George Cairns created the extensive set of drawings, based on Mackintosh’s original 1909 building, when he was a PHD student there in the early 1990s.
Art school chiefs say the drawings, which are to be kept permanently in the official GSA archives, are the most comprehensive record of the building of their type in existence.
They will be used by the team restoring the Mackintosh Building in the wake of the devastating fire last May, which destroyed its iconic library.
Glasgow-based architects Page/Park have been tasked with restoring the building, including reconstructing its library, after being selected from a five-strong shortlist for the project, which is expected to cost up to £35 million.
Professor Cairns, who now works for the business school at Queensland University of Technology, in Brisbane, presented the plans to GSA director Tom Inns during a visit to the art school today.
The former student wrote in the wake of the fire of the “enormous pain and loss” he felt after reading about the blaze and its devastating impact.
At the time he wrote that what remained of the building should be “carefully stabilised and preserved, then for great architects to be invited to design a worthy intervention that will breathe new life into the school.”
Processor Cairns said: “I’m delighted to be able to return to Glasgow today after so many years and to be able to donate this set of drawings which I made as part of my doctoral thesis to the GSA.
“I hope very much that they will prove of interest and use to the teams working on the restoration of the Mack and to generations of students who have the privilege to study Mackintosh’s masterpiece.”
Liz Davidson, senior project manager for the Mackintosh Building restoration project, said: “We are keen to continue to access as much information as possible about the building in planning our approach to the restoration.
“Professor Cairns’ has already been generous in his time in liaising with the design team and these particularly detailed drawings are going to be an invaluable source of information.”
Firefighters received huge praise after managing to salvage 90 per cent of the Mackintosh Building and rescuing around 70 per cent of its contents, including the “vast majority” of the art school’s archives. However 90 oil paintings, including two by Mackintosh, and around 8,000 books and journals were lost.
A reopening of the building is not expected until the 2017-18 academic year at the earliest.
Students were putting the finishing touches to end-of-year projects in the Mackintosh Building when the fire caught hold at lunchtime on 23 May last year.
The blaze started in a basement area and spread swiftly through its west wing.
The official investigation found that the blaze was triggered by flammable gases from a canister of expanding foam. They were set alight when they came into contact with the hot surface of a film projector in a studio being used by a student, who has not been identified.