Behnisch in Ohringen.

This school, like the one in Frankfurt, is near a motorway and has adopted protective tactics to establish territory and presence.

Ohringen is a small town near Heilbronn, an Autobahn-hour or so north of Stuttgart. The new school is not a secondary school like that in Frankfurt, but a Kaufmannische Schule, providing specialised education in business studies and economics for teenagers, like our former technical colleges. It was again the outcome of an architectural competition, and again the site strategy is the leading idea.

The site lies on the edge of the town in the valley of the river Ohrn next to an elevated section of the Heilbronn-Nuremberg motorway. Although this must once have been a pretty rural spot, it has suffered the usual kind of edge-city sporadic development. On one side stand dull rows of suburban pitched roof houses, on the other, the typically incoherent mixture of drive-in commercial premises - motor dealerships, garden centres, furniture warehouses and the like - that tend to spring up between towns and motorway intersections, each with its selfish utilitarian logic and loud declamatory style. The space for the new school could scarcely have been more generous, but it immediately invoked the responsibility that the school should make some visual impact. The building needed not just to take possession of its own site, but to provide a landmark, to generate some coherence in the neighbourhood.

This was the main reason for the great ring raised on stilts. It gives the appearance of a very large building, yet is incomplete and encloses a large area of site space. It traverses a ground level change of about one floor, which is carefully manipulated - as often in late Behnisch buildings - to reduce the apparent scale of the complex on the north side, and to bring the landscape into its heart. As with the first radial Behnisch school at Oppelsbohm, the extroverted classrooms get slightly different views and orientations, while the introverted corridors bring pupils together as a community in the central space. However, with the enormous radius at Ohringen they only see each other across this space. To meet, they must walk around the inner passage to a triangular hall by the main entrance, within the south side of the ring. This hall, enclosing the main staircase, is both foyer and place of assembly. Fully glazed onto the inner circle, it remains part of the general space embraced by the ring. Its sloping roof defers to the higher form of the ring, running down towards the centre. It is treated as an added sheltering element, not a positive built solid.

As with the earlier radial schools, the ring contains two floors of normal classrooms, while other parts are given more specialised articulation. At ground level on the east side is a series of rooms built between the columns of the ring and given irregular perimeters to show their non-conformity. These are threshold elements like the porter's office and the pupils' library and cafeteria - food signifies hospitality. Beyond the triangular hall on the first floor, and running out to meet the hill, are administration and staff common room. Close to the centre of activities, they also have a commanding view.

The tongue of elevated land which runs from the north into the space embraced by the school is flanked by two further elements: on the north-east, half buried, a group of science rooms; on the north-west the gymnasium. This is by far the largest and highest room, yet it is not allowed to become externally overbearing. Its corner picks up the edge of the implied circle, and its orientation is almost north-south. As at Frankfurt, entry is at the upper level, allowing spectators to see the whole space at a glance and to find their seats quickly and easily. But unlike Frankfurt, it was unnecessary to bury the bulk of the hall, which is visible at its full scale from the west, with windows to ground level. Manipulation of the site levels allows the whole building to be buried on the east side, which reduces its apparent bulk as well as permitting the seemingly effortless high-level entry. This treatment recalls various earlier Behnisch sports halls, and Ohringen can be seen as a refined replay of an architectural vocabulary which has accumulated over many years.(1) The roof is also a new variation on an earlier theme. It appears flat at first, but viewed in relation to the horizontal inner wall at the north end, it turns out to be pitched, rising from east to west, draining rainwater at the entry end and making its climax over the great west window. Upstanding laminated beams take the east-west span, allowing north-facing glazing to descend from the head of each beam to the roof plane. The rooflights taper as at Frankfurt, again admitting more light to the less generously glazed side.

