice times (or more) narrower than on the terrace. Secondly, if one or two rows of the terrace slabs have to be taken up in any event, they can and should reasonably be relayed with safe gaps and it would then be wrong to leave the rest of the terrace with unsafe gaps.
101. In the Second Joint Quantum Statement, the quantum experts have in relation to the actual work to be done agreed a substantial number of figures or figures in relation to Mr Jowett's scheme. The total for the work exclusive of various additional items and add-ons is £369,002. I will only address those reductions in respect of which issue is taken:

(a) £542 reduction for disposing of less units: this reduction will not be allowed because all units need to be disposed off site.

(b) £1,473 for cutting membrane and forming new concrete upstand the valley junction: I accept Mr Jowett's evidence that this is required and I do not accept Dr Robert's view on this.

(c) £1,800 for testing the entire membrane electronically: in my judgement, this work is necessary and reasonable. It had to be done when the Contractor originally did the work and particularly after repairs.

(d) £1,500 for repairing any leaks: it is inevitable that there will be some leaks and punctures and repairs will be required to the membranes. £1,500 is a reasonable allowance which it is probable that any tendering contractors will build into their prices in any event.

(e) £20,481 for laying a second membrane layer: this should be allowed for the reasons given above.

(f) £5,728 for laying proprietary protective boards to entire membrane: this is a reasonable allowance because protective boarding will be required to prevent or limit damage to the lower and the new membrane layers.

(g) £19,080 for re-using some seat units: I do not consider that it is reasonable to expect any of the old seat units to be re-used.

(h) £30,922 for the use of stainless steel reinforcement: it has not been suggested that it was negligent or inappropriate to use ordinary (as opposed to stainless) steel reinforcement in the first place. I am not satisfied that using stainless steel is either reasonable or necessary. If an appropriate concrete mix is used with 35mm cover, that on the evidence should be an adequate remedial solution which should, all things being equal, produce a repair free life of 50 years. I would therefore not allow this.

(i) £750 for cleaning re-used units: there will be no re-used units.

(j) £13,300 for replacement handrail to the valley: as it was never intended for there to be such a handrail but simply a valley created by the junction between the steps and the seats, this should not be allowed.

It follows that the total sum of £369,002 should be reduced by £30,922 and £13,300, producing an allowable sum as damages of £324,780 for the actual construction works.

2. Preliminaries

102. There is agreement between the experts that it is appropriate to make an allowance for preliminaries type items relating to these remedial works; they also agree a one-off cost for mobilisation to and demobilisation from the site of £12,000 and a weekly rate of £3,175. The issues surrounding preliminaries relate to how long these remedial works are going to take. Mr Jowett is of the view that they will take 26 weeks and possibly even more. I found Mr Jowett's evidence on this convincing. He broke down the 26 weeks plus in to the different components of work and activities and all the periods seem to be reasonable and realistic. He was supported in practical and general terms by Mr Hemmings who saw how matters progressed during the original construction works. He thought that each amphitheatre would take about four months. He was of the view that it would be difficult to have both the North and South amphitheatres being worked on at the same time by reason of the access problems; this was to do with the need to keep the building opened to the public, to maintain deliveries to and from the Museum and to keep access available for the emergency services if required. He particularly referred to what he called "the narrow gap on the south-east corner" in the context that, whilst works were going on to the southern amphitheatre, access would need to be maintained around the northern amphitheatre. I broadly accept the evidence of Mr Jowett, supported as it was by Mr Hemmings, that it would be safe, prudent and reasonable to allow at least 26 weeks. Mr Jowett said that six months will accommodate the remedial works to both amphitheatres. Although there was some other evidence which suggested a longer period and there is undoubtedly a real risk that the works might take longer, 26 weeks is a reasonable allowance. Therefore, damages for preliminaries should be £12,000 for the mobilisation and demobilisation plus 26 weeks times £3,175, namely £94,550.

3. Site security

103. The next item relates to the site security during the remedial works. There will undoubtedly have to be site security. Not only must the working area to and around the amphitheatres be hoarded but also it will be necessary to ensure that access into the working area and indeed into the Museum itself from the construction site can not occur during the day, at weekends or at night. Apart from a vandalism risk, it must be borne in mind that the execution of these remedial works may well attract criminal interest not only with a view to pilfering from the construction site but also theft from the Museum through the construction site areas. Mr Fitch in his first report based his assessment on the allowance made by the Museum in relation to site security which covered the period from about Christmas 2009 through to June 2011 whilst little or no work was done on the amphitheatres albeit that it was boarded up and the site security was provided. The real issue on analysis between the quantum experts relates to whether or not the preliminaries allowance is sufficient, given that the remedial works contractor will have to provide some hoarding around the areas whilst remedial works are going on. I have formed the view that there is something in what both Mr Fitch on the one hand and Mr Matthews and Mr Raybould on the other say. The allowance endorsed by Mr Fitch is £5,991.53 a month but that assumes that the remedial works contractor would not be providing any hoarding. There will have to be additional security over and above what a remedial works contractor would ordinarily be expected to provide as part of its preliminaries. It would be reasonable for the Museum to retain additional security guards and to call for an enhanced level of security fencing over and above what the remedial works contractor would ordinarily provide. I have formed the view that a reasonable additional allowance would equate to £3,000 a month which, given that the remedial works after 26 weeks or six months, would produce a proper allowance of £18,000 in total.

