Powerhouse In transforming Bankside power station into the Tate Modern, Herzog & de Meuron has created a flexible gallery which retains the monumentality of the original building . Photographs by Rich
Tate Gallery Director Sir Nicholas Serota has been at pains to point out that the Tate Modern project - completed next month, five years on from the appointment of Herzog & de Meuron as architect and Sheppard Robson as executive architect - is 'not about restoration'. Serota is adamant that 'this is not a heritage monument'. Yet, by selecting Herzog & de Meuron, then a relatively unproven practice, and rejecting more radically transformational proposals by, among others, David Chipperfield and Tadao Ando, the Tate deliberately ensured that the essential identity of Sir Giles Gilbert Scott's monumental temple of power would remain unchanged. As Harry Gugger of Herzog & de Meuron insists: 'It's not about restoration, but it is about working with Scott and not against him. In a sense, we had to battle with the building, but we never wanted to destroy it or spoil it.' Both Ando and Chipperfield, for example, would have felled Scott's 99m high chimney. Herzog & de Meuron settled for removing the 'shoulders' which flanked it, giving the building a distinctly Deco look (now largely lost).
It must be said immediately that Tate Modern (as we must call it) lives up to expectations. It will take its place immediately as one of the great art museums of the world, memorable as much for its locale, in a hitherto neglected quarter of London, and physical context as for the works of art it contains and a further affirmation of the fact that converted buildings are great places to show pictures and sculpture. Of the long run of conversions, indeed - which includes Gehry's LA Temporary Contemporary, Paris' Musee d'Orsay and the Hamburg Station in Berlin - this is the most ambitious and successful to date. Some feared that Herzog & de Meuron's aesthetic - 'tactile, sensuous, pure' as an admiring Serota describes it - might be at odds with the heavyweight interior of the power station. Yet the finished product reflects an admirably fine balance between respect for what existed and the need to innovate, transform and adapt it to new use. As Gugger (who has worked on the project with Herzog & de Meuron founding partner Jacques Herzog from the beginning) points out, Bankside Power Station was always something out of the ordinary. Scott (1880-1960), was brought in to provide an acceptable architectural cladding - the fragility of his brick veneer became apparent during the reconstruction - for a building which (though it replaced an existing coal-fired power station) many thought should never have been permitted on such a sensitive site. (Finally completed in 1963, Bankside was decommissioned by 1981, though a vast substation, one third of the entire building, was retained in use and provides space for future expansion.) Scott conceived the building as a symmetrical urban monument, with the single great chimney as its focal point - so vital was symmetry for Scott that the south and north facades of the building were given an extra bay to the east, concealing a void and purely for show.
Herzog & de Meuron's trademark, two-storey 'lightbeam' does not reiterate this symmetry. This is logical in practical terms and, in Harry Gugger's view, reflects the history and changed function of the building. It could also be seen as a symbol of the tension between industry and art implicit to the project. The raw material of the conversion, leaving aside the operational substation, consisted of two main elements - the great turbine hall, always a noble space, 155m long, with a clear internal height of 26m, and the former boiler house to the north, which was packed with machinery and had to be completely gutted. The turbine hall, with its intermediate floor removed (apart from one section, retained as a bridge link accessing the galleries) has become a 35m high 'street', an inside-outside space, potentially cold in winter and warm in summer, and open late into the night. The ramp which sweeps down from street level at the west end is made for crowds - though it is now estimated that up to 60 per cent of visitors (at least two million annually) will arrive via the river entrance, most having crossed Norman Foster's Millennium Bridge from the City. Despite new interventions (the 'lightboxes' along the north side which provide views from the gallery levels), the turbine hall is recognisably an industrial space - the huge gantry cranes have been retained for transporting heavy sculpture. The enormous bookstore is neatly tucked away and only really large and robust works of art will be allowed to intrude.
