THE architects who played a key role in the restoration of the Mackintosh Building have told MSPs of their devastation at its second ruinous fire.

Page\Park Architects, in their written submission to the culture committee of the Scottish Parliament, said they feel a "deep and enduring regret" that fire protection measures had failed at the Glasgow School of Art building.

David Page, the director of the architects, as well as the managing director of the building contractors, Keir Scotland, Brian McQuade, are due to appear before the Culture Committee tomorrow.

The architects, retained by the Glasgow School of Art (GSA) as conservation experts for 'the Mack' since the early 1990s, said the second fire at the world-famous building was an "an appalling event which has left our dedicated team of conservation architects completely shattered."

The companies submission also adds more insight into which fire-prevention and detection systems had been chosen to protect the building.

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The firm insists that it had learned lessons from the first fire, which consumed much of the building's west end in 2014, after a hot projector ignited foam in a student's artwork.

It notes: "We had carried forward lessons from the fire of 2014 to ensure that the restored building would be properly fire protected and we required the contractor to put in place appropriate fire protection measures during the construction process.

"It is a matter of deep and enduring regret that these measures were unsuccessful and, like the members of this committee and all others in Glasgow, Scotland and beyond who have an interest in this appalling event, we also need to understand precisely what happened and we await the outcome of the investigation by the Scottish Fire and Rescue Service."

The architects say that at the time of the June fire, the reconstruction and conservation works in the building were well advanced, and were due to be completed early next year.

Glasgow City Council Building Control had visited the site on a number of occasions, they say.

It adds: "The installation of the fire mist suppression system and air aspirating smoke detection system, as well as mechanical and electrical installation, were proceeding in accordance with the agreed plans and programme, under the management of the contractor."

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The architects submission, for the Committee's second hearing on the fire, said that before the first, 2014 fire, a water mist fire suppression system had been "very close to being completed."

After that blaze, fire safety upgrades for the building were agreed upon in 2015/16, including "comprehensive provision for fire stopping and cavity barriers in the building" as well as L1 (or earliest possible detection) fire alarms throughout the building, and " automatic smoke and heat exhaust ventilation systems to provide a path for the smoke to be exhausted out of the building" as well as a low pressure mist fire suppression system.

It was also agreed to "bring those areas of the building not directly damaged by the fire up to a standard which would be consistent across the whole building."

This work included "enhancing doors and glazed screens in corridor areas which contributed to the compartmentation of the building."

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Kier Construction, which was working on the building when the second fire took hold, issued monthly reports "confirming that fire measures were being tested and monitored regularly."

In its own submission, Kier said it is "extremely saddened" by the second fire.

The company says it was "almost ready to hand over a restoration of the very highest quality" to the GSA.

At the time of the June fire, it says, "the building was largely wind and watertight and the internal works were well underway.

"Work was ongoing to restore the floors, plastering and painting of ceilings and walls."

Since the fire, the GSA has ended its contract with Kier and, it says, it has "been unable to access the site."

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A document for the MSPs says that insurance for the building was held in the name of the GSA and Kier.

This was an Owner Controlled Insurance Programme (OCIP) and covered damage to the Mackintosh Building including fire.

It also re-iterates the point often made by the GSA that at the time of the June fire, it was "not part of the GSA’s operational estate and was in the management and control of Kier Construction Scotland Limited."

It adds: "We are working to assist the Scottish Fire and Rescue Service, Glasgow School of Art and other relevant parties to help determine the cause of the fire."