ADIA is the headquarters for the Abu Dhabi Investment Authority, located in Abu Dhabi. Some 73,000m 2of office space is arranged in curved wings either side of a core and atrium which tapers toward the top as the number of lifts reduces. This atrium is part of a stack-effect extract ventilation system and also houses sky gardens.
The workload of KPF's London office, established in Covent Garden in 1990, has been remarkably varied. One of its early successes was in the competition for a new Cypriot parliament in Nicosia (there is some hope that this might now be built). It has completed a major university building in Oxford and is working on schemes for St Anne's College, Oxford, and the LSE. Relatively modest 'urban repair' projects have engaged its attentions.
The commercial office sector, however, remains as fundamental to the work of the London studio as it is to KPF's global operation - the practice was founded in New York in 1976 and first came to critical attention with 333 Wacker Drive, Chicago, one of the best post-war buildings in the city.
For Lee Polisano and David Leventhal, the American-born principals who were responsible for establishing the London office, getting to grips with the office culture of Europe was a priority from the start.
(London was always the base for a Europewide operation. KPF's London team is nearly 110 strong and now includes just seven Americans. ) The buildings which KPF did at Canary Wharf were essentially imports, designed from New York. They addressed the needs of post-'Big Bang' London but could not have been built in Germany or Holland. American architecture, however, provided a source-book for the process of rethinking the office and moving beyond the universal models of the International Style.
Wright's Larkin Building, Saarinen's John Deere Headquarters and Roche Dinkeloo's Ford Foundation are among the seminal projects to which Polisano and Leventhal turned for inspiration. These were all bespoke buildings and KPF's experience is the same as other architects - corporate clients innovate, speculative developers are far more cautious. 'Although someone like Gerald Ronson [the client for KPF's Heron Tower] maybe breaks the mould, ' says Polisano. ) Canary Wharf, Broadgate and other big 1980s and '90s developments, tailored to the needs of the global financial sector, reflected Britain's pursuit of a US model in which big floorplates were linked to sealed facades and energy-intensive servicing. As the Heron Tower (110 Bishopsgate) project confirms, however, there is an office market in London beyond that for dealing floors and large headquarters buildings. In northern Europe, attitudes rather greener than those prevalent in Britain, were reflected in more stringent regulations relating to energy use and access to daylight. In Germany, in particular, the preference for cellular offices remains strong. The tall office building, the defining feature of most US cities, was, and remains, a contentious issue everywhere, including London.
Thames Court, located close to Southwark Bridge in the City and completed in 1998, reflected the restrictions imposed on office development in Europe's financial capital. It forms the backdrop to a number of subsequent KPF projects across Europe in terms of workplace design, environmental strategy and urban response, and is particularly interesting as a building where a reconciliation is attempted between the office cultures of Europe and North America.
The complications of building anything on the site (listed buildings, archaeology, the St Paul's Heights code and the proximity of both the river and an urban motorway) were enormous, so that the innovative moves achieved in the project come as something ofa surprise. Given a pre-let to an investment bank, the client stipulated a flexible mix of spaces including a dealing floor and open-plan and cellular offices.
From the reception area, which forms a buffer zone to mediate traffic noise, to the toplit second floor atrium, the building contains a remarkable variety of spaces. The use of extensive shading, opening windows and natural ventilation, using fresh air drawn in from the river at basement level, constituted an energy programme that, certainly by London standards, was highly progressive.
These ideas were developed further in the original KBB project in Dusseldorf. (After a change of client, the scheme has since been substantially redesigned. ) As Polisano comments: 'We fattened up the typical German office building.' Unusually wide floors were possible because workspaces, mostly cellular, were arranged along external edges, with meeting rooms and other communal spaces in the central zones. Planned for multiple accommodation as a 'doughnut' occupying a regular city block, the building focused on a central court covered by a glazed roof, the latter designed to act as a lung, with fresh air drawn in at the basement and exhausted through opening roof vents. Offices would have opening windows onto this temperate public space, with double-skin glazed facades on street elevations to exclude traffic noise and fumes.
The idea of a communal - where possible, public - space as both the spatial and social focus of an office development and an environmental generator, is a perennial KPF preoccupation. It emerges in a project which, superficially at least, seems cast in a global mould. The 73,000m (ADIA) draws on several earlier KPF highrise projects in which wings of offices flanked central atria.
Abu Dhabi is oil-rich but the ADIA building, due to be completed in 2004, is no gas-guzzler. The double-glazed facades, wrapping around office floors and atrium, are part of an environmental programme for ventilation and cooling devised in collaboration with Buro Happold. The central atrium is not just a dazzling space - it also acts as a thermal chimney for the extraction of stale air. The office spaces are a mix of cellular and open plan, with central zones for meetings and interaction that look into the atrium with its series of sky gardens. The views both within the building and out to sea are spectacular.
The climate of Madrid in high summer is hardly more temperate than that of the Gulf - temperatures frequently climb into the 40infinityCs. The recently completed headquarters building for ENDESA is located on the edge of the Spanish capital, close to the M40 orbital motorway on what was, until recently, a bleak sierra. ENDESA is a major power utility with offices and service centres scattered around Madrid and now concentrated in the new 80,000m 2building.
The company wanted the new headquarters to be a practical demonstration of good environmental practice as well as a place that encouraged interactive working and facilitated the use of new office technology.
