Meanwhile, 14 architects are in running for the reconstruction
The fire that destroyed the Mac library in Glasgow was caused when expanding foam was sprayed too close to a projector, official investigators have found.
Final-year students were setting up their degree show projects in the basement and holes in some pre-built foam panels were being filled with the spray foam.
Flammable gas used as a propellant in the canister was sucked into the projector’s cooling fan, setting it alight. A foam panel right behind the projector then caught light.
The flames quickly spread to timber panelling and through voids around the basement studio and then into the library two floors above and up through the rest of Mackintosh’s 1909 masterpiece.
Tom Inns, director of The Glasgow School of Art, ruled out any legal action over the tragedy.
“It was an unfortunate accident and like any accident a whole series of events conspired against us to create the incident,” he told BD.
“It was associated with a particular piece of work and circumstances but no finger-pointing is going on.”
The Scottish Fire and Rescue Service (SFRS) report also confirmed that a fire suppression system was in the latter stages of installation at the time of the fire but was not operational.
Inns revealed that the final commissioning of this system had been delayed by the discovery of a small area of asbestos in the building’s foyer which required specialist removal.
This had to be delayed until after the busy degree show period, he said.
“It’s one of the great tragedies that we were so close to having it in place,” he said.
Lessons learnt from this and the detailed investigation by the fire service would inform the reconstruction of the Mac, he said.
He announced that 14 expressions of interest had been received for the contest to rebuild the Mac by the deadline this month. A shortlist of about half a dozen should be announced before Christmas.
“People have asked if 14 is fewer than we expected but it’s about right if you think about how specialist this work is,” he said.
“They are UK and also international architects and all 14 are completely credible.”
The full report
The fire started in Studio 19 located in the north basement, west wing of the Mackintosh Building within a student exhibition space (approximately 6m X 2.5m, constructed of chipboard and wooden studs).
The student work comprised high expansion foam panels (these were fabricated outwith the exhibition space), and were approximately 50-75mm in depth, fastened to three of the walls, with one wall left blank to receive projected images from a projector mounted on the opposite wall.
At the time of the incident visible gaps between the foam panels were being filled-in by applying foam directly from a canister of expanding foam.
The fire originated within a projector mounted on a shelf approximately 1.7m from the ground and located on the south wall of the studio. (Projector details - Epson EMP-TW680; this was the property of GSA and had been purchased in 2008; it was maintained by GSA Technical Services Department; it had been subject to inspection, cleaned and tested prior to being loaned, with guidance, to the student; annual portable appliance testing (PAT) had last been carried out in December 2013).
Fire was caused when flammable gases (Isobutane, propane and dimethyl ether) used as a propellant within a canister of expanding foam was discharged in close proximity to the projector. These flammable gases were drawn into the projector cooling fan. The SFRS report has ruled out ignition being caused by this equipment being defective, and SFRS could find no evidence to suggest it did not operate as the manufacturers intended. It is likely that indirect ignition of the flammable gases occurred as it passed in and around energised electrical components of the projector.
Once ignited the flame front would have grown in size consuming plastic components and the plastic casing of the projector, flames then impinged onto the foam which was placed on the wall directly behind it.
As flames and hot gases reached ceiling level of Studio 19 they spread horizontally, igniting further timber panelling and entered voids in the walls on both sides of the doorway of Studio 19.
Flames then travelled through the voids in the walls into Studio 31 on the ground floor, directly above Studio 19. Fire spread vertically either side of the doorway and also horizontally behind the timber panelling, in a westerly direction, in Studio 31. At least four voids run vertically in the walls of Studio 31 and these allowed unchecked fire spread to areas above, as well as on the same level.
One of these voids allowed lateral access to Studio 32 at ceiling level. From Studio 32 the fire spread through voids to the Mackintosh Library above. The construction, layout, and high fire loading (timber furniture, panelling and books) meant that the room and its contents became totally involved in the fire. From the Library the fire spread vertically via voids to the Library Storage Space above and then into Studio 58 via these same voids.
Returning to the ground floor within Studio 31, fire spread via all four vertical voids to the first floor Studios above 43, 44 and 45. The fire achieved this by breaking through timber panelling which cover the voids, allowing access into the corridor outside the studios.
Fire then spread laterally from the Professors’ Studios to Studio 57. From here, the fire also spread into Studio 58.
A major contributory factor for the fire spreading throughout the building was the number of timber lined walls and voids, and original ventilation ducts running both vertically and horizontally throughout the building. The vertical ventilation ducts consisted of both brick-lined, (located within the walls), and timber ducts (mounted on the wall surface). The brick-lined ducts were formed within the structure of the walls. Horizontal ducts were constructed of timber and, in some instances, sheet metal. A vertical service void ran the entire height of the building to roof level and acted like a chimney. It allowed flames, hot gases and smoke to travel vertically.
A fire suppression system, designed to enhance existing fire protection measures, was being installed and was in the latter stages of completion; at the time of the fire the system it was not fully commissioned and was not operational.
In the immediate aftermath of the fire the GSA implemented its business recovery plan. This has ensured the School was able to maintain effective operations, including the annual Degree Show and graduation, and maintaining postgraduate taught programmes over the summer concluding with the Graduate Degree Show in September 2014.
Since September 2014 and the start of academic year 2014/15, the School has been operating business as usual, with staff and students decanted from the Mackintosh Building relocated to other GSA buildings and the Tontine Building in the Merchant City through a lease with Glasgow City Council.
The Glasgow School of Art has commissioned an external review of its management of the critical incident.
Now that the SFRS has concluded its investigation into the cause of the fire, The Glasgow School of Art will be reviewing the specific lessons to be learnt from the incident. Information from the SFRS Fire Report will also be used to inform the Mackintosh Building restoration and GSA’s broader approach to health and safety management going forward.
Progress is being made on plans for the restoration of the Mackintosh Building. The Building is now wind and water tight, is being cleared with services being reinstated to allow works to commence, and specialists from Kirkdale Archaeology are forensically excavating the remains of the Mackintosh Library, the outcomes of which will inform the restoration.
The recruitment of the internal project team is progressing and the appointment (in line with EU procurement requirements) of the design team and the external project management team to undertake the restoration has commenced.
A special Board Committee has been established under the leadership of Eleanor McAllister OBE to oversee the restoration project. We aim that the building will be fully restored and operational as a working art school, exhibition space and visitor attraction between 2018 and 2019.
This story first appeared on Building Design here.