Design Awards: 2003

City of Manchester Stadium, Manchester

City of Manchester Stadium, Manchester

Architect

Arup Associates

Structural Engineer

Arup Associates and Arup

Steelwork Contractor

Watson Steel Structures Ltd

Main Contractor

Laing O’Rourke Ltd

Client

Manchester City Council

Manchester has a new iconic symbol for the city. It was completed in March 2002 as the centrepiece of the hugely successful XVII Commonwealth Games. The stadium was constructed on a derelict site and will act as a catalyst for the redevelopment of the surrounding area.

The Stadium structure utilises a mixture of structural systems. In-situ and precast concrete were used to construct the stadium bowl and structural steel supported from a cable-net of masts and steel cables to form the roof.

The City of Manchester Stadium is a remarkable structure due to several key features:

  • It is one of the most cost effective quality stadia of its size in Europe. Typical examples of multi-function components of the building are:
    • The stadium is circular to provide optimum views for spectators. It sweeps up from low sides on the North and South elevations that allow sun on to the grassed area, to high sides on the East and West giving protection from prevailing winds and low sun angles.
    • Roof Structural Liner Tray – these 150 deep aluminium panels act structurally to support the roof sheeting as well as creating a hidden zone for acoustic insulation, wiring and roof bracing. The trays also form a visually clean ceiling to the roof that would not usually be economically viable on aesthetic grounds alone.Concrete Ramp Towers – the eight concrete towers to the east and west of the stadium serve three distinct purposes. Firstly they support the spiral ramps that provide access and egress for spectators. Secondly the spaces within the concrete ramp drums are utilised for plant as well as toilet facilities. Finally they provide an elevated support for eight of the 12 roof masts.
  • The stadium is unique in Europe as a building of two distinct lives – initially a 41,000 seat athletics stadium and then to be permanently converted into a 48,000 seat football stadium (completion Summer 2003). The construction flexibility is central to the success of this transformation. The primary roof support structure that consists of a pre-stressed mast and cable-net system is independent of the roof-plane rafters and purlins. This allowed the roof to be added below the cable-net in whatever sequence was required.

The innovative mast and cable-net roof primary structure utilises a ‘grounded tension ring’ in order to create a prestress field against uplift wind loads. The structure comprises 12 cigar-shaped tubular steel masts up to 65 metres high. Eight of the masts sit on cone shaped tubular supports on top of the spiral concrete ramps at the East and West sides. The masts support 76 spiral strand forestay cables in fan-shaped groups of five or seven cables per mast. Each forestay supports an individual roof rafter. Just above the roof surface all forestay ends are connected by a system of four spiral strand cables that form the grounded tension ring (also referred to as the ‘catenary’). Prestress to the catenary and cable-net is provided by the four corner-ties anchored to the ground. The top of each column is tied back to the ground by pairs of backstays comprising groups of ‘Macalloy’ high tensile steel rods.

The erection scheme provided the greatest challenge for the team. The rafters, masts and pyramid supports were fabricated in transportable sections and then welded at site into complete elements. After carrying out risk assessments on the erection scheme it was decided to construct the rafters on temporary props generally supported on the concrete terrace. This allowed the construction of other elements to proceed at the same time without the constraints of sequence. If the masts and cables had been erected first, to provide support for rafters, any delay to the critical cable assembly would have a corresponding delay to the remaining work.

The catenary cables were assembled at ground level in the bowl of the stadium, on jigs which supported the nodes in the correct geometry. After clamping the four cables at the node points, the complete assembly was lifted on top of the rafters and supported on temporary works.

In conjunction with the above, masts were erected and made stable by the permanent backstays and temporary forestays connected to the temporary props supporting the rafters. At this stage the masts were positioned one degree forward of their pre-set geometry to facilitate fixing the permanent forestay cables.

The corner ties to the completed catenary were erected, connected to the catenary, and a pre-tension of 200KN applied. The permanent forestays from mast to catenary were fixed using a predetermined sequence that ensured the catenary displacements were within acceptable limits.

