Assessments have now been carried out on half of the schools around the country at the centre of concerns over structural deficiencies.

The Department of Education has said that 21 of the 42 buildings have so far been inspected by engineers.

It was confirmed today that another school, Castlemills Education Centre in Balbriggan, will require some external remedial work but it will not result in the closure of the premises.

A fence will be installed around the building during the mid-term break.

Similar work will be carried out at Scoil Chaitlín Maude in Tallaght.

Efforts are already under way to source temporary off-site accommodation for a number of classes at Tyrrelstown Educate Together National School, St Luke's National School also in Tyrrelstown and Gaelscoil Eiscir Riada in Lucan, where parts of the buildings will be closed for a time while repair work is carried out.

Six schools - Luttrellstown Community College, Gaelscoil Shliabh Rua in Sandyford, Broombridge Educate Together National School, Scoil Choilm in Porterstown, Gaelscoil Thulach na nÓg in Dunboyne and Gaelscoil Teach Giúise in Firhouse - require no intervention and classes will continue as normal.

The inspection work from nine other schools is still being assessed.

Arrangements have already been put in place to accommodate students at Ardgillan Community College in Balbriggan, where issues were first detected, resulting in the closure of a section of the school.

The schools being assessed were built by Western Building Systems over the last decade.

The company has welcomed that 21 of the 42 schools identified by the Department of Education have now been assessed.

In a statement, the Co Tyrone-based company said it "appreciates fully that this is an important matter, particularly for pupils, parents and teachers."

Western Building Systems said it is "committed to better understanding why schools previously certified for completion by the Department are now being assessed by the Department."

The company said it has been engaging constructively with the Department of Education over the past number of days, in accordance with its contractual obligations, and added that it immediately offered to participate in the assessment process. 

Western Building Systems also said it remains available to meet with the Minister for Education and Skills.

The company has defended the work it has carried out.

A spokesperson for the Department of Education has said engineers are on track to complete the structural inspections on all of the 42 schools by the end of the mid-term break.

A further update will be issued tomorrow.