The Dane is a hard act to follow

A brave Mancunian is taking over where Arne Jacobsen left off. Jonathan Glancey reports

Oxford colleges have been building on a large scale over the past few years, shoehorning extensive new student accommodation into old courtyards and car-parks. At the same time, dreamy old spires have been given the Baywatch babe treatment, looking far too groomed and out front for their 500 years. The high-street walls of Magdalen College, for example, 14th- century somewhere beneath their smooth ashlar skin, are now free from the mark of medieval masons, and looking no older than the brand new Gothic- meets-Greek-meets-Cotswolds-farmhouse quad the college is building to the kaleidoscopic designs of Demetri Porphyrios on Longwall Street.

Throughout the city, architects are struggling to speak a language of architecture at once contemporary and respectful of the past. Sometimes that language is as clear as a bell, at others as baffling as Beowulf.

The language Stephen Hodder has had to learn while extending St Catherine's College is Danish Modern. In fact his brief, to design an extension to Arne Jacobsen's early Sixties college, has been among the most difficult in the great rebuilding of Oxford. This is because the college the celebrated Danish architect built - chaste, rigorous and Platonic - was meant to be all of a piece. Jacobsen even designed the cutlery laid on the Jacobsen tables in the Jacobsen hall. In the stentorian words of the critic Reyner Banham, this Modern Movement college represented an "absolute architectural morality with no room for improvisation and no room for growth".

A wave of architectural immorality swept the senior common room at St Catherine's two years ago, when the dons decided to hold an architectural competition to extend the college along the banks of the river Cherwell. The winner was not a well-known London name, although several competed, but Stephen Hodder from Manchester, who made the brave and difficult decision to extend St Catherine's in a style that spoke the language of Jacobsen without copying its ever-so-precise phraseology.

The new buildings, comprising high-quality student accommodation (high- quality, lucky things, because student rooms are hired out during summer vacations for lucrative conferences), are more complex in form than Jacobsen's orthogonal originals, yet retain the chaste restraint that so characterises these memorable, if dispassionate, buildings.

Slightly to the north of Jacobsen, Hodder's extension is built of pretty much the same materials - concrete and fawn brick. But where Jacobsen's buildings are essentially symmetrical, Hodder's offer one face to the riverbank and another looking back to the heart of the college. The way the architect resolves these two fronts is masterly: there is no sudden jump, just a continuous transformation. The way the buildings are planned means students have a much greater degree of privacy than Jacobsen allowed them. In fact, the only way to have privacy in a Jacobsen room is to draw the wall-to-ceiling curtains, or to invest in a set of venetian blinds, which would be beyond the means of most undergraduates and would, in any case, upset the purity of the design.

These new buildings are attractive, unpretentious and show how an architect can add to the work of one of the 20th-century "greats" without toadying or trying too hard. Some might say that Hodder's design is too quiet, that, to create a true counterpoint to Jacobsen, the architect should have raised his voice a little louder. Yet the abiding quality of this new range of collegiate buildings is its rightness. Stephen Hodder and his colleagues have shaped buildings that belong in this odd location, a place of Sixties Scandinavia and absolutist architecture. They belong to both the severe, impeccable world of Arne Jacobsen and to the gentle riverbank that meanders past this place of ancient and modern learning.