5.8.1 In the same week as the above letter of 5th April 2016 was written by ESP, the supervising structural engineering consultants Goodson Associates were advised by the contractor on the Phase 2 Schools, Galliford Try, that during the reconstruction of the collapsed gable wall at Oxgangs Primary School, members of staff of the contractor had reported to Galliford Try the discovery of an apparent lack of expected head restraints at the top of the walls.
5.8.2 At this stage, in early April, the Inquiry have been advised that Galliford Try had succeeded in acquiring a number of construction drawings for the four Phase 2 schools from WSP, the original design team structural engineers for the PPP1 schools.
5.8.3 Further investigations were undertaken by Galliford Try to establish the presence and form of any head restraints. The investigations undertaken established that in several situations head restraints had either not been installed or were inadequately spaced.
5.8.4 In response to this situation, a structural review to establish the capacity of a range of the masonry panels at Oxgangs School was undertaken by Goodson Associates, involving calculating the strengths of the panels on the assumption that head restraints had not been fitted. This review concluded that in the case of the majority of the external masonry panels assessed, it would be necessary to retrofit head restraints to achieve the necessary resistance to wind loading.
5.8.5 From the information provided to the Inquiry, it would appear that as early as 23rd March, the day after Galliford Try commenced their remedial work at Oxgangs School, Goodson Associates had already on behalf of Galliford Try carried out calculations on the brickwork panels in the Oxgangs School gable wall that had collapsed. These calculations, which predated the discovery of the missing head restraints, had assumed that the panels in question were restrained on all four sides i.e. that head restraints had been fitted.
5.8.6 The calculations completed by Goodson Associates on 23rd March 2016 showed that given the size, location and orientation of the largest panel, and assuming that head restraints were present in accordance with the original specification, which was subsequently found not to be the case, additional bed joint reinforcement or secondary steelwork in the form of windposts would still have been necessary to satisfy the required wind-loadings.
5.8.7 The Inquiry has been advised that this information, which demonstrated a requirement for not only head restraints but windposts to be installed, was not conveyed by Galliford Try to ESP or to the City of Edinburgh Council.
5.8.8 From an examination of photographs taken after the collapse of the wall, it is clear that neither windposts nor bed joint reinforcement had been installed in the wall.
5.8.9 An emergency meeting of the Council's Corporate Incident Management Team was convened at 12.30 pm on Friday 8th April 2016 following a request from ESP for a meeting. The information on this newly emerging issue was shared with the Council officers present. In addition to the Council officers this meeting was attended by a representative of ESP from the Edinburgh-based consultancy Infrastructure Management Limited ("IML") which oversees the implementation of the contract on behalf of ESP, and representatives of WRD, Goodson Associates, Amey and Galliford Try.
5.8.10 The record of the meeting states:
"...a further serious issue had been identified with regard to Oxgangs Primary School. Support at the head restraints was missing in some places and sparse in others offering insufficient support at wall heads which now posed an unacceptable risk and could cause internal walls to collapse. 21 panels had been checked at Oxgangs Primary School which had failed the accepted standard - equates to 20%. As a result of these findings it was deemed necessary that the school be closed until further investigation and remedial works had been undertaken."
5.8.11 The Inquiry was advised by Council officers as part of their evidence that the nature of the defective construction newly reported at this meeting was considered to be of major significance and the cause of great concern on the party of the Council officers present.
5.8.12 Under the proposed strategy for reopening the schools on 11th April 2016, it had been assumed that any further failure of the outside leaf due to poor embedment of wall ties would result in a collapse of masonry into an unoccupied exterior exclusion zone in the school grounds, an area inaccessible to schoolchildren and others.
5.8.13 However, the Council officers were now advised that a failure of the inner leaf of the cavity wall to resist wind-loading, as a result of the reported absence of or inadequacy of head restraints, could result in an inward collapse of masonry into a classroom or other area occupied by children, teachers or staff. The Council officers considered this to be an unacceptable risk.
5.8.14 The Inquiry was informed by officers of the Council who had attended this meeting that, whilst they understood the technical and causal issues were somewhat different, they were all inevitably aware of the recent fatal injuries caused to a pupil at Liberton School in Edinburgh through the collapse of an internal free-standing masonry partition wall on 1st April 2014. Although the cause of the collapse of the internal free-standing wall at Liberton School was quite different and in no way linked to the Oxgangs failure, the memory of it reinforced the determination on the part of Council officers that they were not prepared to take any risks which might have compromised the safety of the school population.
5.8.15 It was agreed by the Council officers present at the meeting that the Leadership of the Council should be advised immediately of the situation and of the recommendations of the officers that all 17 PPP1 projects be closed with effect from the following Monday 11th April 2016.