The offices are arranged in two irregular, 18m-deep wings, connected by bridges, flanking a huge, two-level atrium. The latter is both the entrance to the offices and a public space, open to all, with shops, restaurants and a health club, a generous gesture in a new commercial quarter which lacks such facilities.
Atrium and office wings sit under a vast 8,000m 2roof, a 'fifth elevation', structurally spectacular and - like the projected roof at KBB - the 'lung' of the building. The servicing strategy, developed by Battle McCarthy, is based on detailed analysis of the local climate. Fresh, chilled air - the sierra nights can be chilly - is drawn in through underground ducts to ventilate the atrium. The double skin of the roof, with a glazed 3,000m 2covering to the atrium itself and a system of fixed louvres to provide solar shading, acts as a thermal chimney, the heat of the sun drawing out stale air. Offices have opening windows to the atrium - external windows are sealed - and are cooled by a fan-coil displacement system rather than the conventional air conditioning generally favoured in new Spanish office developments. ENDESA reflects strongly the KPF quest for the office building as community. In the alarming sprawl of outer Madrid, it stands as a marker for civic and urban values.
A big roof again features in KPF's first building at River City in Prague. The site for River City is an area formerly occupied by industry and rail yards, east of the historic city centre, on the banks of the River Vltava.
The development (seven buildings are planned, four of them by KPF) is a reflection of Prague's arrival on the world business scene, and is unashamedly aimed at international finance, with German and Austrian banks in the lead. For some it is bound to seem an alien intrusion, yet its generous planning has a civic dimension which extends beyond purely commercial considerations. Building One, recently completed, with 25,000m 2of offices plus a small retail element, is a marker for the whole development, occupying a wedge-shaped plot at the western extremity of the site and presenting a sharp prow to the street. The building is essentially a speculative scheme, designed for multiple occupation by the financial sector, but it breaks the normal rules of spec office developments. Office floors, typically 18m spans and containing a high proportion of cellular space in the German tradition, are arranged in an L-shaped configuration on the northern (river) side and eastern edges of the building.
Along the south side, where the development abuts an extremely busy dual carriageway, a glazed, full-height atrium forms an environmental buffer to the road.
(A similar tactic is being pursued in KPF's forthcoming Paddington Central scheme, where the context is the even busier M40. ) Engineered with Battle McCarthy and RFR Paris, the atrium is a lightweight, lowenergy space; its glazed double-skin wall incorporating connecting walkways and providing a plenum which is part of the natural ventilation strategy for the space. The roof sits on a forest of slender, tapering columns. Typically, the service cores in a spec office building of this sort would be pushed to the edge. Here the lift banks are placed centrally in the atrium, animating the space and encouraging the chance interaction which (it is now widely believed) is the essence of dynamic business. It is no accident that Karen Cook, the KPF partner who has led the River City project, was the key player at KBB. Many of the themes of the latter have re-emerged in Prague.
The Heron Tower at 110 Bishopsgate is undoubtedly the KPF project which has received most publicity, at least in Britain.
Government approval for its construction, given last year, was welcome news in the City, providing hope that the degree of reconstruction needed to equip the City for a developing office economy might be possible.
The irony was that the tower replaces existing buildings, drab and cheaply built, which exemplify everything that is worst about the post-1945 development of the City, so that English Heritage's opposition to the project seemed all the more inexplicable.
Nor is it within the area covered by the St Paul's Heights code. Moreover, the scheme provides for the creation of a new square, formed by closing off an existing street, which gives the Georgian church of St Botolph a much enhanced setting.
The public gains provided are clear but the rationale of the project is, of course, essentially commercial. Developer Gerald Ronson identified the market for highquality, highly serviced office space accommodating small- to medium-size firms, often international in their operations, who need to be close to the heart of the City. The revamped NatWest Tower (now Tower 42) addressed the same market, commanding exceptional rent levels. The post-bomb refurbishment of Tower 42 could not, however, overcome the inherent defects of the building - its huge central core and cramped floor areas. Communication between floors is minimal.
The tower can be compared to a series of headquarters buildings stacked one on top of the other. The form of the interior will be legible in the northern elevation, where the building opens up to the outside world, with office floors punctuated by sky gardens - social spaces breaking down the uniformity of the section.
To the south, a concentration of doubledeck lifts, stairs and services provides both a barrier against the sun and core-free, highly flexible office floors. East and west elevations are double-thickness ventilated facades, both transparent and energy efficient. KPF claims that tenants' energy bills could be reduced to virtually nil if they take advantage of the central cooled water circuit and install chilled beams rather than conventional air conditioning. The insulated container of the building effectively guarantees benign environmental conditions. The lower levels of the tower are to be public spaces, with retailing and restaurants - a further restaurant will occupy the top floor.
For a century, the office building has been at the forefront of architectural evolution and office development - the prime determinant of urban form in many of the world's leading cities. It is surprising, in the light of this, that office design is so widely seen as an unrewarding and even demeaning calling, inferior to work on, say, museums, housing or schools.
The image of the office building as an insensate monolith, unresponsive to the needs of society and the individual, largely accounts for this prejudice. Since the Second World War, the office building has been perceived as an instrument of globalisation and the imposition of a universal business culture - the reaction has been passionate and sometimes violent.
KPF's office projects need to be seen in that context. Though forged in the tradition of American workplace design, the practice has led the way in developing projects that respond to specific circumstances of geography, climate, history and social custom.
Energy issues are just one aspect of KPF's innovative approach, but, in more senses than one, it appears that the practice is letting fresh air into the world of office design.