The final tensioning of the cable net could now commence – the basic sequence being to increase the corner tie tension to 1000KN simultaneously at each corner using temporary hollow jacks on the ends of the cables. This was followed by releasing the temporary forestays whilst at the same time adjusting the permanent backstays to maintain a minimum tension. When the majority of the load had transferred from the temporary forestays into the catenary the forestays were then released. Once all the forestays were released final tensioning commenced. Firstly all the backstays to the masts were jacked to length, all four pairs simultaneously, and the pins inserted into the anchorages. After all the backstays were complete the final tensioning of the corner ties commenced simultaneously increasing the tension to 2550kn. The final activity was to jack up the rafters from their supports install its linking member to the catenary node and remove the props.

In summary the structural solution for the stadium has produced a design that not only adds significantly to the overall stadium architecture but is one of the best value-for-money stadia of its size in Europe. It is a demonstration of overall building design, which can be attributed as much to the engineering and construction as to the architect.

Judges’ Comment

s:

The memorable “Mexican wave” roof is suspended from beautifully engineered tension masts, which themselves grow out of the distinctive circular ramp access routes. A catenary ring cable holds the roof down and this is incrementally readjusted to accommodate the fourth side of the stadium now being constructed.

Overall the impression is of an integrated and ingenious building where the design and construction of the steel work is central to the entire project.

New Hangars for TAG Farnborough Airport, Farnborough

New Hangers for TAG Farnborough Airport, Farnborough

Architect

REID Architecture

Structural Engineer

Buro Happold

Steelwork Contractor

Rowecord Engineering Ltd

Main Contractor

Bovis Lend Lease

Client

TAG Farnborough Airport Ltd

Part of the £45m redevelopment of TAG Farnborough Airport, which also includes a 35m high air traffic control tower and brand new terminal, the £9m three bay hangar is 290m long, 45m deep and 22m high at the apex and large enough to accommodate six Boeing 737s.

TAG Farnborough has a vision for the airport and seeks to differentiate themselves from other service providers in this field through the design and quality of the facilities it provides. The challenge set for the design and construction team of Reid Architecture, Buro Happold and Bovis Lend Lease was to accommodate the functional requirements with a design aesthetic that reflects the qualities of the TAG brand image and yet without a cost premium over the more conventional design and build ‘shoe box’ hangars.

The design team appreciated that they had to adopt a radical ‘back to first principles’ approach to meet this challenge and develop a design that was ultra efficient. As with most buildings, a very significant component of cost is the cladding – it was essential to reduce the area of the elevations as much as possible. The added benefit of reducing the volume of the building and minimising the clad elevations is improved aesthetics, reduced wind load on the structure and a reduced impact on the surroundings.

Various structural systems were explored with the arch proving to be the most efficient. The arch followed the natural profile of the plane geometry, ie maximum headroom where the tail fin is and reduced at the wing tips. From a structural point of view an arch is a very efficient structural system acting largely in pure compression minimising bending and deflection. Traditionally the arch reactions are resisted by either using thrust blocks, which would have been large and expensive, or by installing a tie between the arch ends. More usually in a tied arch of this type the tie is placed above the minimum level of the plane increasing the overall height of the building. To avoid raising the structure, the arch form was extended to ground level through the use of inclined “A” frames in the form of concrete filled tubes. In this way the tie could be placed underground in the form of prestressed reinforced concrete beam. By introducing roller doors in tail fin slots in the gable end of the hangar the elevation could be reduced further. Fit out of accommodation within the hangar envelope can then take place with offices and workshop accommodation located around the support legs, rather than in ‘bolt on’ accommodation at the back or sides of the hangar as is more normally the case.

A key concern in the design was the bending induced in the arch through asymmetric loading. Bending resistance was introduced by forming the arch from a trussed arch 3m deep formed from rectangular hollow section chords and square hollow section lacing. The trusses are spaced 9m and span 90m. Secondary trusses link the trusses together and reduce the buckling length of the chords. Each of the trusses is connected to “A” framed support via a pin. The “A” framed legs are made up of concrete filled circular hollow section legs and a headpiece fabricated from 80mm steel plate. Two wind trusses spanning 90m achieve lateral stability. To gain a detailed understanding of how the structure is behaving it was modelled as a three-dimensional non-linear model.

