Contractors O’Hare and McGovern, which initially began the £35 million project in November 2014, have advised that it will not be completed until October 28.

It means that pupils won’t be able to move into the school located on the bank of the Union Canal in Fountainbridge until January next year.

Youngsters were originally due to move in at the start of the new school session in August until it emerged in June last year that the opening had been delayed by two months after “challenging” foundation work slowed construction.

In a briefing note to councillors, city education officers said: “We have been advised by our contractor, OHMG, that due to the adverse weather conditions which they have experienced over the last few months, the construction work on the new school building will finish five weeks later than they had anticipated and will now not be completed until October 28, 2016.

“This was not entirely unexpected as the timing and method of construction for the new Boroughmuir is very weather dependent – high winds prevent the use of cranes to pour the concrete to the upper levels, a process which, in itself, is significantly affected by snow, rain and low temperatures, all of which we have experienced lately.

“Having gone through the programme critical path there are no remedial measures which OHMG could take to bring the completion date forward.”