An established vocabulary

Both new Behnisch schools are impressively finished and detailed showing confident use of a vocabulary elaborated over decades. Everything is light and graceful, with lots of glass, the narrowest possible sections, and subsidiary elements such as structural bracing and sunblinds applied as secondary layers which become ornamental in the sense of Pugin's second principle.(2) The juxtapositions and collisions of the various building-bodies are nicely judged, ends well made and corners cleverly turned. Elaborate games are played in section with the ground plane, reducing bulk where it might become unfortunate, developing outside paths, and tying building to landscape. Both schools give a pleasantly light and airy impression, with delicate structures and soaring roofs. They repay careful study of detail. Many of the interesting contrasts developed between the planes and surfaces of the various building elements reflect the order of construction, making decorative sense of the progress from first to second fix and on to finishes.

As a sample let us consider the outer facade of the great ring at Ohringen. As a horizontal flat-roofed body repetitively glazed it could so easily be heavy and banal, yet it is a wonderful shimmering sight in the sunlight, and so full of telling details. The projecting upper sun visor caps the building from a distance like a roof, yet is impossibly thin. Seen from closer, it hides the real roof and the thickness of its construction. The lower sun-visor is smaller, yet doubles as an escape balcony, and so carries a light handrail. Both layers of glazing have delicate mullions and show the rhythm of their vents and opening lights, while venetian blinds drop horizontally in front when the sun is too intense. To make them feel less exposed and to allow space for radiators, the glazing stops at knee level in the classrooms. On the outside this part is clad in a thin impermeable sheet, breaking the vertical rhythm of the mullions, and adding colour which changes from lemon to lime to violet. These horizontal bands of cladding are broken at intervals, however, to allow a window at the front of a classroom down to the floor, and thus the rhythm of the classroom layout is expressed. On the ground floor are exposed concrete columns setting another rhythm; and the envelope, where present, is retracted. It is a rich, interesting facade, but the visual effects derive from the tasks which it has to fulfil: solar protection, the spatial transition from inside to out, and also from the way it is put together. It has its own visual richness, and needs no applied iconography. Only colour. Colour has been an increasing concern of the Behnisch office in recent years and has become both prominent and daring in their buildings. Behnisch has written: 'By adding colour, I try to overcome the pre-ordained world. The world in question is not only the world of appearances. Often, I want to overcome a world dominated by certain forces, eg of production, marketing, administration systems. These systems urge me to use products that are cheap and clever and perhaps also durable. But I dislike them. I want to keep my distance from them. And I do not want the objects of this world to be visible around me. They are welcome as invisible assistants - as assistants who, wherever they appear in my image of the world, have to wear beautiful garments, like courtiers had to in the past... More attention should be given to colour. It costs little; it is unfettered and effective. It has to be borne in mind that the visual impact of buildings or architectural contexts will not be complete or complex if it is considered from this context alone. But it is nonetheless worthwhile'.(3)

For the last decade Behnisch and his team have been experimenting with colour in an increasingly bold manner. They generally leave it until late in the building process, experimenting on the finished building until they get it right. Much at Frankfurt, including the cool blue interiors, the warmer tones in the gym, and the alternating yellow and white blinds seems successful and inspiring, but the motorway wall in blue and yellow is not quite convincing, and the architects are not satisfied that they developed it far enough. The external colours at Ohringen are more compelling, while the internal ones come as quite a surprise. As the building came together, the architects thought they had a serious visual problem with the long and repetitive passages, which turned out less gallery-like than they had hoped. This was surely a symptom of the main weakness of the plan that so large a ring contains too much space and dissipates energy instead of focusing it. So worried were they about the repetitive effect in the passages that they called in an artist, Erich Wiesner, who set up his studio in the building and devised a scheme. By painting the doors and panels in a series of very bright colours he completely mitigated the unwanted effect. Behnisch commented generously: 'We found, not for the first time, that while introducing "outsiders" is somewhat disturbing, they also enrich our work, forcing us out of our rut'.(4)

1 For the developing story of the Behnisch sports halls from around 1969 see AR February 1991, pp63-72.

2 '...that all ornament should consist of enrichment of the essential construction of the building'. A.W.N. Pugin True Principles of Christian or Pointed Architecture, 1853, first page.

3 Behnisch, in the booklet On Colour. published by Gerd Hatje, 1993.

4 Statement issued by the Behnisch office dated October 1994.