By working closely with the steelwork contractor an erection procedure was established which proved both simple, cost effective and reliable. Each 90m truss was split into three segments. A double bay was assembled on the ground comprising two truss segments linked with all connecting secondary trusses and purlins. These segments would then be lifted in place and jointed in the air. After an initial learning curve and some refinements this method proved very successful. The hangar steel was erected on programme.

The hangar construction commenced with ground works in October/November 2001. Steelwork erection started January/February 2002. The main hangar was completed in November/December 2002 with additional office space being added until April 2003. A total of 823t of structural steel (63 kg/m2) and approximately 100t of cold rolled steel was used in this hangar.

This project has been a good example of what can be achieved by close co-operation between the client, the design team and the specialist contractors and how creative design can achieve a result that completely satisfies the client’s aspirations at a cost of no more than conventional solutions and yet lifts the spirits and is a positive addition to our built environment.

Judges’ Comment

s:

A fundamentally simple concept that meets all the taxing demands of a fast-moving industry has generated a clear solution that is elegant in its design, rational in its engineering technology and economic in its means of implementation. This hangar now sets the standards to which others must aspire. TAG’s design and construction team has produced a winner!

Millennium Point, Birmingham

Millennium Point, Birmingham

Architect

Nicholas Grimshaw & Partners

Engineers

Bur Happold

Main Contractor

Galliford Midlands

Client

Millennium Point Property Ltd

Sustainability and the care of our natural environment are increasingly important considerations of the construction industry and ones that are now affecting the choice of materials, building systems and the management of construction. The design of Millennium Point attempts to address one of the more environmentally significant aspects of the industry. It does this by reducing the need for wasteful demolition and rebuilding whilst meeting the changing needs of occupiers and new technology.

The structural system developed for this building offers the fit out and servicing advantages of traditional flat slabs. However, in addition, it greatly enhances the longevity of the structure by adding the ability for the form of the floors to be changed, without costly and intrusive strengthening or demolition works.

Millennium Point is an example of an enormous building, designed to be truly flexible and adaptable, as well as durable and quick to build.

Millennium Point, the millennial landmark project for the Midlands, opened to the public on 29 September 2001. The development covers a site the size of six international soccer pitches, and is the catalyst for the regeneration of the east side of Birmingham city centre.

From the start of the project, an essential aspect of the brief to the design team was to create a high quality modern building: one that expressed the engineering heritage of the region, and where the structural and mechanical functions are clearly expressed. This was a deliberate intention, in order to allow the building itself to be perceived as part of the exhibition of, and investigation into, technology.

The different requirements of the component facilities within Millennium Point led to the design of a truly flexible, adaptable building, a building that allowed for the creative museology of Thinktank, and the changing needs of exhibition, retail and education facilities.

Working together, the design team developed a solution that will allow creative accommodation for any number of different uses in the years to come. An expressed composite steel frame supports reinforced concrete floor slabs that were cast on a pre-cast concrete permanent formwork system. The supply air, electrical and IT cabling are distributed within a deep raised floor and the lighting and air extraction systems are suspended from the exposed structural slab soffits. This holistic approach, expressing the structure and building services as part of the architecture, maximised repetition in the implementation of the building elements, allowing the structure to be prefabricated and assembled quickly, almost as a kit of parts, on site. The exposed integrated design solution allows both the construction and the working of the building to be easily understood by visitors: effectively the building itself has become part of the educational experience of Millennium Point.

Apart from being an integral part of the building’s architectural and environmental strategy, the structural frame was designed not only to be adaptable, but also to be both durable and fast to build. It was quickly realised that a form of flat slab construction would best suit the many and varied uses planned to meet the vision for the building, and that flat slab construction would also allow the unhindered transverse distribution of services. However, a problem soon arose as detail design proved that a conventional reinforced concrete flat slab structure would become uneconomically heavy if it was placed on a 9m grid. This form of construction also posed problems with the quality control of the exposed slab soffits. Furthermore due to the heavy level of reinforcement, which would be required, particularly around the columns, only minor openings could be cut into the concrete slabs to allow for the installation of future services and building alterations. This conventional solution would have severely impeded the desired flexible nature of the internal structure.

