Glasgow School of Art is gone, says Alan Dunlop, and to honour Charles Rennie Mackintosh's legacy, we need to come up with new ideas for its replacement.

In 2014, Charles Rennie Mackintosh's Glasgow School of Art was assaulted by fire. The neighbourhood was evacuated, people watched in horror as flames engulfed the building.

The damage was devastating but was contained by extraordinary feats of firefighting to the west wing of the building. And although the exquisite library was lost, no-one was killed or injured. The Mack has been dark since, while extensive restoration has gone on at an estimated cost of £35 million.

Fast forward four years and, on Friday last, a new conflagration consumed the building. This time, the flames were hungrier; they lit up the night sky and the neighbourhood again cleared of its residents.

The damage is brutal: the entire interior, east and west is gutted, and the roof is gone. The renovated library, which was apparently almost complete, is lost, and what is left of the building is a distressed shell. The steel lintels above the windows that flooded the studios with light are twisted and buckled, and the exterior stone walls have been battered by millions of gallons of water pumped up Glasgow hills direct from the River Clyde, in another gallant effort from the fire service to try to save it. Again thankfully, there has been no loss of human life.

There is disbelief, and a simmering, almost palpable anger at this latest catastrophe. Shock that this world-renowned architectural jewel, entirely designed by Scotland's greatest architect, could have caught fire again.

There is disbelief, and a simmering, almost palpable anger at this latest catastrophe

Again too, are the urgent calls to rebuild "as before, stone by stone". Serried ranks of politicians, both local and national, and conservationists have lined up to say just how shocked they are, and to demonstrate the extent of their personal loss and grief that will only be assuaged by reconstruction. Moreover, Glasgow Council has stated: "There is a consensus emerging that the intention of the building control people, Historic Environment Scotland, and the Art School is to save the building". All this, while the building smoulders.

The sad truth is that there is very little left to restore. I have been asked repeatedly how the building might be restored, and at what cost. My view is that this question is pre-mature, and yet an entirely understandable reaction to chaos and unforeseen loss. Certainly, any building can be replicated. And after the first fire, the building was extensively digitally archived. But surely the question is, ought it to be replicated?

Charles Rennie Mackintosh was a superb architect, a gifted artist, and above all, a dynamic innovator. He believed that the artist "cannot attain to mastery in his art unless he is endowed in the highest degree with the faculty of invention".

It is my contention that he would not approve of pastiche or replication. Moreover, what has not been lost in the fire is the 110 years of history, the spirit and good will of the thousands of students, artists, and architects who have worked there, and who, consciously or subconsciously, will have been affected by Mackintosh's essence.

The sad truth is that there is very little left to restore

Mackintosh won the competition for a new art school in 1897, while working as a draughtsman for Honeyman and Keppie, and attending the old art school part-time.

The building was completed in two phases. The first phase, completed in 1899, was the art school studios. Designed for drawing and painting, these spaces featured large north-facing windows that allowed natural light to flood in – nothing in the city was like it.

Mackintosh was not even invited to the opening – the partners took credit for the design and the building. But over the following years he matured as an architect, honed his pared but organic design skills, and completed the second phase, the west wing.

The entire building was testimony to his creative genius and artistry, and continued as a functional and inspirational art school until the first fire in 2014. It was a work of extraordinary skill, combining Scottish baronial architecture, innovative construction and discernible built tradition, with elegant influences from Japan.

Everyone loves Mackintosh now, but he was not always so well regarded in his home city. It was 15 years before Honeyman and Keppie deigned to make him a partner, and he did not thrive. He left Glasgow with his wife and fellow artist Margaret Macdonald when architectural work dried up, and after an unsuccessful attempt to start on his own. Then as now, Glasgow had a small clique of those in favour and Mackintosh was never one of them. He was an outsider.

Mackintosh's built heritage was not well well protected by the city fathers either. In 1945, the Bruce Plan proposed demolishing all of Glasgow's Victorian and Georgian city centre, including the Glasgow School of Art. Glasgow's notorious 1965 road developments obliterated Martyrs School in favour of a ring road and a football field.

It was not until the mid-1960s that Mackintosh's legacy was reappraised, and his reputation revived, largely due to the efforts of art collector and gallerist Roger Billcliffe.

As a designer, comparisons have been made with Frank Lloyd Wright, the great American architect. Now sadly, Mackintosh is best known as a marketing opportunity, with images of his buildings, art and distinctive text on tea towels and mugs.

Mackintosh would not approve of pastiche or replication

So, what will happen now? There will be an investigation into the cause of the fire, and a search for fault. There are questions to be answered about fire protection measures. For instance, if sprinklers were installed, why they were not operational?

There are matters of estate security and insurance to be cleared up. There are questions too for the school's board of governors and trustees, who issued a press release late on Sunday. It stated their intention to support existing students and plan for the coming academic year. This is laudable, but a note to editors also advised that: "The Mackintosh Building was undergoing a period of restoration following the fire in 2014, with day-to-day management of the site under the control of main contractor Kier Construction Scotland and was not part of our operational estate".

Some have interpreted the statement as an attempt to avoid responsibility for the building and the fire. Particularly after 2014, this is an unlikely defence. The school board are custodians of one of the most important buildings in Scotland.

At the moment, the future of Mackintosh's School of Art is uncertain, while the structural integrity of what remains is confirmed. Instead of attempting to turn back time and rushing to create a sad replica, however well-crafted, I hope that people will honour Mackintosh by considering alternatives that reflect his extraordinary legacy. I suggest that a full public debate is warranted, that includes the option of an international competition to design a new art school.

Photo by Jeff J Mitchell.