The original school building was constructed of cut stone on the grounds of St. Johns Cathedral complimenting both the cathedral itself and the presbytery.
The funding for this building was donated by Dr. Robert Frith, a medical doctor who practiced in Limerick between the years 1835 until his death on 21st November 1867. Seeing the need to improve the organisation of education in the Garryowen area Dr. Frith initiated the building of a school for young girls in 1858. Later Dr. Frith left money for a boys wing which was added in 1893.
Administered by the Sisters of Mercy, the original school operated for the next 100 years until it was blown up by the army and replaced by a modern structure in the early 1970's. This building was used until it's refurbishment in 2007/08.