Specifier's choice:National Waterfront Museum, Swansea, south Wales
Just to the west of Wilkinson Eyre's spectacular Port Tawe north bridge is the newly named Swansea Maritime Quarter. Part of it is a set of old docks lined with warehouses, one of which - a Grade II-listed brick structure - had been converted into the Swansea Maritime and Industrial Museum.
This building, now linked to a spectacular new structure by Wilkinson Eyre immediately to its north, is soon to be the National Waterfront Museum. The old warehouse sits four-square along the dock. The new structure takes the form of four overlapping and distorted rectangles - actually they are rhomboids, whose curving track follows the curve of the old railway tracks - as does the new landscape structure. Wilkinson Eyre associate Martin Knight explains: 'The curves follow the powerful geometry of the railway lines from the industrial age.
The reason for the docks being there was the success of Welsh industry, and the docks were connected to it by the railway lines.
This combination produced a strong form, a generator, and something we wanted the new building to follow. In the landscape we are expressing the line of the tracks literally using 50mm-wide kerbs set out following the original railway lines and with different types of planting between them.' You think, a bit, of French landscape designer Bernard Lassus and his notion of the jardin des retours (garden of returns). Afan Landscapes is the landscape contractor.
The new building has a steel frame and the four overlapping roofs are flat. The south facade is clad in slate and the north in curtain walling, providing the galleries behind with big, even light. The old warehouse/ museum building is a long, wide two-storey structure with a pitched roof and a small extension at the western end. One bay in from this end is a big diagonal connection that ploughs through the new structure, across the gap and out the other side of the old. The stepping-plan profile of the new part is an architectural device because inside it is one big space with a curving mezzanine (also following the line of the old railway) running the length of the south side - with a gap in the second smallest rhomboid where the connection runs through. Each of the rhomboids has its own vertical services core.
The old building has exhibition space on the eastern side of its first floor, with the ground floor given over to commercial lets, an auditorium and administration offices.
Assembling the teams The client wanted, pace Graham Morrison, a 'signature building' that would 'put Swansea on the map'. Wilkinson Eyre won the contract on the basis of a convincing competitive interview. The client brought together the consultant team: project manager and quantity surveyor Davis Langdon was already on board and the M&E consultant, McCann & Partners, and structural engineer, Arup, tendered separately. Knight explains: 'The exhibition designer [Land Design Studio] was appointed soon after us and we were invited to participate in its selection. It was a good thing and allowed us to work together, so the design and the exhibition are closely linked.' Originally, the architect's contract was based on a Scope of Works contract from SCA 92. Knight says: 'During the process of appointing consultants it was decided to use the New Engineering Contract (NEC) form for everyone instead of a series of bespoke professional services contacts. The main contract was a JCT 98 (private with quantities), which incorporates sectional completion and contractors' design portion supplements, and was procured on a two-stage basis.' The sectional-completion provisions covered a lot of the car parking, completed during the first stage, which has now been handed back before the project is complete for use by the city of Swansea.
Staging post The first stage of this two-stage contract was for enabling works, with structural steelwork, the slate cladding and the glazed curtain walling to form part of this. This was based on fairly advanced drawings - post Stage E but, as Knight explains, not detail drawings. With Mowlem Building (South Wales) appointed for the enabling works, the newly appointed contractor actively helped the design team to develop the detail design and the tender packages in light of the agreed contract sum. The quantity surveyor required 80 per cent cost certainty before going on to the next stage - and that was achieved by this close development work with the main contractor. Had the cost certainty target not been reached, the second stage would have been up for retendering.
For the second stage there is a set of rolling packages, which are tendered as and when the main contractor wishes to procure them. 'This was not a formal partnering agreement but the process of rolling negotiation does allow for something like it, ' Knight says. 'And the Mowlem people have been very proactive throughout the process. The team we had working with us was unusually young and was used to working on design-and-build jobs. That has given then a positive mindset and they are keen.
I think there are very positive things about this process; the negative side is that you probably design things several times over and, as you get closer to the end, the possibility of fine-tuning is lessened. Still, here it was reasonably successful.' Real-world specifying Wilkinson Eyre was anxious to avoid performance specifications and, of the 55 sections in the specification, only four are performance-based. The rest are split fairly evenly between architect-generated specification and specification based on contractor design. The basic rule seems to have been that performance specification was acceptable where the element was out of sight. Where there was a specialist element plus a visual content, this would go to contractor design - because the contractor knew the limitations, when the architect could not be expected to.