To overcome these disadvantages, whilst retaining the advantages of the flat soffit and overall shallow structural depth, a composite structural steel and reinforced concrete hybrid frame was developed. This hybrid structure basically concentrates the reinforcement into discrete lines of structural steel, spanning between the columns and a cross head of structural steel, bringing the floor loads into the columns. While the bottom flanges of the steelwork are exposed, expressing the grid pattern of the floor structure in the slab soffit, the beams are embedded within the concrete slabs, dealing effectively with the appropriate fire rating requirements. The floor beams are set out on a standard 3m by 6m grid in both directions, with 3m square cross head details connecting the grid to the columns. The system allows considerable flexibility in the configuration of the building. Any of the concrete slab sections that fill in between the steel beams can be removed, as can the triangular pieces around the columns to allow space for service risers. The 3m by 6m strips between the columns provide the capability to accommodate any future need for the installation of stairs, allowing 1.5m for each flight and a 1.5m deep landing at each end. Most dramatically, the central 6m by 6m soffit section between the steel columns can be removed, to provide a double height space for specific exhibitions or equipment.

Furthermore, the exposed bottom flanges of the beams offer a regular pattern of fixing points from which to suspend displays or exhibits, without damaging the aesthetic of the finished precast concrete slabs.

Continuing the theme of integral fire rating, the columns are constructed from composite structural steel that has been filled with reinforced concrete. Designed in accordance with Eurocode 4 part 2, the slender columns, with a 457mm diameter, achieve the fire rating required while eliminating the costly and time-consuming application of any additional fire protection. The columns came to the Millennium Point site fully primed, only needing top coats of paint to be applied on site. This fast track approach has produced a durable column finish that is both easy and cost effective to apply and maintain.

The various sections of Millennium Point’s frame were prefabricated off site, and then delivered and erected systematically alongside the installation of the precast concrete. Once the frame was lined and levelled the concrete topping was put in place.

The design of the structural steel frame gave specific focus to ensuring the maximum use of prefabricated components. All of the elements that make up the structural steel frame – columns, cross heads and beams – were carefully designed so that they could be manufactured into distinct modular sections with simple bolted connections to ensure rapid, easy assembly on site. The concrete filling of the columns and floor topping work compositely with the steelwork and finally lock the different sections of the frame together. This approach, together with the introduction of the precast concrete floor, ensured a very high quality building, while also enabling a very quick erection process on site. Logistically, the design approach allowed the construction of the frame to advance well ahead of the following trades, minimising the disruption of a congested busy building site.

Judges’ Comment

s:

Composite columns, shear-heads and flat slab construction all together provide an innovative combination of engineering solutions in structural steelwork. The achievement is exactly what it says in the brief, “a kit of parts, where the structural and mechanical functions are clearly expressed, and is truly flexible and adaptable.”

Brighton Dome and Museum, Brighton

Brighton Dome and Museum, Brighton

Architect

The Arts team at RHWL

Structural Engineer

Whitby Bird & Partners

Steelwork Contractor

Bourne Steel Ltd

Main Contractor

Skanska UK Building Ltd

Client

Brighton Dome and Museum Development Co Ltd

The 200-year old Brighton Dome, Corn Exchange and Museum buildings are a combination of a unique historical heritage and styles of world importance. They were in need of renewal to sustain their continuing existence.

The buildings were originally commissioned in 1803 by George, Prince of Wales, later the Prince Regent as riding stables and a riding house. They have undergone many changes since then.

The original Dome, which, at 80ft diameter x 65ft high, was the largest timber-framed structure of its type in the world. The Dome was originally supported on a timber ring beam consisting of three wooden sections that circled the building and supported the main Dome Roof, this beam was in turn supported by a series of cast iron supports.

From 1863 until 1930 the Dome was used as Assembly Rooms. The Corn Exchange together with the Museum and Art Gallery were added in 1873. The Pavilion Theatre, seating over 2,000, was formed in the 1930s with the dome auditorium transformed by the addition of an Art Deco ceiling supported by steel trusses beneath the existing timber-framed Dome.

This then, was the first use of structural steelwork on this project. It was used in 1930 to sustain and modernise the building that had originally been constructed in 1803. Now, over 70 years later, steelwork has again been chosen to further extend the life of the buildings.