A regrettable note of banality is introduced by the new pitched skylight, which replaces an elegant lightweight concrete and glass brick structure found to be in poor condition. 'It could have been repaired,' says Gugger, hinting at some of the tensions underlying the project. 'In Switzerland, it would have been. We were told it was too costly, that the skills didn't exist here. Destroying it was criminal.'
In tune with Serota's vision of more formal, fully-serviced gallery space contrasting with the as-found grittiness of the turbine hall, the former boiler house has been filled with four new floors, three of which contain the core display space of the new Tate while level two (ground level) contains a large cafe, auditorium and offices. The galleries - 6000m2 in total - are, of course, the key to the success of the project and reflect a close collaboration between the client team (led by Tate buildings director Peter Wilson) and architect. Much is made of Herzog & de Meuron's artistic interests - 'I first went to Millbank just to see the Rothkos,' Jacques Herzog recalls. Now the Rothkos are hung at Bankside in a gallery of singular gravitas. Other galleries contain everything from Picasso and Matisse to Beuys, Hirst and Emin. A 12m double-height space at the west end of the building, lit by one of Scott's spectacular 'cathedral' windows, shows huge works by Beuys. Herzog was happy to provide galleries with a traditional sense of enclosure, sharing Serota's distaste for the 'cardboard walls' of the 1970s. 'We certainly didn't want the provisional look of the 1970s, of the Pompidou Centre say. But equally we didn't want permanence and immovability,' he explains. It is, in fact, possible to completely reconfigure all the gallery floors - only the four service cores are structural - by moving the walls to make new spaces. Yet the 5m high rooms look reassuringly solid, with doors on a human scale - the jambs can be easily dismantled if big works of art are to be moved in or out.
Harry Gugger believes that, as the power station was fired by oil, the Tate Modern is 'fuelled by light'. A deep, multistorey structure like this cannot rely entirely on natural light. The lighting strategy supplements controlled daylight with artificial light - so subtly that you move from one to the other without perceiving a change. Where galleries are lit by windows, these can be shaded or blacked out as necessary. Herzog & de Meuron do not see these spaces as simply neutral containers. Much thought was given to the floors, which are either of polished concrete or raw- sawn white oak boards, simply nailed down - the same material is used on the main staircase. 'It will get dirty and could look awful in five years. But in 30 years, it will look great,' says Gugger. If the boards are damaged, however, for example by heavy sculpture, they can be cheaply replaced.
Far from being precious, Herzog & de Meuron's fit-out has a robustness which should stand up to the crowds - the bold timber sections of the staircase handrail, for example, are a delight. This is a building you stomp, rather than tiptoe, through. It can accommodate the school parties and backpackers, yet has an inherent delicacy which will be apparent to anyone who stands in that room of Rothkos for a few minutes.
The two-storey 'lightbeam' has elegance to offset the industrial strength of the building on which it sits. It contains (at level six) mostly plant, with an agreeable clubroom (for Friends of the Tate - I foresee an expanding membership) which has splendid views of the river and City. On level seven, a 160-seat restaurant, with the same prospect, is soon likely to prove inadequate in size. If you walk along the 'lightbeam', passing the shaft of the chimney, you pass a fireplace, neatly set into chimney wall - who says that the Swiss lack a sense of humour?
Tate Modern confounds those who argued that converting an old building was a cop-out. For some, the transformation may be too radical - though it was Herzog & de Meuron who argued, successfully, for the brickwork to be left uncleaned, for the patina of history to remain. Far from being an easy option, conversion throws up all sorts of problems and dilemmas. It would have been difficult to make Tate Modern anything but impressive: clearly the turbine hall had to remain as a great public space. But the transformed building has become a remarkably flexible container for art, while retaining the illusion of permanence and monumentality. This, I believe, was what the Tate envisaged and what it has got. Above all, Tate Modern is a new slice of city in its own right. Serota is well known for his defence of the avant-garde in art. This project establishes him as a leader of urban regeneration. Southwark will never look back after this.