The historic O2 ABC has been deemed ‘economically unsalvageable and unrepairable’ by construction experts.

Assessments of the Sauchiehall Street building have revealed the extent of the damage caused by the Glasgow School of Art fire in June, last year.

The damning report, submitted with plans to demolish the building, states that the ABC1 and ABC2 suffered ‘catastrophic fire, smoke and water damage’.

According to a report filed with the application by Prime Structural Solutions to Glasgow City Council, the main issues stem from the complete collapse of the roof, threat of asbestos, water damage and destruction of all services inside the building.

Read more: In pictures: Looking back on the history of Glasgow's O2 ABC

As well as being doused with thousands of gallons of water on its own, the elevated location of the Glasgow School of Art has resulted in the ABC site being subjected to the runoff of all extinguishment water.

There is still a ‘large volume’ of water present in the C-listed building, which has destroyed all fixtures and fittings and seeped deep into its structure and fabric.

Experts say the impact of the water will have a ‘major bearing’ on any future proposals for the building or site.

The wall separating the ABC2 and the Mackintosh building is described as acting ‘like a retaining dam’ for much of the water that was pumped into the GSoA building.

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Prime Structural Solutions state that the major steelwork elements of the building have collapsed and are placing a ‘significant’ weight onto the general structure, that it was never designed to cope with.

Steel on the upper floors has also completely collapsed, and have fallen through the floor.

The building is primarily relying on its ‘steel framed structure’ to stop the floors from completely collapsing.

Read more: Plans to demolish O2 ABC after Glasgow School of Art fire

The roof of the ABC2 is significantly damaged after being “hacked” into by the fire service to allow water to be hosed into the floor.

Part of the roof is also being used to support scaffolding to the rear facade of the Glasgow School of Art.

Surveyors have been unable to fully examine the extent of the damage to the floors due to the amount of debris and materials created by the inward collapse of the roof.

All of the services inside the building have been destroyed or damaged.

The drainage, heating, cooling, ventilation, electrical and alarms systems are all now useless.

Concerns have been raised about possible toxins in the building caused by plastics, polymers and water from the River Clyde used to extinguish the blaze.

The report also states that original drawings for the both the buildings revealed that ‘asbestos materials’ were specified to be used within the construction.

It adds: “The process of accessing, supporting, clearing, remediating, salvaging, preparing, dewatering, drying, decontaminating the entire building and stripping out what, is an already now suspect building with regard to loss of structural integrity and the process of effectively taking this back to the skeletal frame and bare structure and dealing with the extent of trapped fire debris, trapped water in and under the building would be a very technical, protracted and a high risk process.

Read more: Glasgow School of Art Fire: Fire-ravaged O2 ABC boarded up as future remains uncertain

“The potential for latent problems to emerge would be enormous.”

As previously reported by the Evening Times, Glasgow City Council have boarded up the building to allow them to relax the cordon that has been in place since the fire.

The plans to demolish the building are due to go before Glasgow City Council.