Krankenhaus Kada: Hospitals are buildings for all, but they rarely offer proper public spaces. Here is a hierarchy of spatial experience ranging from the semi-private ward to the public domain.

If the economic and efficiency arguments for building hospitals in a rational modernist way persist, and if this means keeping largely to rectangular forms, regular column grids, and repetitive fields of cladding, Klaus Kada demonstrates that the result need not be oppressive. He won the competition against such talents as Volker Giencke mainly for his site strategy, which resolves contextual relations with a few deft strokes. The site was on the edge of town, a downhill east-facing slope next to the old hospital building which now has another use. Kada placed the bulk of his hospital at right-angles to the old building, corner to corner, creating a shared outdoor space and borrowing its drive for ambulance access and services. His new north wing is a two-storey tract of treatment facilities and operating theatres. Behind this -- with a dividing gap -- lie a couple of ward blocks set parallel and in line, but with a void between them. This void is occupied by a glazed hall, the highest element of the complex and its social centre. It looks out towards the south, away from the town to a country view.

Kada's master-stroke was to add a third ward wing projecting from the south side and skewed 62 degrees from principal orientation. This angle was borrowed from the road bordering the site to east, and Kada further exploited it in low terraces both to north and south. These platforms resolve the fall in the landscape, allowing expansion of service rooms at basement level. Ward wings project dramatically beyond them on pilotis to both south and east. The most important effect of the skew in angle is the raised plateau of entrance court created in the eastern corner. Spatially continuous with the glazed hall through the great window, the court is visually central to the whole complex, and on the outside it feels protected. The good view beyond is preserved for, instead of surrounding the building with tarmac and drowning it in a sea of cars like most hospitals, the land to the south-east and south-west is a garden, luxuriantly planted with trees and shrubs. The visitor's car park is demoted to the eastern corner across the road: a low and unobtrusive place. Lift and stair are provided, leading to the curved walkway above, which bridges the road then traverses the garden to the building. A further lift and ramp allow direct access from a closer car drop-off at the bridge's end.

One can imagine tut-tutting about the changes of level and difficulties of access for the elderly and wheelchair bound: for many architects the knee-jerk reaction would have been simply to avoid the whole apparatus, yet access problems are solved, the road is crossed, and the great bridge provides the most dramatic and memorable entry sequence of any hospital I have ever visited. You arrive in the triangular court and are funnelled towards the entrance, with glimpses into the great glass hall beyond. Slip through the doors and another drama unfolds. The four-storey hall towers up, daylit to the south when blinds are open, and side-lit to the north at upper levels too. Main circulation consists of bridge links at upper levels, connected to stair and lift. The latter is glazed, so unusually in a modern hospital your sense of vertical location is preserved rather than anaesthetized. The three levels also identify themselves by offering different experiences. Middle floors lead through straightforwardly to the t hree ward wings, but the top floor reveals the underside of the roof, ending to the east with a terrace where patients can sit out.

The ground floor is the most complex. Next to the entrance is the receptionists' booth, treated as building within a building. Ambulant patients attending clinics are invited to wait in the open area beyond -- the central space between the two building tracts. Just a storey high with a glass roof, this area is more intimate than the tall part of the hall. Towards the west end is the main staircase, its bottom flight skewed to the angle of the south wing in response to the diagonal thrust of the approach. Further over, but still within the hall space, is the cafeteria. Here visitors wait and convalescent patients meet, but it also conveys a more general suggestion of hospitality. It has an outdoor terrace to the west. Continuing the social theme, the ground floor end of the south wing -- otherwise mainly administration -- contains a small chapel, unobtrusive yet centrally placed and easily reached. It is differentiated from the general fabric of the wing by double doors and a projecting side bay, while the se ating, altar and raked floor orientate it just south of east.

Behind the hall to the north is the zone of medical intervention, with operating theatres, recovery rooms, X-ray and other diagnostic facilities. Kada accepted the disciplines of sterility and medical procedure, creating the usual labyrinth of corridors and thresholds. Surprisingly though, he managed to allow the operating theatres daylight, letting doctors and nurses see out to surrounding mountains. Fragile glass seems to threaten the sterile environment, but with today's glazing and sealing methods and the provision of positive pressure ventilation, there is no reason to suppose it less safe. For people confined all day, view and daylight are as desirable as for those in less taxing occupations. As it faces north, there is no problem with sun.

Patient wards are largely on first and second floors, with a third level on the west wing only. Mostly there are four beds to a room, with some twins. Patient rooms face south and west, enjoying the best views to garden and sun, while nurses' stations and services are across the corridor to the north. Solar gain is restricted by automatic sunblinds on the southern facades, which completely change the building's appearance. Corridors have end windows, and also gain daylight from the side via clerestoreys, while the top floor corridor has a full rooflight. Although the column and slab construction system is regular and efficient, Kada was able to ring the changes with room arrangements, so each wing is subtly different from the next, and their ends also vary.

Detailing, as usual with Kada, is crucial for the ethos of the building. The steel structure of the hall seems daringly slender, with thinnest possible supports for the glazing and most delicate tie bars for roof trusses. The layering of the facades incorporates sunblinds almost like kinetic sculpture: no compromise of add-on here. And as with Kada's earlier buildings, elements are carefully juxtaposed, with deliberate gaps to allow them integrity. Two examples should suffice. Many architects would have run the south wing straight into the body of the building rather than just connecting it with a glazed link. The chosen arrangement leaves a tantalizingly unnecessary external corner space, but it avoids collision details and all such repercussions, and it allows Kada more of his beloved bridges. The second example is the waiting area on the ground floor. Set in a gap between the hall and the treatment wing, it is treated like a courtyard internalized, with its own glass roof. Not only does this maintain the structural integrity of hall and wing: it also creates a transitional space for a transitional function.

The building has heavy servicing provision with large basement areas for plant rooms and underground ducts for tempering incoming air - an increasingly familiar practice. But Kada does not overemphasize servicing. And he manages to underplay the elaborate fire precautions that must be in place, and whose demands often kill spatial continuity in buildings of this kind. Each ward wing has its own emergency stairs and the hall can presumably therefore be regarded as sacrificial, but one gets no sense of heavy compartmentation while walking around.

In general character, Hartberg recalls early Modernist hospitals and sanatoria, with an optimistic feeling of light and air and a promise of brisk efficiency. The kind of architecture Jan Duiker tried to make at Zonnestraal is shown 70 years later to be realizable without leaks and without excessive heat loss and gain. But the greatest triumph lies surely in the hospital's spatial coherence and strong sense of place: it shows that despite all rules, regulations and technical limitations, a modern hospital need not be a technical monster or a disorientating labyrinth. After Kada had won the competition and was developing the design, there was a call to cut out the extravagant' hall - those square metres apparently undedicated to any particular medical purpose. Fortunately the design had already gone too far and this philistine move was successfully resisted, for without the hall as its heart and centre, is not the building quite unthinkable?