The final Mass at the Redemptorist congregation’s Marianella centre in Dublin’s Rathgar takes place tomorrow morning.
The Marianella seminary, church and grounds, on 3.28 hectares (8.11 acres), were sold to Cairn Homes last June for €43 million.
The site at Orwell Road is expected to accommodate 280 homes, most of them apartments, on the largest site in Dublin to have come on the market in more than a decade.
The Redemptorist congregation, which has been at Marianella since 1919, announced in 2007 it planned to sell part of the grounds and build a smaller monastery there.
It secured planning approval until November 2017 for a development of apartments and houses. More than a quarter of the site was to be set aside for a monastery but that is no longer required due to falling vocations. The congregation intends using the money to promote its work in Ireland and for missions overseas.
Announcing the sale last April, the Redemptorists said: "Like most religious orders we are confronted by a future with fewer vocations, and our communities are home to predominantly elderly confreres who are in need of support and care."
The sale "will not affect our present commitments to the Dublin parishes of Most Holy Sacrament in Cherry Orchard and Assumption in Ballyfermot". It also has communities in Belfast, Dundalk, Limerick, Cork and Esker in Co Galway.
