The Department of Education and Skills is suing a firm over alleged defects in a €5m "rapid build" school which had to be closed for part of a term last year for repairs costing €1m.
The Tyrrelstown Educate Together National School in west Dublin was one of two schools shut last year after safety inspections for the department.
The other was Ardgillan Community College in Balbriggan, north Dublin.
Last December, the department brought proceedings in the Commercial Court against Western Building Systems (WBS) of Coalisland, Co Tyrone, which designed and built Ardgillan.
Yesterday, the department brought similar proceedings against WBS in relation to Tyrrelstown which were also entered into the fast track commercial list by Mr Justice Robert Haughton.
The department says the 525 Tyrrelstown pupils had to be moved to alternative accommodation nearby from the mid-term break in October until after the Christmas holidays.
This was to allow temporary remedial works to be carried out to the school building.
Those remedial works have already cost €950,000 and are likely to exceed €1m, according to the department.
It added that the final cost of permanent works is not yet known.
Tyrrelstown was designed and built under a 2011 "rapid build school delivery" contract for just over €5m between the department and WBS.
Eamonn Murtagh, principal officer in the department, said the building did not comply with fire certificate and/or building regulations and/or with the department's build requirements.
He said a consulting engineers' report found issues with the strength and fixity of the walls panels in the building.
This gave rise to a risk of a collapse "fall out" of the outer masonry wall panel and the "fall in" of timber infill panels into the classrooms.
In its action, the department seeks damages for breach of contract, negligence and or misrepresentation by WBS arising from the design and/or construction of the school.
Mr Justice Haughton, after admitting the case to the Commercial Court on consent between the parties, adjourned the matter to July.