The Department of Education has appointed contractors to begin detailed structural investigations into 22 school buildings, all constructed by Northern Irish company Western Building Systems in recent years.

The programme will begin with five schools, in Laois, Cork, Meath, and Dublin.

The move follows the conclusion of initial assessments that were carried out on 42 schools affected by the structural defects controversy.

This second phase of examinations will determine what work may need to be done to address the problems that have been discovered.

The first five schools to be investigated are; Presentation Convent National School in Portarlington, Carrigaline ETNS, Scoil Chaitlin Maude in Tallaght, Gaelscoil Eiscir Riada in Lucan and St Paul's National School in Ratoath.

According to previous communications from the Department the structural problems have to do with faults that make parts of the schools' internal and external walls unsafe.

The company John Sisk and Sons has been appointed to conduct opening-up and testing work. Another company, Arup, has been contracted to carry out the investigations and to design solutions.

The work will take place at weekends to prevent disruption to the schools.

The Department says a schedule for detailed examination of the remainder of the 22 schools will be finalised when assessments of the first five are completed.

In a statement the Department said the focus would "initially" be on the 22 schools which had temporary measures such as scaffolding put in place in recent months to protect pupils and staff.

It says detailed building investigations will be carried out at an additional 20 schools also built by Western Building Systems during this year's summer break.