4. Design Reserve / 5. Contingency / 6. Design/local authority and building control fees

104. There then follow three allowances for "Design Reserve", "Contingency" and for "design/local authority and building control fees", for which Mr Fitch allowed 10%, 10% and 15% respectively. There were differences between the experts on this with Mr Matthews allowing 5 to 7.5%, , 5% and a lump sum of £50,000 respectively and Mr Raybould allowing 0%, £10,000 and £27,900 respectively, although some of these are not absolutely directly comparable. I have formed the view that it is legitimate to allow a "design reserve", which essentially involves the likely and foreseeable additional costs which will emerge when the design is worked up in detail. The design at the most is at its initial stages and is in the form of a conceptual design which, as indicated above, is a reasonable and realistic one. However, as the design is developed and as is common, it is probable that additional detail will emerge which will dictate likely additional cost. Without intending in any way to adopt a judgment of Solomon, I take 7½% as a reasonable and fair allowance, coming as it does at Mr Matthews' upper end and at the mid-point between his lower range and Mr Fitch's 10%.
105. In relation to contingency, the quantum experts in their first joint statement agreed that it was usual and appropriate to make an allowance for unforeseen issues, as opposed to design developments or client's changes of mind. Certain it is that contingency is regularly allowed by quantity surveyors in estimating future costs on the basis that the unforeseen often happens. In this case, an allowance for contingency is particularly apposite for a number of reasons. The first is that there has been much local publicity about the problems associated with the Museum and any remedial works contractors, even if presented with fully detailed designs and specifications which are eminently priceable, will be aware that the Museum will be, wholly understandably, an exacting client which will be determined to ensure that the previous mistakes are not repeated. It is therefore foreseeable that there may well be a premium to pay for that type of consideration even though judged by pricing estimates beforehand the tender costs should be less. Secondly, these works will be carried out to and around a functioning museum which is open to the public and is a landmark; there will have to be additional liaison and not just with the local authority and building control but also with the Museum to ensure the smooth running of and access to the Museum. That is going to add to the construction costs. The third factor involves the risk that the construction period will exceed the 26 weeks upon which I have based the preliminaries assessment; although it is not certain, there is undoubtedly that risk and contractors may well price that risk even if only a 26 week period is specified. I have formed the view that an appropriate allowance is much closer to Mr Fitch than to either Mr Matthews or Mr Raybould. I have therefore allowed a reasonable allowance of 8%.
106. The final allowance for design/local authority and building control fees involved fee costs associated with the design of the remedial scheme and the approval of the design of her immediate scheme. It was agreed in the first quantum joint statement that it was appropriate to make an allowance for local authority building control fees as such. Mr Raybould allowed £5,000 for building control fees.
107. The real area of dispute here revolves around the extent to which the Museum would be acting reasonably and sensibly in retaining a professional design team. In my judgment, there can be no rational or reasonable alternative other than it would be wholly reasonable and sensible for the Museum to retain architects and engineers although the extent to which some of their functions might overlap is unclear. The defending parties' experts did themselves a disservice and undermined their credibility by suggesting as realistic the need to retain simply one engineer to perform all the relevant functions and, indeed, if the remedial works contract was let as a "design and build" contract, the client engineer would at best have a checking function for the contractor's engineers. First, it is important and reasonable that the Museum, which has already experienced serious problems as a result of the negligence of AEW, retains direct control and influence over the designers. Secondly, there are extensive architectural and engineering functions to be performed. Thirdly, it is vital that there is close liaison between the consultants and the client, bearing in mind not only the history but the need to maintain the running of the Museum. Fourthly, it is not wholly irrelevant to that the original project was fully staffed by independent consultants and there is no hint or suggestion in the contemporaneous documents that anyone suggested that the Museum was overstaffed by its consultants. I have no hesitation in finding an allowance of 15% is reasonable and realistic.

7. Inflation allowance

108. In addition to this, it is common ground between Mr Matthews and Mr Fitch that because the remedial work costs on which they had been working were prepared at prices prevailing some months ago an inflation allowance of 2.3% is reasonable and realistic. I agree.

8. Abortive installation of plinth upstand

109. The next item is agreed and relates to the money paid and payable to the Contractor in relation to CVI 340 which called, by way of variation, for the construction of what Ms Granville called the "abomination", namely the plinth or upstand over the valley between the steps and seats. This was a waste of money in that it was not a proper solution and it was not and never would have been approved. The quantum is agreed at £67,936.96.

9. Removal of plinth

110. There is then in similar vein the removal of the offending plinth which was carried out by the Contractor in 2010. Again for similar reasons, this is and must be recoverable and the quantum is agreed in the sum of £12,948.27.

10. Security costs

111. There is a claim for the cost of additional security attributable to the delay following the construction of the plinth. The Contractor retained G4S to provide security during this period. The first issue relates to what caused the delay between the end of 2009 and the date when the building was handed over to the Museum in July 2011. The evidence points very strongly to there only being one effective and certainly dominant cause of the delay, namely the problems with the steps and seats. Mr Matley gave some clear evidence about this, as did others. There was only one other factor which might be thought to have come into play and this had to do with the combined heat and power system which was finally sorted out by about October 2010; however, the building had been tested and commissioned on the basis of a temporary power system that was running certainly by the time that the inside of the building itself was handed over to the Museum in about February 2010. It is therefore unlikely that the sorting out of the CHP system critically delayed the works. From 18 January 2010 until July 2011, I find that the cause of the delay was the negligence of AEW with regard to the geometry of the steps and seats and the execution of the CVI 340 work. The suspension of work which was reasonable and necessary in all the circumstances arose as a result of that negligence and therefore AEW is responsible for and caused the subsequent delay. There has been no suggestion that the Museum caused any delay during this period or indeed that the Contractor was to blame.
112. There is unchallenged evidence that £95,709.67 has been paid by the Contractor to G4S with regard to these security services and there is no suggestion that it was unreasonable or unnecessary to deploy these services or that the sums paid out by the Contractor were excessive. The sum has not yet been paid by the Museum to the Contractor because there is an outstanding dispute between the Contractor and the Museum under the construction contract as to whether or not the Contractor is entitled to an extension of time and to financial reimbursement in respect of the period of delay to which these security service costs apply. The only issue is whether or not justice is best served by ordering that this sum should be paid or payable now as damages or by ordering AEW in effect to indemnify the Museum against any liability which it might have to the Contractor in relation to such sum.
113. There is an undoubted logistic and forensic problem. Little or no evidence was advanced, either by way of witness or expert evidence or by way of documentary disclosure justifying the Contractor's financial entitlement to this sum under the construction contract. I pressed Mr Lee at several stages in relation to such claims to identify whether his clients were prepared in effect to limit themselves to that which had been claimed or at least that which was identified by the Museum in its pleading as having been claimed. On instructions, he was reluctant to do so. There is a substantial claim for extension of time and related loss and expense by the Contractor and no part of the evidence supporting it was deployed by the Contractor in this case and, so far as I can ascertain, no or limited disclosure in relation thereto had been provided.
114. Although I have made findings (see above) that the delay from January 2010 to July 2011 was attributable to and caused by the negligence of AEW, it may not automatically follow that the Contractor's claims will succeed at least in full or for the full period. It may for instance be the case (and I only speculate) that some of these security costs might be attributable to whatever the problems were with the CHP system. Another possible area of issue might relate to the recoverability under Clause 26 of the construction contract conditions of all or part of such sums; this clause permits the recovery of loss and expense caused by certain matters including Architect's instructions and postponements but there is a condition precedent that the application for reimbursement must be made "as soon as it has become, or should reasonably have become, apparent to [the Contractor] that the regular progress of the Works…has been or was likely to be affected". It may be, and there simply has been no evidence one way or the other, that this condition has not been complied with. It remains the case however that there has been no resolution between the Contractor and the Museum in relation to such claims.
115. Reference has been made to various authorities which, however, do not lay down any great principle. I would suggest the following:

(a) It is obviously in the interests of justice for there to be finality and the Court should, generally, strive to produce a final judgement which finally disposes of the matters is in issue, including the final assessment of all damages or other compensation payable.

