Demolition or restoration: What should happen to Glasgow School of Art?

Shock, heartbreak and devastation were the feelings expressed by most over the weekend as news spread of the second massive fire in four years at Glasgow School of Art.

But now thoughts turn to the future. Can the building, which has been reduced to "a shell", be saved and restored or will it have to be taken down and rebuilt from scratch?

It was undergoing a £35m reconstruction following the first fire in 2014 and experts have said a rebuild this time around could cost at least £100m. So what next for the Mack?

"There is hope," says a newly-hung sign on the firefighter statue outside Glasgow Central Station. It's a nod to the aftermath of the previous fire in 2014 when someone hung a "Thank You" sign in the same place.

However, that hope was dampened somewhat over the weekend by Prof Bill Hare who said there was a "growing consensus" the globally-significant building might have to be pulled down.

The deputy director of The Beam Research Centre at Glasgow Caledonian University, warned that the art school building could be structurally unsound.

He compared the intensity of the blaze with a fire which started in the roof of a building housing Victoria's nightclub in nearby Sauchiehall Street in March.

Within days of that fire, Glasgow City Council confirmed it would demolish the building.

Prof Hare told BBC Scotland: "At that stage the decision was taken fairly quickly to demolish that building.

"However, the Mack being such a globally-recognised building of significance, this would probably have a bit more deliberation before they come to that decision.

"But the consensus is beginning to grow over the last 24 hours that that might very well be the case."

However, all hope is not lost, according to Prof Hare. He said if it was not possible to retain the facade of the building, it may be possible to take down the building brick-by-brick and rebuild with a new internal frame.

Other experts have been more upbeat in their early assessments.

Miles Glendinning, a professor of architectural conservation, told BBC Radio Scotland he would be "very surprised" if the building had to be knocked down and rebuilt, saying the walls could instead be reinforced.

He believes the building "should be restored and will be restored".

And that's an view echoed by Labour MP Paul Sweeney.

"The Mack will endure" was how he ended a series of tweets he posted on Sunday which included several videos showing the damaged building from different angles.

The Glasgow North East MP, who is also director of the Glasgow Building Preservation Trust, was escorted around the exterior of building by the fire service on Saturday night.

He described part of the 1909 library extension as a "tangled mess of charred timber and distorted steel joists" - but added that some structural joists and outer walls appear to be solid and stable.

He said the eastern wing, which dates from 1899, appears to have been hit worse - with some of the stone "baked", fractured or "visibly moved" by the heat.

Speaking on the BBC's Good Morning Scotland radio programme, he said he believed the "building ought to be saved for the nation".

He said: "It was clear that the interior is almost entirely lost.

"The one thing that did strike me was that the main structural beams appear to remain largely intact and are tying the wall-heads back into the building.

"That was a reassuring sign that there hadn't been any obvious movement in the main facades of the building."

He added: "Whatever needs to happen to make this building realised again as Mackintosh's vision has to happen.

"This is building is the pinnacle of achievement of British art nouveau architecture and it's my job as a member of Parliament to go down and say this building ought to be saved for the nation."

Speaking at the scene of the fire on Saturday, renowned architect Prof Alan Dunlop, who was trained at Glasgow School of Art, said some of the aerial and drone footage looked like something from World War Two.

He has questioned whether a reconstruction, done brick-by-brick, would be truly authentic.

And he has said he believes Charles Rennie Mackintosh himself would favour a modern building on the site.

For John Glenday, editor of architecture and design magazine Urban Realm, the discussions over what to do now are not new.

"We've had these arguments before, after the last fire in 2014," he told the BBC's Kaye Adams radio programme.

"Do we rebuild? Do we build something new?

"This time around, however, the equation has changed," he said.

"The fire last time was much less severe. A great deal of the historic interiors actually survived thanks to the heroic efforts of the firemen. This time it's different."

For him the idea of facadism is looking like "the number one possibility at the moment".

This would see the stone walls and exterior appearance of the school retained and then "something new created within".

Mr Glenday also raised the possibility of using this as an opportunity to let a new up and coming young architect "prove their mettle and build something of equal significance".

The Mackintosh library is said to be one of the most documented rooms in the world.

Writing in Urban Realm, Robin Ward, author of Exploring Glasgow, The Architectural Guide, said a complete copy of the building would be doable - as the Mack is comprehensively documented, with a detailed digital modelling of the building done after the first fire.

A full-size prototype of a library bay was also built as part of restoration work.

Prof Miles Glendinning, who is director of the Scottish Centre for Conservation Studies, told BBC Scotland: "A Glasgow School of Art project team (made) a digital recording reconstruction of the whole building, not just the bit that was affected before, down to the nearest millimetre, outside and in, using photos and measured drawings.

"So the building still exists digitally even if the inside is for the moment physically absent."

But, following the latest fire should it be rebuilt as it was, where it was? Robin Ward also pondered what Mackintosh would do, were he around today?

He concluded: "Perhaps the school's architectural students should be given a chance to reinvent the place. Charles Rennie Mackintosh was young when he designed the Mac, and created a masterpiece."

BBC Scotland News asked people on social media if the art school should be rebuilt.

Responding on Facebook, Moira MacGregor said: "Yes! This was something exceptional. Even if rebuild is not original, it's still Mackintosh's work. His vision...Please, please rebuild."

On Twitter the responses were mixed but Hazel McNeil was firmly of the view that something fresh was required. "It's gone. GSoA should commission a new talent," she said.

But John Hutcheson felt it was definitely worth saving. He said it was "an iconic building" and added: "We would not be asking this question if it was St Paul's, a royal place or similar."

And Joe from East Kilbride, who is in his 80s, called in to the Kaye Adams programme on Monday morning, to say he believed the building "could and should be restored". He contributed to the fundraising efforts following the fire in 2014 and said his cheque this time around was "already written and in the post".