Part of the project involved the removal of the two proscenium columns added in the 1930s to replace the previous cast iron supports which were replaced by cantilevered beams inserted into the roof space. This involved steel-framed temporary works to support the existing timber Dome and 1930s trusses, then transferring the loads by jacking onto the new steel frame. All of the temporary steelwork and the new permanent steelwork had to be manhandled into the existing buildings and then erected from inside. It was a very difficult and congested site.

This work was successfully completed whilst maintaining the relative level of the existing domed roof structure. No measurable settlement or uplift occurred. Various areas of the refurbishment site are listed as Grade 1 and 2 status meaning that the works had to be carried out with sensitivity to the condition and nature of the existing structures.

Pre-loading of elements and jacking of existing structures were used to prevent excessive deflections. Substantial alterations, such as forming openings in walls, were dealt with by maintaining existing load paths and by spreading stress concentrations through box frames or spreader beams to ensure that the overall load distribution was not significantly altered.

Parts of the existing steelwork that had been dismantled, together with some of the new temporary support steelwork, were re-fabricated and incorporated into the new permanent works. In effect, the steelwork was re-used or re-cycled.

Approximately 500 tonnes of temporary and permanent structural steelwork was installed over a 22 month period between April 2000 and February 2002.

Judges’ Comment

25 Gresham Street, London

25 Gresham Street, London

Architect

Nicholas Grimshaw & Partners

Structural Engineer

Whitby Bird & Partners

Structural Contractor

Rowen Structures Ltd

Main Contractor

Exterior International plc

Client

Asticus (UK) Ltd

25 Gresham Street is a 120,000 sq ft headquarters building providing 10 floors of column free office space. Developed by IVG Asticus Real Estate Ltd and now occupied by Lloyds TSB, it is situated on an island site in the City of London.

The site straddles the remains of a Roman fort and, in locations where foundation piles would otherwise have coincided with an archaeological deposit, the load paths were transferred using steel A-frames within the basement level.

The structure is designed as a braced frame with simply supported floor beams spanning between columns. Fabricated steel sections with an integrated service zone achieved 12m clear spans from the building perimeter to the core. The central braced core provides lateral stability for transverse wind loads and the suspended south elevation. Vertical braced bays in the east and west stair cores provide additional resistance to torsion and out of balance loading on the hangers. Diaphragm action of the floor plates transmits lateral wind load from the perimeter cladding to the core.

The key architectural concept focuses on the relationship with the adjacent garden, originally the St John Zachary Churchyard. Accommodation is organised around an open sided south facing atrium overlooking the garden. The atrium contains the principal vertical circulation, four glass lifts reached from a series of glass floored bridge decks and the scheme extends the garden with terraced planting beds climbing up the external face of the atrium. The imaginative use of structural steel enables the southern edge of the floors to be hung, thus avoiding any ground floor columns along the garden boundary. Steel vertical braced bays around the central service core resist the overturning moments induced by the inclined hangers. Plan bracing transfers the resultant push/pull horizontal forces at first and ninth floors from the hanger node points to the central core.

The diagonal tensile rod ties that provide support for the principal structure were assessed in a detailed fire-engineering analysis to ascertain what effect an internal fire would have on the stability of the structure. The initial assessment was based on the ratio of energy input from the fire to the mass of the hanger available to absorb the energy. To determine the performance of the hanger more accurately, assessors calculated the temperature of the environment to which a tension rod was likely to be exposed in a fire. Taking account of the thermal properties of the steel, the temperature of the fire and the duration of exposure, it was possible to calculate the peak temperature achieved by the hanger.

Temporary props supporting the first floor enabled the simultaneous construction of the suspended south bays with the main frame up to the hanger connection nodes at the ninth floor. Hydraulic jacks lifting the hangers transferred the load from the temporary props to the inclined hangers. Tension to the hangers was applied progressively, in pairs to control distortion sway on the structure. The measured movements were continually checked against the predicted theoretical values, determined from the detailed analysis of the frame and the tolerance allowances of the cladding assembly.

Judges’ Comment

s:

This imaginative multi-storey steel framework has admirably accommodated the architecture, sunken garden and Roman archaeology in this City of London site. The attention that has been given to the relationship of this building with its external environment is clear to see, and very well done.