(b) However, justice also demands that an innocent claimant which is clearly and obviously entitled to damages should be fully and adequately compensated, obviously within the legal rules and constraints in relation to the recovery of damages.

(c) There may be circumstances in which the Court must, to ensure justice to the innocent claimant, take appropriate steps to secure that it is adequately compensated.

(d) If the Court is of the view that there is a real likelihood that there will be heads of loss which can not be quantified by the Court at the stage at which the Court is being asked to fix compensation, the Court in effect has three options: make a very broad damages assessment in respect of those heads, postpone that assessment until further information is available or grant a declaration that the innocent claimant is entitled to be indemnified by the defendant which is liable against the losses in question.

116. One of the real difficulties here is that it is common ground that there is an arbitration agreement between the Contractor and the Museum and, understandably, the Contractor is not prepared to agree to bring any disputes relating to delay and delay related compensation into court; it is of course contractually entitled to take this stance. If there was such agreement, I would have been minded to postpone the assessment of delay related losses said to have been incurred by the Contractor, on the basis that AEW could then participate if it so wished in the requisite court proceedings.
117. It is very difficult for the Court to take an evidential leap and try to assess what these delay related losses are or what the Contractor will prove. In relation to the G4S security costs, I can and do find that they had been incurred and they have been incurred in relation to the January 2010 to July 2011 period where the delay was caused by the negligence of AEW. In the surprising absence however of the requisite evidence from the Contractor in these proceedings to support its delay related claims for this period and in the absence of any argument about its entitlement or disentitlement to delay related compensation, the Court is left in a real difficulty because, whilst it can see that compensation may well be payable by the Museum to the Contractor for the delays caused by AEW, it is insufficiently informed by detailed evidence let alone argument about the scope and extent of such compensation. Whilst the Court could theoretically simply say that the Claimant has not proved its case, that would be wholly unfair and contrary to justice.
118. In my judgment therefore, this is a case in which the Court should make a declaration in appropriate terms that the Museum should be indemnified by AEW against damages, losses, expenses or cost payable by the Museum to the Contractor by reason of the matters for which it has been found liable in these proceedings. This would not permit the Museum to recover sums which it has otherwise recovered as damages awarded by the Court. In line with normal principle (for instance by the application of the principles laid down in Biggin v Permanite), if the Museum settles with the Contractor, it may well have to establish pursuant to this indemnity arrangement that the settlement was in all the circumstances reasonable.

11. Loss and expense incurred by the Contractor in relation to prolongation

119. The next head of loss is "loss and expense incurred by the Contractor" in relation to prolongation. The Museum identified a figure of £171,314 as the claim made by the Contractor in relation to the period January 2010 to July 2011. The Contractor was in these proceedings "coy" about whether such a claim represented its full claim for the period; Mr Lee confirmed on Day 9 of the trial that the claim would be larger. The Contractor did not produce by way of disclosure its accounting and other documents which would identify what its delay and disruption related losses were for this period. For similar reasons to those set out above, this is the case for an appropriate declaration of indemnity.

12. Survey costs

120. Survey costs were incurred by the Museum in relation to the problems associated with the steps and seats. Quantum is agreed between the experts and indeed by the parties in the sum of £6,655.

13. Lawrence Bamber

121. A small item relates to a report prepared by a Mr Bamber on the external steps and terraces, for which £540.80 was invoiced and apparently paid. However, I can find no evidence (other than the invoice from Mr Bamber dated 12 March 2010) which explains what he did. Therefore, I find that this small claim has not been proved.

14. Site hoarding (2011 onwards)

122. £41,994.25 is claimed for the installation of site hoarding around the north and south amphitheatres. This figure is agreed as a figure by all experts. This covers the purchase of the hoarding. The only argument here is effectively that the Museum should not have called for the removal of the plinth because it could have remained in place until the required remedial works were carried out and in those circumstances the area could have remained open. It is also suggested by AEW that the hoarding could have been hired. In my judgment it can not begin to be said that it was unreasonable of the Museum to call for the removal of the plinth which, it is accepted, had been put in place as a direct result of the negligence and breach of contract of AEW and of AEW exceeding its authority in instructing that work to be done in the first place. There was no hint or suggestion made by anyone at the time (and certainly there is none in the documentation before the court) that the plinth should not be removed. The Museum had a right to expect that its consultants would come up with a sensible solution within a reasonably short period of time. It was only by the summer of 2011 that it was becoming apparent that no such ready or simple solution would or was going to be provided. Thereafter, the unchallenged evidence from the Museum is that it lacked the funds to embark on the substantial remedial works necessary. It was therefore essential from a health and safety as well as a security standpoint that the north and south amphitheatres should be hoarded so that the public could not gain access into what was a potentially dangerous area with most of the step and seat units around the valley having been removed by the Contractor. So far as I can ascertain, it was never put to the Museum's witnesses that it was unreasonable to purchase the hoarding or to deploy it and there was no specific evidence that the cost of hiring from 2011 until the time when the works are actually done (presumably now in 2014) would be particularly cheaper than purchasing. In my judgment, this claim has been proved and established and I am satisfied that there was no failure to mitigate.

15. Adana Construction

123. Another small item relates to an invoice from Adana Construction for removing defective step and terrace units in the sum of £1,553.48. This sum has been paid (on the evidence). It is clear from the confirmation instruction that this work was ordered in May 2011 by or on behalf of the Museum. I infer that this work relates to moving some of the steps and terrace units that had been removed from the amphitheatre by the Contractor and which were getting in the way of Adana who had to move them. This would not have had to have been done if AEW had not been negligent in the first place. There is no dispute on the quantification. The sum should be allowed.