Knight says: 'There are always going to be areas where the expertise of the architect is limited. It makes commercial and programmatical sense to make use of the specialists.
It's making best use of what's available.' But the specification has to be handled sensitively. Knight says: 'If we had been less specific [about naming manufacturers], other manufacturers would have been offered up because they would have met the criteria. If we had gone too far and designed packages to the nth degree, we would have put off the specialists because they would have had no scope to refine the design using their own skills.
So our drawings [and specification] show our design intent. We work closely with the subcontractors as the design is developed and also after they have won the contract.' Listing and sustainability Knight says: 'We didn't use NBS, rather the Davis Langdon Schumann Smith specification whose writing we outsourced to Schumann Smith. We outsource when it's appropriate.
This was a mix of old and new building.
Knight says: 'One of the complexities is we are dealing with a Grade II-listed building, which was in poor condition. Achieving reasonable environmental conditions has been quite a challenge. And the balance between high internal specification and overall sustainability has had to be quite carefully developed. We are using a number of bespoke systems for the building but the main new galleries use an underfloor heating system to reduce the amount of air that is pumped around and gives more stable conditions. There is a dock-water cooling system and we are making quite a lot of use of rainwater harvesting. There are also solar collector panels, which are used to preheat circulating water and which will, I'm assured in this, the wettest city in Wales, work.' Meshing IT For computer-assisted design (CAD) operations, Wilkinson Eyre runs on MicroStation.
Structural engineer Arup uses AutoCAD and the Gloucestershire steel fabricator, Billington Structures, runs StruCad from Acecad, an interactive three-dimensional solid-modelling system for steel buildings that can generate drawings, fabrication details and CNC (compuer numerical control) data.
Knight says: 'We are all impressed with the way Billington Structures did the steelwork.
There were a couple of the guys from here and from Arup [and Billington] who all worked very closely together to produce a three-dimensional StruCad model using the structural line drawing of the engineer and the details of the structural characteristics of the members. You can click on a member and develop its physical properties. It's really quite an impressive tool.
'What they did was to physically model every structural member and then analyse the connections, the nodes and methods of assembly. This became CAM (computer-assisted manufacture) information and, rather than us laboriously checking all of the steel drawings afterwards, all the checking was done over the shoulder of the Billington CAD operator, who was an absolute genius.
The process of checking was reduced from several weeks to a matter of days. There was no loss of quality because the engineers who have generated the structural design, which is terribly complex, the architect looking at the whole envelope and the fabricator are all three working around one model. So the error rate for checking and coordination was reduced enormously. At the end, we agreed it, they pressed a button, and it started coming out at the other end at the factory. There were real programme benefits, and Billington was outstanding.' Covering up There was a laudable wish to use indigenous materials, and Welsh slate was an obvious choice for a building given over to the history of Welsh industry. Knight says: 'I don't know if you have been in a slate quarry but the riven face of slate is stunning - it's quite different from slate [as you see it on roofs]. So we have tried to create a riven face with horizontal banding evocative of the quarried material.
We used three different colours of slate from two different quarries: one a heather red;
another a heather blue; and then a dark blue grey. The differences are quite subtle and depend on the light.' The chosen pieces of slate were each given a pair of dowels in the back and were laid face-down in a big mould, 10m long by about 3m high at Trent Concrete's works. Concrete was poured in and the resulting panel weighed about 10 tonnes.
Knight says: 'The lovely thing about this is that these precise panels were simply bolted back to the steel and, straight after the steel frame was finished, we had an almost completed elevation. Having things face-down in a mould, you worry desperately about quality control, but Trent Concrete did it well. It built a beautiful sample and was very good.' For the curtain walling, Knight explains:
'We were looking at the market for a manufacturer that was of the right size, was prepared to do the work and was interested.
There were a number of different systems we could have gone with including Kawneer, but Sch³co fitted the bill - using approved fabricator Parry Bowen, which also installed the point-fixed glazing.' The roof is a single-ply membrane originally specified as Sarnafil but which the main contractor persuaded the architect could be substituted with FatraFoil from Fatra (UK). Eaves soffits are Eternit board.
The louvres around roof-plant units and in a band running round the skirt of the slate cladding were specified as Kingfisher Louvre Systems products. The company's louvres are thin and elegant.
The project is scheduled to complete later this year and work has already started on the interiors.