Foster and Partners' Faculty of Management at Robert Gordon University, Aberdeen, unites nature and academe with an over-arching steel roof
All cities have their own sets of extremes, but Aberdeen's sound especially exotic. It has the brashness of an oil town, but two universities with foundations which date back centuries; and it offers qualities of life with dangerous employment opportunities, with urban life surrounded by some of the most unforgiving natural environments in the uk. London may also be a city of extremes, but these are different; sheltering from a shower on the North Downs is not like digging a snow hole in the Cairngorms. Baku and Bergen may share the possibility of ski-ing in the morning and working on an oil rig in the afternoon, but neither has a university management faculty designed by Foster and Partners.
Apart from wanting 'a step change' from the scattered and fragmented previous home, 'we were seriously underprovided in the late 1980s and early 1990s', says dean Bill McIntosh. 'We had no preconceptions about the shape'. The faculty sees itself as an 'innovative, enterprising environment, and Foster's fitted that bill', he says of the commission which was awarded after 'a fairly lengthy selection process'.
This faculty is the largest of the four in the Robert Gordon University, the younger of Aberdeen's pair, yet still dating from 1731 when the Baltic trader Robert Gordon left his fortune to establish an educational institute. McIntosh says it has about 2500 students (on a combination of full-time, part-time, evening and sandwich courses) studying in the faculty's three schools, the Aberdeen Business School, the School of Information and Media, and Public Administration and Law. When the institute of technology was upgraded to university status in 1992, it spread across numerous sites in the city. Its vice-principal, coincidentally an architect, decided to consolidate on one site, a strip of land off the Garthdee Road. Another entrepreneurial benefactor, Scott Sutherland, has his name attached to the school of design which has long been located there.
It's a site with a small, local ambiguity which recalls some of the larger ones of the city itself. Falling quite steeply from the road to the River Dee, it is both suburban and rural, almost wild as several herds of deer graze on it. Dixon Jones, when it designed a couple of nice halls of residence a few years ago, responded to this by adopting a traditional, Scottish rural form, the circular tower, from which most rooms take advantage of the spectacular views to the south and west. But the Faculty of Management is a more public building, and straddles a new route which the university masterplan has created to connect its existing, new and projected facilities. Running below, and more or less parallel to, the road, this is intended to relieve traffic and form a spine which literally and metaphorically unites the university.
So, Foster's building has three specific conditions. To the south the land slopes away towards the river; to the north are suburbia, a faculty car park, the road and houses above; while to the east and west lie, or will lie, parts of the campus. Put that together with constraints on height set by the tree line and restrictions on building too close to the trees on the perimeter, and the form adopted seems, as so often with Foster, the only possible solution. Certainly the huge, oversailing curved roof makes a covering for a great deal of accommodation, 15,000m2 in total, without any part having to exceed the 15m limit above natural ground level. 'We looked at a series of stepped terraces,' says Foster associate and project architect Lulie Fisher, 'but that would have been expensive.' The curve is an efficient way of covering the volume, and steel was the only feasible material.
It is also what makes the building special. At the lower, southern end, the great steel curved roof members rise straight out of the ground - 'an important visual effect,' confirms Fisher - in keeping with the wild and elemental character of the site. This is where the snow will fall to, although bars on the roof prevent it from forming a heavy avalanche which would bring the gutter off with it. Here, too, in the summer, students, staff and guests can gather to catch evening sun and admire the view. Even in winter a cluster of common rooms and communal spaces, including a 'wintergarden', indicate this possibility. At the northern end the roof rests on a wall partially clad in local granite, the city's most distinctive local building material. This lends an appropriately urban flavour to the car park and approach.
Internally the roof form also brings many benefits. Where the spinal route enters the building, it becomes an atrium. With a couple of cafes, easy access to the library and lecture theatres, and overlooked by staff offices, informal meeting areas and seminar rooms, it exudes a more explicitly urban character inside than out. It is also a possible venue for public and revenue-generating events, in addition to its deliberate function, reinforced by meeting areas on first-floor galleries, of encouraging interaction between staff and students. The route into the library forms an important cross axis, symbolically and directly tying the building into the landscape, academe to nature. The roof form allows for a series of skylights which reflect direct sun off curved panels down into the heart of the space which would otherwise be deep and dependent on artificial light. Skylights also make the library attractive and well-lit.