16. Adjudicator's fees

124. The Museum claims for the fees of an adjudicator, Mr Derek Pye, who was appointed to adjudicate upon a dispute which had arisen between the Contractor and the Museum which broadly related to whether the Contractor had design responsibility in relation to the seats and steps in the amphitheatres. This was obviously a live topic between the Contractor and the Museum, following the problems which had emerged in January 2010. The claim encompasses the fee paid to Mr Pye (exclusive of VAT £19,830.66), £95,831.32 in relation to the Museum's solicitors fees in connection with the adjudication and £6,630 in respect of related fees of Turner and Townsend. The adjudication was initiated by the Contractor by a Notice of Adjudication dated 20 December 2010. The Contractors sought declaratory relief that the steps and seating did not form part of the Contractor's Designed Portion under the construction contract, that CVI 340 was a variation and that the Contractor was entitled to instructions to enable it to overcome the problems associated with the steps and seats. Extensive exchanges between the parties have followed the service of the Referral documents by the Contractor with a Response, Reply, Rejoinder, Surrejoinder and various other submissions. Statements from eight witnesses were submitted, there being 15 statements in total. The adjudicator decided the issues of principle in favour of the Contractor and ordered the Museum to be responsible for his fee. The Museum paid this sum.
125. The main issue between the parties in this case on this item revolves on analysis around reasonable foreseeability and causation linking AEW's breaches of contract and the adjudication. In simple terms, there would have been no dispute at all between the Contractor and the Museum if AEW had carefully designed or coordinated the design of the steps and seats. But for the breaches of contract and negligence on the part of AEW, the plinth would never have been or had to have been instructed and the works would all have been finished by about the end of 2009; there would have been no suspension of works and there would have been no need for any further instructions to be given to the Contractor. Construction adjudication was by the time of this project very well established and it was reasonably foreseeable that adjudication could be deployed by the Contractor in relation to wide-ranging and different types of dispute including the scope of design responsibility. The Museum was put in the position it was in relation to the adjudication by reason of the defaults of AEW.
126. The problem here however is arguably more one of causation. The Museum retained competent and experienced construction law solicitors (DWF LLP) in relation to the dispute which was ultimately referred to adjudication. True it is that shortly after the adjudication started DWF wrote to AEW on 23 December 2010, inviting it to cooperate in relation to the adjudication, even assuming it denied responsibility itself; it did write that: "if, in fact, you accept liability, then we respectfully request and require written confirmation of this admission by return". It is clear that the adjudication was keenly fought and, I must assume, that time and costs were not consciously wasted by the Museum and its advisers in fighting the adjudication on a basis that was considered to be unarguable. I must assume that the Museum and its advisers on an intellectually honest basis believed that there was an arguable case that the Museum was in the right, that the Contractor was responsible for the design of the steps and seats and that the Contractor was responsible for sorting out the hiatus that still existed. Essentially, AEW argues that it fought the adjudication knowing that, even if it was successful, it would not recover its costs, that the decision would only have temporary finality and that costs would not be recoverable from the Contractor in subsequent proceedings; Mr Reed QC argues therefore that AEW should not be liable to these costs in circumstances where irrespective of the outcome of the adjudication the Museum would not have recovered its costs, this being a backdoor method of cost recovery.
127. I have formed the view that these costs are recoverable. If AEW had done its job properly in the first place, it is inconceivable that there would have been any adjudication in relation to the design responsibility of the Contractor because the issue simply would not have arisen: there would have been no problem with the geometry, the reinforcement or the gaps; there would have been no need for any suspension and there would have been no delay attributable to the steps and seats in 2010 and 2011. Adjudication is a fact of life now in construction contracts, albeit that it is not invoked on every project. It was within the bounds of reasonable foreseeability that there could be adjudication in circumstances such as arose here. There was a sufficient causative link between the defaults of AEW and this adjudication. The causative link would only be broken if the Museum had acted unreasonably or if its solicitors had acted negligently in advising the Museum that it had an arguable defence in the adjudication. It has not been suggested that either of these eventualities arose. I therefore consider that this claim is a good one and has been established on the evidence.

17A. Legal fees in adjudication

128. Turning to the costs of the solicitors, copious bills and breakdowns have been provided and I infer at the very least that they have been paid by the Museum. However, there was no direct evidence explaining how and why the costs were all attributable to the adjudication and the immediate run up period. Ms Granville gave evidence about these costs and said that, although the solicitors invoices totalled £119,531.32, she had been advised by DWF that this should be reduced by £23,700 in relation to the pursuance of the claim against AEW. However, unsurprisingly, she herself could not explain or justify individual elements. The adjudication process ran from 20 December 2010 through to the issue of the adjudicator's decision on 21 February 2011. The invoices were as follows:

Invoice date	Period of work	Amount (ex VAT)
29 October 2010	13/9/10 - 25/10/10	£15,531
30 November 2010	Possibly 25/10/10 to invoice	£14,448.50
31 December 2010	2/12/10 -30/12/10	£19,000
31 January 2011	January 2011	£40,000
16 March 2011	2/2/11 – 28/2/11	£14,360
31 March 2011		£3,151.50
31 March 2011		£12,739
19 April 2011	Couriers (12/10/10 and 17/11/11)	£301.32
Total		£119,531.31

129. In the absence of a detailed explanation, the Court must make the best assessment that it can and in so doing it should adopt only the maximum figure which it is safe to infer reflected the reasonable costs, properly incurred in relation to the adjudication. In that context, my best assessment is £53,000 and calculated as follows:

(a) I exclude the first two invoices as being well before the actual adjudication and in the absence of evidence which makes it clear when adjudication was first threatened.

(b) I allow half of the invoice relating to work in December 2010 because by then the adjudication must have been intimated and indeed it was instituted. Substantial costs in adjudication do begin to be "racked up" at an early stage because it is such a short process and a defending party has very limited time to produce its responsive submissions.

(c) I allow 80% of the bill for work in January 2011, which was clearly a period of intense legal activity in the adjudication.

(d) Similarly I allow 80% of the bill for work in February 2011 for the same reason.

(e) In the absence of specific evidence as to the two bills dated 31 March 2011, I disallow them as not proven.

(f) I allow some £298.32 in relation to couriers for transmitting papers to the Contractor's solicitors and to the adjudicator on 17 January 2011.

(g) This produces a total of £53,286.32 (£9,500 + £ £32,000 + £11,488 + £298.32). I round this down to £53,000.

