… but how did they actually make them?
The four meeting-room pods, which seem to float in the glass pavilion like fish in a tank, make up the most spectacular, even outrageous, elements of Queen Mary’s medical research building. They are pure Will Alsop, having been conceived in one of his exuberant paintings. They are also one of the most technically challenging elements of the building, as all four pods, named Centre of the Cell, Spiky, Cloud and Mushroom, were deliberately designed to be as different from each other as possible.
They were let as specialist design-and-build packages on lump-sum subcontracts to the main JCT contract. However, problems arose early on when two specialist trade contractors that had started working up detailed designs on a fee basis, Cowley Timber Structures and Robb TM, went into receivership – though fortunately before contracts were agreed. Contracts were then switched to Architen Landrell for Spiky and Centre of the Cell, and Design & Display for Cloud and Mushroom. Westbury Tubular Structures installed the steel supports as part of the main structural steel contract. The three totally enclosed pods have displacement ventilation supplied and, with the exception of Centre of the Cell, extracted through floor voids.
Simon Carter, the project architect, says that, as the two specialist contractors were in their element in constructing the pods and were given three months to work up detailed design with Alsop, the whole fabrication and assembly went smoothly. “This was partly because the components were fabricated to fine tolerances, although these proved tricky for Westbury on the steelwork,” he says. “But when it came to installing the components on site, they all fitted together with very little making good.”
Centre of the Cell
This cluster of orange bubbles is the real star of the four pods. Its shiny orange shell encloses a double-decker visitor centre for 30 people with a floor area of 195 m2. It is also the only pod with a representational form – it was inspired by the nucleus of a cell.
Being the largest pod, it required the most complex structural and services arrangements. It is propped off the surrounding pavilion structure by six tubular steel legs. And its outer shell is supported on four vertical steel hoops braced by the two steel floor decks. Air is exhausted through the roof by means of 12 curly exhaust tubes, which are eerily reminiscent of umbilical cords.
The shell was cast in the form of 90 fibreglass panels by Design & Display. “The real challenge for us was making the moulds for the Y-shaped sections between the hemispherical bubbles,” says design manager, Dick Kiss. “In the end, we built up a carcass of one-fifth of the whole envelope but without the bubbles. We then split that up to make the Y-shaped sections. It was a long, expensive process.”
The moulds were built to the required shape in simple joinery carcassing and polyester filler, and then buffed up to a fine gloss finish. The glass fibre castings then emerged fully finished and were fixed on site by bolting them together through inward-projecting flanges. The end product is a marvel of finesse, with no visible steps, buckles, gaps or scuffs on or between the glossy, curvy panels.
The most outlandish of the four pods is Spiky, which looks like a giant deep sea creature with 12 sharply pointed arms flailing in all directions. Underneath its jet-black skin its basic structure comprises a steel deck propped by raking tubular steel legs off the main pavilion structure.
When it came to forming the 12 dominant spikes out of the elastic PVCu skin, two opposing techniques were used. Eight of the spikes are pulled out by cables as in a conventional tensile structure. But the other four spikes are pushed out by rigid steel telescopic arms braced against the steel deck. As both the cables and the telescopic arms are all but invisible, the spikes appear to exist of their own free will.
After an elaborate computer patterning exercise, Spiky’s skin was made in a single piece by Architen Landrell and delivered in a 1.5 m3 crate. “There was only one rip during fitting,” says Carter. “In the end, it was finally stretched taught using a giant zip. This runs up one of the spikes and was concealed behind a fabric flap.”
Cloud involved the most complex construction of the four pods, according to Carter. This was despite it having the least complicated geometry, being basically an elliptical airship enclosed in fabric. The complexity was caused by the 43 dB of sound insulation required to reduce noise transmission between its two meeting rooms. The solution was to line the pod, except for portholes at either end, in mineral-wool acoustic insulation behind oak-faced mdf panels.
Cloud is built around a steel deck supported on four splayed tubular steel legs. The external envelope is wrapped around elliptical steel hoops, with the longitudinal stability provided by internal mdf panels. The mdf lining was supplied in flat triangular patterns designed to fit together in a geodesic pattern to cope with the pod’s double curvature.
Timber battens were fixed to the outside of the steel hoops, and slight irregularities were packed out in thin layers of mdf. Then the tensile PVCu fabric was stretched to a scalloped profile and stapled to the battens. Finally, a cosmetic aluminium cover strip was stapled to the battens. Things did not always go according to plan. The fabric envelope was damaged by the building works going on around it and had to be replaced.
Mushroom differs from the other three pods in that it takes the form of an open-topped boat. It is also located a floor lower than its neighbours, which has meant that, instead of being supported by the surrounding superstructure of the glass pavilion, Mushroom is supported on three vertical concrete columns rising up from their own piled foundations. A steel helical stairway wraps itself around the columns, giving access from the basement.
The boat itself has a steel frame, and its side wall undulate in height from 1.2 m to 4 m. It is lined on the inside in grp panels, which were left with a rough finish as the floor and walls are covered in carpet. The black and white panels on the outside, by contrast, were cast by specialist Gillespie in glass-reinforced gypsum. As in plasterboard drylining, the joints between the grg panels were taped and skimmed on site. This was the only wet trade involved.
To Dick Kiss, design manager of Design & Display, the biggest challenge was installing the inconspicuous strips that run along the wavy top and bottom of the perimeter wall. “Each strip snakes up and down, twists and varies in width. So we had to cut 6 mm layers of MDF board on site, and then bend it and build it up to the required outline. It was laborious but the only way to do it.”
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