The building of a new school complex on the former Greenhead High School site has been hit by delays.

The new University Academy Keighley campus was due to open next April, next to the existing school buildings. Beechliffe School, which will replace Braithwaite and Branshaw special schools, was due to open alongside.

Education chiefs this week revealed that due to blunders last winter by constructors, the opening date could be postponed.

Bradford Council refused to reveal the new date on the grounds that the information was “commercially and legally sensitive”. Revised dates have also been drawn up for three other schools, Beckfoot School, in Bingley, and Hanson School and Grange Technology College, in Bradford.

The delay is a knock-on effect of problems which last winter hit construction of the four mainstream schools along with four co-located schools for teenagers with special educational needs.

Major damage occurred to concrete floors at each of the sites after water left in under-floor heating pipes froze when temperatures plummeted last December.

A report on the matter was considered by the council’s children’s services overview and scrutiny committee on Tuesday. The report confirms that the damage has delayed the construction programme, meaning the scheduled hand-over dates for the new buildings will not be met.

The report says: “Revised programmes have been provided by EduCo through the LEP (Local Education Partnership) which indicate varying but later dates for hand-over of the campus sites.

“The implications of these dates on the transfer of schools into the four new campus site buildings are currently being worked through with the schools to ensure minimal impact on education.” EduCo — a consortium of construction giants Costain and Ferrovial Agroman, two firms involved in Integrated Bradford, the local education partnership — has spent more than £600,000 repairing the damage.

EduCo is responsible for Bradford’s Schools for the Future design and building work.

The council confirmed the damage occurred after contractors filled the heating systems with water to test for leaks and failed to drain them before they were covered in the concrete.

Since then, on-site working hours have been extended at each school, with builders working late at night and through weekends and bank holidays in an attempt to stick to the original timescales.

Five months ago, Integrated Bradford’s general manager, Tony Smith, said all affected schools were back on track for completion by the original contract dates.

But Kath Tunstall, the council’s strategic director for services to children and young people, admitted consultation was being carried out to plan for the possibility that the dates would slip.

She said: “The local authority has been informed by Integrated Bradford, the company which manages the Building Schools for the Future programme in Bradford, that as a result of the inclement weather suffered last winter the construction programme for the phase two secondary and secondary special schools could be delayed. The local authority is not yet able to confirm the date on which the schools will move into their new facilities.

“The authority, the chairmen of governors and the head teachers are working with Integrated Bradford with the aim of minimising any delay to the programme and to ensure that, on a site by site basis, the schools are complete and able to operate as soon as possible.”