17B. T&T's time in adjudication

130. The next related head of costs claimed is Turner and Townsend fees in relation to the adjudication. Although this was claimed in the sum of £17,130, Ms Granville when giving evidence accepted that this needed to be adjusted downwards to £6,630. It is supported by an invoice and relates to 86 hours of work provided by Mr Matley and 16 hours from Mr Wood in relation to what is called "Steps & Terraces adjudication support & expert witness statements". It is recorded in the adjudicator's decision that two witness statements were submitted from Mr Matley and one from Mr Hewitt of Turner and Townsend. There is therefore corroborative evidence that this work was done. There is no suggestion that the rate claimed before Mr Matley is unreasonable (at £60 per hour for 86 hours) but there is no evidence as to what Mr Wood was doing. I therefore am satisfied that Mr Matley's time and rate are justified and related to the adjudication. £5,160 will therefore be allowed.

18. Professional Fees up to Practical Completion

131. This claim relates to additional professional fees paid by the Museum to Mace and T&T during the period from January 2010 to July 2011. Mace was the project manager for the project and T&T provided quantity surveyor and contract administrator services. Ms Granville gave the over arching evidence in relation to this claim saying that Mr Lawton and Ms Parker both of Mace and Mr Matley of T&T applied 90% of their time from January to March 2010 and 30% from April 2010 to June 2011, and Mr Hewitt 90% of his time for the earlier period and 10% thereafter in relation to the fallout and problems associated with the steps and seats. She then related these percentages to the relevant Mace and T&T bills for this period and claimed the resulting balance, namely £155,539.30. She based that on her own observations but also on what she had been told by these persons. Save for Ms Parker (who was not required for cross-examination but put in a statement), they were all called as witnesses. The main reason for the delay to the project in 2010 up to mid-2011 was the negligence of AEW. But Mr Matley confirmed in evidence this assessment in relation to his time but confirmed that the 90% assessment of his time dealing with the steps and stairs issue started on about 18 January 2010 following the "abomination" meeting. Mr Hewitt said in evidence that he spent about 50% of his time in the earlier period and slightly less in the later period. Mr Lawton in evidence said that he personally had not made the 90%/30% assessment but he said that he would estimate 75/80% in the earlier period and 25/30% for the later period.
132. These are clearly broad-brush assessments and one can not criticise the Museum simply for paying the monthly bills from Mace and T&T without calling for a detailed breakdown. It is possible, and indeed, for instance, Mr Matley did accept that his firm did have a time recording system. I am satisfied on all the evidence that it is probable that these four personnel from these two firms spent a considerable amount of time in 2010 and 2011 on the fallout from the steps and seats problems. Work included extensive back checking of designs, liaison with the Contractor in relation to the removal of the plinth and the step and seat units around the valley, advising and liaising with the Museum and its staff about the way forward and the like. I find that the assessments made in evidence by the witnesses who were actually involved are more likely to be reliable than those percentages recorded by Ms Granville.
133. There is however an area of doubt as to the base figures onto which these percentages should attach. An example is T&T's invoice for the cost management role ("CM", effectively Mr Matley) For January 2009 which is £9,000 for "shell and core post contract stage", whilst only £4,500 is identified in relation to the remaining invoices up to June 2011. There is no real explanation for this. In relation to the contract administrator role ("CA"), the T&T invoices to which the claim relates varies between £4,800 and £10,200 a month with no obvious explanation for the difference. On any assessment, it would be prudent to take the lowest figure.
134. I am wholly satisfied on the evidence that substantial time and cost was expended by the Museum on fees payable to Mace and T&T for professional services in this period dealing with and addressing the problems associated with the steps and seats. It is not possible to do a precise ascertainment but it is possible to do a broad assessment which I set out below:

T&T/Mace	Period	Calculation and Assessed amount
T&T CM	Jan 10	90% for 13/31 days @£4,500: £1,698
T&T CM	Feb-March 10	90% of £9,000: £8,100
T&T CM	Apr 10 – June 11	30% of 4,500 x15: £20,250
Sub-total		£30,048
T&T CA	Jan 10	50% of 13/31 @£4,800: £1,006
T&T CA	Feb-March 10	50% of £9,600: £4,800
T&T CA	Apr 10 – June 11	30% of £4,800 x 15: £21,600
Sub-total		£27,406
Mace	January 2010	75% for 13/31 @£10,400: £3,270
Mace	Feb-March 10	75% of £20,000*; £15,000
Mace	Apr 10 – July 11	25% of £10,000* x 15: £37,500
Sub-total		£55,700
Total		£113,154

* I have used a figure of £10,000 per month because there has been no explanation as to why what the time charges invoiced by Mace ran between £4,200 per month and £17,000. I have therefore used a rounded down median figure of £10,000 per month for assessment purposes on the basis particularly that Mr Lawton was obviously heavily involved in relation to the steps and seats in these periods and because there is no obvious reason for there to have been an increase over such a monthly charge specifically in relation to the steps and seats.

19. The Museum's Internal Management and Staff Costs to Practical Completion

135. There can be no doubt, and I find on the clearest evidence, that the Museum necessarily had to deploy staff to deal with, address and accommodate the problems associated with and consequential upon the steps and seats problem which emerged very openly on 18 January 2010. Ms Granville, who was herself intimately involved, identified how much time was spent in these activities by her, the Director of Estates (Mr Williams), the Project Assistant (Ms Green) and the Building Operations Manager (Mr Hemmings). She identified in evidence the pay grades and the salary cost per day for each of these four. I find, and indeed, there can be no doubt, that the time which these individuals spent in addressing the problems associated with the steps and seats would otherwise have been spent on other matters which would doubtless have inured for the benefit of the Museum.
136. There has been what might be described as essentially a forensic challenge by AEW's Counsel to what Ms Granville has said about this claim (and indeed what she has said about comparable claims in relation to Museum staff time). The argument suggests that the time assessments are suspect and too vague, and that there is a substantial amount of disclosure such as payroll and possibly diary records which could have been but were not produced by the Museum (pointing to a lack of hard evidence to support the time assessments and indeed the associated payroll costs). I am not impressed with this challenge, broadly for two reasons. The first is that Ms Granville was an impressive, believable and honest witness whose evidence I have no real difficulty in accepting, backed up as it largely was, at least in part, by other witnesses. In any event, she was not cross-examined as to credit and there was no suggestion that she was anything other than honest and competent. Secondly, whilst there may be cases in which the absence of underlying accounting documentation might undermine a party's quantum case (particularly where it was otherwise suspect), the supposedly missing documents such as payroll records were never sought on disclosure by AEW.
137. An even more thoughtful argument raised by Mr Reed QC however relates to the inherent recoverability of the payroll cost of employees of a claimant. There was reference to several authorities. In Aerospace Publishing Ltd v Thames Water Utilities Ltd [2007] EWCA Civ 3, the Court of Appeal was concerned with a case in which an archive had been lost as a result of flooding which was the responsibility of the defendant. One of the damages claims related to "payments made to staff for work necessarily done by them in relation to, and consequent upon, the flood" (Paragraph 73). Wilson LJ who gave the judgement of the court on this topic reviewed the authorities and said at Paragraph 86:

"I consider that the authorities establish the following propositions:

(a) The fact and, if so, the extent of the diversion of staff time have to be properly established and, if in that regard evidence which it would have been reasonable for the claimant to adduce is not adduced, he is at risk of a finding that they have not been established.

(b) The claimant also has to establish that the diversion caused significant disruption to its business.

(c) Even though it may well be that strictly the claim should be cast in terms of a loss of revenue attributable to the diversion of staff time, nevertheless in the ordinary case, and unless the defendant can establish the contrary, it is reasonable for the court to infer from the disruption that, had their time not been thus diverted, staff would have applied it to activities which would, directly or indirectly, have generated revenue for the claimant in an amount at least equal to the costs of employing them during that time."

138. Lord Justice Wilson also referred to the judgment of Mrs Justice Gloster (as she then was) in R + V Versicherung AG v. Risk Insurance and Reinsurance Solutions SA [2006] EWHC 42 (Comm) in which she said:

"77. In my judgment, as a matter of principle, such head of loss (i.e. the cost of wasted staff time spent on the investigation and/or mitigation of the tort) is recoverable, notwithstanding that no additional expenditure "loss", or loss of revenue or profit can be shown. However, this is subject to the proviso that it has to be demonstrated with sufficient certainty that the wasted time was indeed spent on investigating and/or mitigating the relevant tort; i.e. that the expenditure was directly attributable to the tort … This is perhaps simply another way of putting what Potter L.J. said in Standard Chartered, namely that to be able to recover one has to show some significant disruption to the business; in other words that staff have been significantly diverted from their usual activities. Otherwise the alleged wasted expenditure on wages cannot be said to be "directly attributable" to the tort."

139. A similar view was formed by Mr Justice Ramsey in Bridge UK Com Ltd v Abbey Pynford PLC [2007] EWHC 728 (TCC) in which there was a claim for management time incurred by the claimant's staff in dealing with problems caused by the defendant. He said:

122. At exhibit PR 33 to his witness statement Mr Peter Ruck has set out a schedule of the time spent from 31 August 2002 to 30 April 2003. In the main part of his witness statement he deals with the claim at paragraphs 79 and 80. He says that he calculated that he was engaged for 128 hours in dealing with the problems caused by the Defendant. As he explained in evidence the hours were based on his assessment of the time he spent on various matters. That assessment was made retrospectively. He prepared it by looking through the various documents which record what happened.

123. Such a method of retrospective assessment is, I consider, a valid method of calculation. I have been referred to the judgment of His Honour Judge Peter Bowsher QC in Holman Group v. Sherwood (Unreported, 7 November 2001) where he indicated that in the absence of records, evidence in the form of a reconstruction from memory was acceptable. I respectfully agree. However, it must be borne in mind that such an assessment is an approximation of the hours spent and may over-estimate or under-estimate the actual time which would have been recorded at the time…

125. I accept that the appropriate approach to the question of recovery of such management time is that set out by Gloster J. in R+ V Verischerung…

126. In this case Mr Ruck states at paragraph 79 of his witness statement and I accept that the Claimant "suffered losses due to lost opportunities since I was the New Business Development Director at the time, and I was unable to leave the premises in order to attend to other responsibilities such as selling and marketing the Claimant's business."

128. As a result, I am therefore satisfied from Mr Ruck's evidence that he spent time dealing with, investigating and mitigating the effect of the problems caused by the Defendant. That time amounted to 100 hours. Mr Ruck would otherwise have been selling and marketing the Claimant's business during that time. On that basis the Claimant is entitled to recover for 100 hours of Mr Ruck's time.

129. In this case Mr Jarvis has produced a short statement in which he as stated that from the audited accounts of the Claimant he has calculated the annual income of Mr Ruck in the relevant period to be £100,074.84. When this is divided by 2080 hours (equivalent to 52 weeks at 40 hours a week), it gives a figure of £48.11 per hour. Mr Jarvis is a qualified Accountant and I accept his evidence as to the accuracy of the calculation of Mr Ruck's income. On this basis I am satisfied that the sum of £48/hr claimed by the Claimant is appropriate.

