Architecture: Arrivederci to Brum's bit of Italy: Chris Arnot remains unconvinced that plans to glass over the arcade of Corinthian columns outside Birmingham's Town Hall will not lessen the building's grandeur

Unlike Rome, Birmingham was not built on seven hills. But as befits a building modelled on the Roman temple of Castor and Pollux, its Neo-Classical town hall has a suitably elevated position at the top of Hill Street and New Street.

It was designed 160 years ago by Joseph Hansom, better known, perhaps, for inventing the cab that bears his name. For more than a century the town hall held its own against many of Europe's top musical venues, and its architecture rarely failed to impress. As one 19th-century actor proclaimed: 'I believe there is not any building in England that can exhibit such a glorious range of columns.'

Those fluted Corinthian columns have stood with lofty dignity while the architectural turmoil of the Fifties, Sixties and Seventies raged around them. Unlike the beautiful adjoining central library, they survived the great destruction of Birmingham that occurred after the Second World War. Ironically, it is only now - after Brum has embraced Culture with a big C - that plans have emerged to alter the building's frontage.

The Town Hall is at the centre of a conflict between architectural purity and commercial flexibility. John Gummer, Secretary of State for the Environment, has approved a plan by the City Council to cover with glass an arcade of Roman-

style arches outside the front doors of the town hall to create extra foyer space and a new ticket office.

Work is due to start in the spring - much too soon for some members of the Conservation Advisory Committee, such as the local architect and lecturer Joe Holyoak. 'The city has enjoyed a huge dollop of Euro-money, about pounds 2m, which had to be committed by the end of 1993,' he says.

'The project has been pushed through faster than a scheme of this importance ought to have been. We're talking about a Grade 1 listed building, one of only a dozen in the city. It may be plain glass with no frames, but it will be a major change to a pure building.'

Mr Holyoak has no complaints about the quality of the proposed work by the City architects' Department. 'It is being done as well as it could be. The question is: should they be doing it at all?'

Certainly not, says Barbara Shackley of the Birmingham Victorian Society. 'I think it will spoil the frontage and take away its Victorian character. They should leave it alone.' She is also concerned at the incorporation into the Town Hall of what has been, until now, a public thoroughfare. Once the arcade of vaulted arches becomes a carpeted foyer, only a narrow strip of pavement will remain between the frontage and four lanes of traffic on Paradise Street.

William Howland, design manager for the city's Department of Planning and Architecture, points out that Paradise Street will be for pedestrians only by the end of the year. All the more reason, says Joe Holyoak, for leaving well alone. 'A more generous pedestrian space will make this arcade seem more pleasant. The town hall was designed in such a way that it connected with the street through this arched space. It's very Italian.'

Anthony Sargent, Birmingham Council's head of arts and entertainments, says Italians would have no qualms about blending stone and glass on such a building. He is committed to the scheme as a way of halting the Town Hall's decline since the new Symphony Hall lured away Simon Rattle's CBSO and many visiting top-line performers.

'Audiences,' he says, 'expect better refreshment facilities and pleasanter circulation spaces than the Town Hall now provides. Even the matter of entering the building needs attention. Newcomers have been known to circulate it completely before finding their door.

'Modern expectations are that a box office will be readily visible and accessible, and enticingly designed, and that a venue will have a reception/foyer space. What we are proposing will make some adjustments to the internal spaces without compromising the grandeur of the building one iota.' They've heard that in Birmingham before.

(Photograph omitted)