Hampden Gurney School, London

Hampden Gurney School, London

Architects

Building Design Partnership

Structural Engineer

Building Design Partnership

Structural Contractor

Premier Structures Ltd

Main Contractor

Jarvis Construction Ltd

Client

Hampden Gurney School

BDP has broken the mould of inner city education buildings with Hampden Gurney School. In contrast to the single-storey schools often found in the densest parts of our cities, BDP has designed a multi-level primary school that creates the corner piece of a Marylebone city block in London.

The project includes two new six-storey apartment blocks on each side, the profits from which funded the redevelopment of the school.

Classrooms are set on three levels above ground floor and there is a technology teaching room on the roof. Children “move up” the school from nursery level at the ground floor. Play decks, located at each level of teaching, are separated from the classrooms by bridges across the central atrium. The decks provide safe, weatherproof play for different age groups adjacent to their classrooms as well as the prospect of open-air classrooms on warm days. The hall, chapel and music and drama room are set at the lower ground level.

The structural concept responds to two key aspects of the Client’s brief – the need for a flexible space for sports, dining and worship at lower ground level and strict programme constraints linked to term times and phased transfer.

The steel framed structure has an innovative roof truss that suspends the centre of the building to create the 16m clear span at lower ground level – the truss picks up the loads by means of Macalloy steel hangers connected to each floor at mid-span. Only when one enters the basement does the structural concept become apparent. The column free area creates a flexible space at lower ground level offering a host of possibilities for play, worship and performance. The steel bow arch is visible on the roof – a lightweight tensile PTFE canopy springs from the truss, protecting the atrium below and creating a sheltered and inspirational space for environmental learning and experimentation.

BDP designed the structure for simple and fast construction – the entire steel frame was erected on temporary columns. Macalloy hangers were then installed and tensioned, transferring load from the temporary columns into the roof truss. The structure was simply lifted off the temporary compression columns when the load transfer was complete, allowing easy removal of the temporary columns.

Sustainability was considered throughout the design process. BDP ‘designed in’ demountablilty of the structure – steel columns could be inserted in the hanger positions and, after load take up, the building could be demounted in a traditional way. Also, the play areas are open to the fresh air and the long side of each is curved to the south to enjoy all day sun. The central atrium provides cross ventilation to the naturally ventilated classrooms.

The construction budget for the school was £6m. The structural frame comprised 200 tonnes of steelwork and the average cost of the primary frame was £1,000 per tonne and of the arch £2,000 per tonne.

Judges’ Comment

s:

This novel structure pioneers the way to optimise the use of land set aside for educational purposes in inner city conurbations by adopting the concept of the vertical primary school. Steel and composite construction are used efficiently and effectively to provide a large column-free space at ground level for sport, assembly and other collective activities, whilst the upper floors, suspended from the bow arch and at roof level, accommodate teaching facilities for each of the class groups as they progress upwards to the completion of their primary education.

Kinnaird House, 1-2 Pall Mall East, London

Kinnaird House, 1-2 Pall Mall East, London

Architect

Trehearne Architects

Structural Engineer

WSP Cantor Seinuk

Structural Contractor

Bourne Steel Ltd

Main Contractor

Kier Build Ltd

Client

Haslemere Estates Management Ltd and Schildvink bv

Kinnaird House was constructed in the early 1920s on an island site. It was built using Portland stone held in place by an integral steel frame.

Steel and stone were tied together with mortar, brick and concrete with rubble fill in places. The original floors were constructed using riveted steel plated beams with concrete and hollow clay pots and a floating timber floor.

The client’s main criterion for the redevelopment was that the existing character of the building should be maintained while maximising the net lettable floor area. This was achieved by retaining all four facades and reconstructing the internal floors. Careful investigation proved that the existing perimeter stanchions and foundations could remain unaltered. Re-using the majority of the original foundations also produced a design that did not affect the Bakerloo Line running tunnels that cross directly below one corner of the building.