140. I am satisfied that there was a substantial diversion of staff time in this 2010 to 2011 period to address the problems associated with the steps and seats and that, inevitably, that there was a substantial disruption to its business both in connection with the Museum in question but also the running of its seven other museums or historical buildings. There is nothing intrinsically wrong with the retrospective assessment which Ms Granville has done; she was closely involved in this period and was clearly taking a particular interest in these serious problems which were materially delaying the effective opening of the Museum. She was well placed to know how much time was spent at least in a general and broad sense.
141. Whilst I am by no means convinced that it is necessary as a matter of law to find that "staff would have applied it [their time] to activities which would, directly or indirectly, have generated revenue for the claimant in an amount at least equal to the costs of employing them during that time" (because Lord Justice Wilson was not limiting the loss, waste or application of management time claims in this way), I can and do make this inference. The reason is that the staff actually had other jobs to do other than cope with the fallout from the steps and seats problems. For instance, Ms Granville was and is in charge of eight buildings for the Claimant; they all generate income albeit that it is clear also that some income is generated from grants or charitable giving. Her time, for instance, could and would have been better spent doing things which undoubtedly would have assisted in the generation of revenue. If one also brings in her evidence that there were what she called "backfills", the justification for a recovery of management time becomes even more compelling. She said that, by reason of her involvement with the problems, other people took over parts of her other roles and there was a ripple effect with yet more people having to do the work which those other people did not have time for; she said that additional roles were actually created to fill the gaps that were left. She said that each of the people who took on additional duties were paid either a responsibility allowance or were temporarily re-graded to cover for her substantive role.
142. In my judgment, an innocent claimant which has established its cause of action can recover its management time reasonably spent dealing with the consequences of the negligence or breach of duty in question. Although it could be said that it would have to pay the salaries in any event to its staff and has therefore incurred no loss, the time of the staff is being deployed to remedy or otherwise address the otherwise recoverable loss and as a matter of causation it is equally being incurred for two causes, one the employment and the other the cause of action itself. This view is supported by Gloster J in the R + V Versicherung AG case.
143. In my judgment, the Museum is therefore entitled to recover for management time expended addressing at the problems associated with the steps and stairs. Turning to the quantification, it is fair and reasonable given the relatively general retrospective assessment done by Ms Granville to adopt a reasonably cautious approach. I broadly accept the assessment which she makes in respect of herself which is 36.5 days' worth of her time over the period but I reduce it to 30 days to reflect the fact that she said that she had discussed the percentages with Mr Williams, they had both looked at their diaries and that it was difficult to estimate how much time they had spent discussing the particular issue; she said elsewhere that she had done a "sense check. Although she was confident that at least this time was spent, I am satisfied that at least 30 days were spent by her; although it may well have been more, I can not be satisfied on the balance of probabilities that it was. The same can be said for Mr Williams and Ms Green for whom similarly 36.5 days were claimed; I allow 30 days in respect of each event. In relation to Mr Hemmings for whom 122 days are claimed, there is on the evidence a mathematical error which suggests that at most his time would have been 97.5 days. I round this down to 90 days because over the 18 month period Mr Hemmings clearly had other work to do and I can be confident that at least 90 days would have been applied by him to dealing with the fallout from the steps and seats problems.
144. This produces the following:

Ms Granville - 30 days @ £323.48: £9,704.40

Mr Williams – 30 days @£268.10: £8,043.00

Ms Green – 30 days @ £104.51:£3,135.30

Mr Hemmings - 90 days @ £162.61: £14,634.90

Total: £35,517.60

20. The Museum's Internal Management and staff costs for steps and seats remedial works

145. Ms Granville identifies £90,467 as the likely cost of the Museum's staff time during the remedial works. She says that she, Mr Williams and Mr Hemmings will be deployed for varying percentages of their time during the tender period and the course of the works. This was challenged on the basis both that the assessments of time were excessive and also on the legal basis that it was not recoverable. I have dealt with the legal argument above and I am wholly satisfied that, even if it is necessary to establish it, their time would generate revenue equal to their salaries or that others will have to be paid to fill their normal roles.
146. I have found that the remedial works will take 26 weeks (or 130 working days), all things being equal. Ms Granville identifies a 20 day tendering period. This is obviously a condensed period because, from inception of the scheme and detailed design process, the preparation of drawings and specifications for tender, the sending out of those documents to tenderers, the receipt back of tenders, the consideration of the tenders, the decision making, the acceptance of the successful tender, the finalisation of the construction contract and the start of the work will span probably 6 months at the least. A 20 day tendering period is therefore realistic for her to take.
147. She then takes the whole of the tender period (20 days), 50% of all but the last 2 weeks of the construction phase (60 days) and the whole of the last two weeks (10 days), to produce 90 days in total of her time. She is justifiably anxious to ensure that the problems are resolved and do not happen again and I am satisfied that she will spend substantial periods of time in connection with the remedial works. Neither she nor the Museum can afford to have the problem not resolved or go wrong again. In the tender period she will need to provide input into what is required, to liaise with the professional team, help approve the successful tenderer, liaise with the Museum staff and to involve herself in numerous such activities. The 20 days is a realistic estimate of her time. I suspect however that 70 days over the construction period is somewhat pessimistic given the others, both independent professionals and Museum staff, being involved. In my judgment, 40% of the 130 days is realistic, 52 days.
148. She allows the full time of Mr Williams, the Director of Estates. In my judgment, this is too high, particularly if Mr Hemmings is deployed full time to this project. In effect I wonder what he will be doing all day every day. I can see and accept that he, at his senior level, will need to be involved in detail and for significant periods of his time and will often need to be the first point of contact for others. He will be heavily involved initially in the design and tender stage and regularly and frequently involved as the works progress. I assess that at least 100 days of his time will reasonably be deployed.
149. Mr Hemmings will be deployed full time as the eyes and ears of the Museum and properly and reasonably so during the works. This is justified as providing some additional supervision of not only the works but also of the consultants, liaising with the other functioning parts of the building and to provide effective reporting to the Museum as to what is going on. I would allow his time for 130 days.
150. This quantifies as:

Ms Granville - 72 days @ £323.48: £23,290.56

Mr Williams – 100 days @£268.10: £26,810.00

Mr Hemmings - 130 days @ £162.61: £21,139.30

Total: £71,239.86

Legal costs

151. This is claimed for legal costs associated with having independent solicitors advise on and help with the drafting of the contracts with the remedial works contractor and consultants. This is a reasonable head of claim as it will be important to ensure that the contracts protect the Museum adequately. The sum is obviously reasonable: it amounts to no more than about 40-50 hours of an assistant solicitor which is very modest.

22. Remedial Works Contract/Project/Cost Management

152. The Museum identifies £213,000 as the likely cost for a Project Manager (plus assistant -150 days each), Costs Manager (80 days), Contract Administrator (65 days) and CDMC (10 days) over the period of the lead up to and the execution of the remedial works contract for these steps and seats. Mr Fitch said in evidence that he thought in effect that this was disproportionately high in relation to the likely cost of remedial works and that 15% of the cost of the remedial works themselves was appropriate. His figures and approach were challenged by the defending parties on the basis that they produced too high a figure, particularly in the context of the 15% allowance already in Item 6 (Allowance for design/local authority and building control fees). It was also argued by them that it was totally unnecessary and unreasonable to retain these further consultants.
153. In my judgment, it is wholly reasonable for the Museum to retain consultants to provide project and costs management. I do consider however that the contract administrator role should not be priced separately; the architect often provides this role and is well placed to do so and I consider that the 15% allowance for architect and engineer at which I have already made in relation to Item 6 is sufficient to cover the contract administration role. It is sensible and reasonable for there to be costs management, this almost invariably being provided by quantity surveyors: quantity surveyors are best placed to provide cost reporting prior to the construction contract and cost control and valuation services during the construction project. Project management was always recognised by all parties on this contract as being necessary, reasonable and desirable. There has to be an "interface" between the clients, the consultants and the contractor and it is very important that such project management is provided for the remedial works to provide a reasonable level of assurance to the Museum that everything is being done properly and well by all concerned. There is little issue that some CDM involvement is required; this relates to Construction Design and Management Regulations requirements. The allowance which I have made in item 6 does not include for project and costs management or CDM costs.
154. One therefore turns to the assessment. Mr Fitch said and I accept that the following allowances can and should be made:

Project Manager: 5 days (tender period) and 52 days (contract period)

Project Manager's assistant: 5 days (tender period) and 78 days (contract period)

Costs Manager: 10 days (tender period) and 52 days (contract period).

