“WHY we sometimes have to admit defeat” is the surprise headline of an article in the latest newsletter of the 20th-Century Society. At stake is a landmark building of the 1960s, the Southside Halls of Residence at Imperial College in London, listed Grade II and designed by Sheppard Robson, architects of Churchill College in Cambridge and one of the leading practices of the period. The building has a regular place in books on modern architecture. It is illustrated in Pevsner and English Heritage’s Guide to Postwar Buildings.

Designed in 1960 and completed three years later, it fronts on to leafy Prince’s Gardens, a square just across Exhibition Road from Imperial College. It has a powerful presence inspired by Corbusier’s famous Unité d’Habitation in Marseilles, soaring ten storeys high but with strongly horizontal lines. Bands of panoramic windows proclaim the students’ rooms, accessed by deck terraces between each trio of floors.

As at the Unité, these are streets in the sky with common rooms, kitchens and laundries. The student rooms are grouped in four vertical halls of residence with elegant spiral stairs; at the top of each is a penthouse for the warden. The ground and first floors contain refectories and public spaces.

This was built in the heroic age of Modernism. Today Southside is forlorn, its shabby concrete witness to years of poor maintenance while the bold outdoor steps to the first deck are locked off and accumulating litter.

Andrew Rabeneck, of Imperial College, says: “These buildings were erected under very stingy cost limits and provide poor quality in thermal terms. We were faced with spending £38 million on refurbishment and ending up with fewer student beds than we started with.”

The college has therefore decided to sweep the Sixties block away and replace it with new student accommodation continuing up the east side of the square. This is designed by Kohn Pedersen Fox and is lower and more in keeping with the scale of the Victorian houses on the west of the square.

Attending a presentation, the 20th-Century Society casework committee expected to discuss aesthetics and finance but were left speechless by an engineers’ report which stated that 70 per cent of the structure was defective. “We were confronted by the serious reality of a failing structure,” says the society.

English Heritage is not objecting either, so the battle has been left in the hands of a few determined residents. The architect Daniel Serafimovski has drawn up a dossier citing an earlier scheme to modernise and adapt Southside by Rick Mather, with suggestions of his own for improving access and providing the ensuite bathrooms Imperial seeks — a great help for conference lets.

Enter the engineer Alan Conisbee, fresh from helping to complete immaculate restorations of Wells Coates’s Isokon flats, Lubetkin’s Highpoint I and II and his Wynford House in Islington – this last condemned by the council. He explains: “Southside is constructed of floors and internal walls of in-situ cast concrete, with precast cladding panels. The in-situ concrete is spawling at the exposed outside edges, but this is a minor part of the structure and can be treated by drilling holes and inserting capsules. Cracks around the cladding panels can be sealed by injecting resin.”

As for 70 per cent of the cladding panels being defective, he says “some of the deformations are so slight, of the order of a millimetre, as to be insignificant. Yet the 70 per cent figure has been repeated over and over again and a horror story set up. It is misleading.”

He also strongly questions the sustainability of rebuilding proposals. “Hundreds of thousands of tons of concrete will have to be broken down into hardcore or used for landfill, while huge quantities of sand and gravel will be required to construct new buildings of similar volume to meet similar needs.” It’s a good point: can an environmentally responsible organisation, especially an academic one such as Imperial College, play so fast and loose with resources?

Conisbee makes another point. As circulation within the building is organised vertically, it would be practical to refurbish the building a section at a time, avoiding the wholesale decanting of students from the site.

Mark Whitby, the engineer who worked with Rick Mather, concurs. “These are very solid buildings. They are suffering and need a lot of attention but they are not derelict. Recently there was even a report saying the Hayward Gallery was suffering from concrete cancer and had to be demolished.”

Math himself says: “I feel there is no need to pull the building down. Our plans improved circulation and provided disabled access to every student maisonette by means of new lifts.”

Time is short. Westminster council is minded to grant planning permission, but the 20th- Century Society, fired by the latest evidence, is calling for a full reassessment.

Marcus Binney is president of SAVE Britain’s Heritage

Explore Property

• Buying & Selling

• New Homes

• Overseas

• Interiors

• Investment

• Gardens

• Cool In Your Code

• Specials

• First-time buyer

Times recommends

• Second homes: credit crunch casualty or money-spinner?
• How I built my own sliding house
• Top 10 incentives for house buyers