Several studies were undertaken in the initial stages of the project to determine the position of the core and the number of columns within the building. With careful planning and optimising of the beam spans and services locations it proved possible to reduce the total number of internal columns to just four, giving the client excellent floor space. The adoption of a slimflor beam system and lightweight concrete metal deck floor slabs and the consequent reduction in load carried by the foundations enabled an additional floor to be inserted into the old banking hall area and an extra floor to be added for plant at roof level.

New angle brackets were welded to the existing stanchions during the demolition phase to assist in the erection of the steelwork frame. This simple procedure greatly assisted the following main-frame erection process and contributed to safe and efficient work on site.

Where appropriate, re-cycled materials were specified. In effect, the original embedded steelwork was re-cycled by its re-use in the new load-carrying frame. Trehearne Architects’ proposal was based on a design that would provide an environmentally friendly building with maximum net lettable area and fully integrated mechanical and electrical services. By carefully selecting the level of the first floor steelwork it was possible to use the existing full height ground floor windows to naturally light ground and first floor without affecting the external facade.

The newly refurbished building achieved an ‘excellent’ rating under the Building Research Establishment Environmental Assessment Method (BREEAM). This is uncommon for a refurbished air-conditioned building in central London.

The key features of the building are the use of simple slimflor beam construction and lightweight concrete on metal decking floor slabs and the connection of the new internal steelwork frame to the original embedded steelwork stanchions. The use of the slimflor construction solution also allowed an unhindered services zone across each floor plate. Steelwork framing for the turrets, chimneys and vehicle entrance also shows that steelwork is a versatile material that can be used to deal with complicated geometry.

Judges’ Comment

s:

Kinnaird House represents a fine solution to the problems of inner city reconstructions, occupying a prominent site near London’s Trafalgar Square. The challenge of inserting new floors, with one additional storey, within the retained facades is a familiar one. The success in coping with the logistical problems of sequencing deliveries, new framing and reconstruction could only be achieved by the skilful use of steelwork.

Eric Hollies Stand, Warwickshire County Cricket Club

Eric Hollies Stand, Warwickshire County Cricket Club

Architect

Bryant Priest Newman

Structural Engineer

Price & Myers

Structural Contractor

L B Structures Ltd

Main Contractor

Interserve Project Services Ltd

Client

Warwickshire County Council

Bryant Priest Newman Architects were appointed to act as designers for the redevelopment of the Eric Hollies Stand in 2000.

Following the success of the Edgbaston Indoor Cricket Centre project, Price and Myers Structural Engineers and Graves Quantity Surveyors were also appointed by WCCC Development Manager, Philip Macdonald to work on the project within the guidelines set out in the master plan for the ground produced by Lob HOK.

The brief was to replace an existing terrace/embankment with a new stand increasing capacity by 1,300 and providing improved facilities and viewing for able bodied and disabled spectators. The design was developed using similar materials and principles carried out in other projects at Edgbaston by Bryant Priest Newman, to provide a consistent aesthetic.

WCCC also required the redeveloped stand to be covered by a canopy. This is effectively a giant ‘sun shade’ to protect spectators from the worst excesses of the sun during the long hours of play of our ‘Summer Game’. The concept for these elements was to provide simple flat, thin planes that conceal the simple structure above. Bryant Priest Newman wanted to create a series of roof planes that appear to hover above the crowd almost unsupported.

The articulation of the roofs into eight separate parasols (two per structural bay) allows the advertising boards, which were a requirement of WCCC, to be positioned away from the leading edge of each roof plane expressing the thinness and allowing the effects of wind uplift to be dramatically reduced. The advertising boards are set in line with the roof ties and follow the same geometry which signifies the split between front and rear roof.

The four solid bays are linked together with lightweight stairs and louvres that indicate the change in geometry. This repetition is carried through to the underside of the stand where each bay is expressed and linked with the brick panels below. The lightweight cladding and the simple repetition ensured that the structural elements could be kept to a minimum using standard sections in an innovative way making the stand very economical.

The England and Wales Cricket Board advise Cricket Clubs/grounds to budget for around £1,000 per seat for new stands. The Eric Hollies Stand, however, equates to around £350 per seat.

Judges’ Comment

s:

The imaginative use of steel in this new stand provides an economical, functional yet elegant solution to the problem of providing extra capacity as well as improved facilities and viewing for able-bodied and disabled spectators at this famous sporting venue.