155. I see no reason not to use the daily cost figures of £600, £250 and £550 upon which this claim is based because they correlate to the figures which were actually charged by Mace and T&T:

Project Manager: 57 days @ £600: £34,200

Project Manager's assistant: 83 days @ £250: £20,750

Costs Manager: 62 days @ £550: £34,100

To this that should be added £2,500 for the CDM requirements. This produces a total of £91,550.

Summary of Damages and Relief in relation to the Steps and Seats

156. In summary, the total monetary damages which I award to the Museum in relation to the steps and seats claim is £1,127,870.40. In addition there will be appropriate declarations in relation to an indemnity against Items 10 and 11.

ITEM	AMOUNT ALLOWED AS DAMAGES
1.Remedial scheme - Basic Cost	£324,780
2. Preliminaries	£94,550
3. Site security	£18,000
Sub-Total	£437,330
4. Allowance for Design Reserve @7½% of the above	£32,799.75
Sub-Total	£470,129.75
5. Allowance for Contingency @8% of the above	£37,610.38
Sub-Total	£507,740.13
6. Allowance for design/local authority and building control fees @ 15% of the above	£76,161.02
Sub-Total	£583,901.15
7. Inflation allowance@2.3% of the above	£13,429.73
Sub-Total	£597,300.88
8. Abortive installation of plinth upstand	£67,936.96
9. Removal of plinth	£12,948.27
10. Security costs	Indemnity
11. Loss and expense incurred by the Contractor in relation to prolongation	Indemnity
12. Survey costs	£6,655
13. Lawrence Bamber	Nil
14. Site hoarding (2011 onwards)	£41,994.25
15. Adana Construction	£1,553.48
16. Adjudicator's fees	£19,830.66
17A. Legal fees in adjudication	£53,000
17B. T&T's time in adjudication	£5,160
18. Professional Fees up to Practical Completion	£113,154
19. The Museum's Internal Management and staff costs to practical completion	£35,517.60
20. The Museum's Internal Management and staff costs for steps and seats remedial works	£71,239.86
21. Legal costs	£10,000
22.Remedial Works Contract Project and Cost Management	£91,550
TOTAL	£1,127,870.40

Contribution

157. It is necessary to analyse the above figures to determine what loss has been (or will be) caused by the Contractor's breaches of contract. I take out Items 8 and 9 which are entirely the responsibility and fault of AEW. Items 16, 17A and 17B on analysis have nothing to do with the Contractor and stem only from AEW's defaults. Similarly, Items 18 and 19 were not caused as such by any breach on the part of the Contractor. That leaves the balance, which is all was as much caused by the breaches of contract of the Contract. The balance is £820,323.60.
158. The Contractor is liable under its contract for negligence in relation to its failure to specify adequate cover in relation to reinforcement for the steps and seats but not for any carelessness in proposing a gap of 10 mm between units. It is not liable for the geometry problems.
159. Section 1(1) of the Serve all Liability (Contribution) Act 1978 states that:

"…any person liable in respect of any damage suffered by another person may recover contribution from any other person liable in respect of the same damage (whether jointly with him or otherwise)".

Section 2(1) of that Act states:

"…the amount of the contribution recoverable from any person shall be such as may be found by the court to be just and equitable having regard to the extent of that person's responsibility for the damage in question."

160. I have formed the view that the Contractor should bear responsibility for 25% of what might be called the common damage. My reasons are as follows:

(a) The responsibility for the inadequate concrete cover rests (in broad terms) equally between AEW and the Contractor. The responsibility for fixing cover was the Contractor's because it was part of its contractually assumed Designed Portion. However, AEW are equally to blame for failing to specify in the specifications what the criteria were or should be. It was the Contractor (or its sub-contractor for whom it was contractually responsible) which selected the 25 mm cover allowance and put it up for approval. It was AEW which negligently caused, allowed or permitted that allowance to be or to stand as approved.

(b) However, AEW is wholly responsible for the geometry problems and for the excessive gap allowance of 10 mm.

(c) If the only problem had been the gaps, wholesale replacement would not have been required and there would simply have had to have been substantial raising and refitting of the units. If the only problem had been the gaps and the geometry, it is likely that a significant number of units could have been re-used.

(d) The full remedial scheme would, largely, have been required by reason of the reinforcement cover problem because all the units would have to have been completely replaced to overcome that problem. However, on that assumption, the design would otherwise have been a tried and tested one which would have involved less design work and therefore cost.

(e) It is difficult in many cases, including this one, to adopt some mathematical method of fixing a just and equitable percentage to reflect responsibility of two separate parties. 25% reflects the above factors in circumstances where overall the primary responsibility rests with the architects in relation to whom there was a substantial abnegation of responsibility and continuing carelessness and the secondary responsibility rests with the Contractor which put forward carelessly and without any discernible forethought an inadequate precast concrete specification. I do not seek to underestimate the fault or responsibility of the Contractor but in the overall scheme of events in this case their responsibility overall was not insignificantly less than that of AEW.

There will therefore be a liability on the part of the Contractor to make contribution to AEW in the sum of 25% of £820,323.60, namely £205,080.90.

Decision

161. There will be judgment for the Museum against AEW for the sum of £1,127,870.40 in relation to the steps, seats and terraces plus an indemnity in relation it Item 10 above (Security costs) and Item 11 (Loss and expense incurred by the Contractor in relation to prolongation). All questions of interest will addressed separately and later. There will be judgment for AEW on the Part 20 proceedings in the sum of £205,080.90. Due to time constraints caused by my (I hope justifiable) reluctance to start substantive work on the judgment whilst the parties were apparently trying to settle the proceedings following final speeches, I will continue to complete the judgment overall in relation to the ceilings claims which I will hope to produce over the next few weeks.