The roof is the dominant factor in determining the building's aesthetic: its shape and form depend entirely on an effect which can only be practically achieved in steel. As Fisher says: 'Having steel on top gives a lightness and the possibility of quite dramatic shapes . . . that's the beauty of it'. Fosters pushed the engineer, Ove Arup and Partners, hard to get the circular steel columns as slender as possible. It was also possible to eliminate intermediate columns, so the roof rests on supports which form a 9 x 12 m grid, reinforcing the perception that the roof hovers over the building. So slender are the columns that at some distance they might almost be tie rods.
Considerable effort has been put into developing a suitably elegant steel detail which eliminates the problem of cold bridging. At the southern end of the building the curved steel roof beams project externally, and here Fosters has avoided the potential of cold bridging by forming a 'break' in the beam's continuity at the junction of the external wall. At this point the two parts of the beam section are bolted together, only separated by an insulated spacer piece. The two outermost curved members are completely external and bring structural expression to the exterior.
A similar potential concern arose where the steel roof members breached the compartment wall between the atrium and the library. Here, a 90-minute fire rating was required which may have been compromised by steel's propensity to conduct heat from one side of the compartment to the other. So at this junction, a similar discontinuity in the steel roof members, as outlined above, has been introduced with a 25mm gap between each section, filled with a non-combustible packing piece.
To eliminate the possibility of radiative heat transfer across the compartment boundary, the steel members have an intumescent coating applied along a short length of the beams on each side of the wall. This is the only point where intumescent paint to the exposed steelwork was required.
The roof structure originated as standard 12m-long universal beams, cross section 533 by 210mm, supplied by British Steel. Bob Souter, the project engineer at Ove Arup and Partners' Aberdeen office, explains that at 82kg/m, each beam weighed about a tonne, so did not need special arrangements for site delivery.
Fabrication, however, was another matter. The beams had to be curved to a 200m radius by Angle Ring, a company based in the Midlands which specialises in bending steel beams. But, following a policy set by the university governors to use as many local materials and contractors as possible, the fabricator which added the plates and the joints, and delivered and erected the steel was a local firm, Gilcomston Construction. It was a task, remembers Gilcomston's Bob Mackay, that went beyond its normal fare of portal frames and sheds. 'It was a prestige job,' he says, 'and we thought, 'we've got the software, why not do it',' adding a reference to the Strucad software which made the setting out of the fabrication very much simpler. 'I wouldn't have fancied doing it by hand,' he admits. He recalls that there were hardly any on-site faults, despite the complexity of making joints which have to be vertical on a piece of steel which is curved.
Arup's, however, 'prepared the fabrication drawings in the traditional fashion,' remembers Souter. 'Basic stick drawings showing the layout.' At the time, 'we didn't have the software . . . it can be done now,' and he acknowledges that programs like Strucad make life much easier for the fabricator.
Dean McIntosh is understandably proud of the faculty's and university's connection to the community. Robert Gordon's bequest was tied to the local area and especially those with the surname Gordon. A good 50 per cent of the students come from the Highland and Grampian region, and a strong connection with oil, the dominant local industry, is mutually beneficial.
'Greater Aberdeen, if there is such as thing,' he says, 'has a population of about 250,000, and 40,000 jobs are related to oil and gas'. The Business School has many specialisms which serve it, such as stress management and offshore installation, everything to do with maintenance, supply and management of the rigs. This pays off in an employment record 'in the top three across universities in the uk', and the ability to attract Ian Wood, founder of oil service company the Wood Group, chair of Scottish Enterprise (and 'Mr Scotland' adds McIntosh) to open the building.
It is these ambitions which Foster's design aims to reinforce: 'the pictures being drawn [by the architects] tied up with our wishes and self image'. It's always dangerous to read buildings too literally, but an overarching steel roof tying city to nature, and the academy to the community, seems appropriate.