Harris Academy could be demolished and a new school built on the site at a cost of more than £30m, rather than the major refurbishment that had been planned.
The city council’s education committee will next week be asked to investigate two options: transform the building or knock it down and build anew.
The cheaper option would be constructing a new school.
That is put at £31.25m, while the transformation is estimated to cost between £3m and £6m more.
Just under £21m of the cost of building a new school, two thirds of the total expenditure, would be met by the Scottish Government with the remaining £10.4m coming from the council.
Education director Jim Collins, in a report, stated the option of building a new school was regarded as more efficient and one which would deliver a school that met all of the educational, social and access requirements.
“The same could not be said of the transformation option, which was always a compromise between achieving the required educational, social and access requirements and retaining some or all of the 1930s building,” he stated.
“In addition, the more of the 1930s building that is retained, the higher will be the projected construction costs.”
The existing school is a category B-listed building and Mr Collins said it would be necessary for Historic Scotland to modify or withdraw the listing in order to be able to proceed with either the transformation or new build options.
Mr Collins said it was likely that a start on site could be made by the autumn of 2013.