SIPTU is to consider putting one of Dublin's landmark buildings, Liberty Hall, up for sale.
The 15-storey city centre building is in need of refurbishment and disposing of the property is one of the options to be discussed by the trade union's national executive early next year.
The union is also in discussions with its staff about a major restructuring programme that is likely to result in the closure of some of its 45 offices throughout the State.
Some of the 360 staff will be asked to relocate, but there will be no job losses.
Mr Joe O'Flynn, the union's general secretary, told The Irish Times he expected a decision on Liberty Hall to be made in the first quarter of next year.
He said the options included vacating the building for up to two years while refurbishment was carried out, and then either totally or partially re-occupying the premises.
As part of its restructuring programme, the union is considering moving some branch offices out of Liberty Hall and locating them closer to where many members work in outer areas of Dublin.
That would free up office space in Liberty Hall that the union could let out, while maintaining its headquarters in the building.
Disposing of the building entirely is another option that will be considered. Mr O'Flynn indicated this would not be his personal preference and said the decision would not be based on commercial grounds only.
"All options have to be considered, having regard to the best interests of the members and staff of the union.
That means no option is excluded, including relocating to a more modern, purpose-built building on the periphery of Dublin."
"But that's only one option and I wouldn't want anyone to think it was being forwarded ahead of others."
Any decision, he said, would have to take account of the historical significance of Liberty Hall for the trade union movement and the State.
The site has been in trade union ownership since Jim Larkin took a lease on the old Northumberland Hotel at Beresford Place for £5,500 in 1913 and renamed it Liberty Hall.
It provided soup kitchens to feed starving workers during the lockout of the same year and was bombarded during the 1916 Rising.
The original building was demolished by the Irish Transport and General Workers' Union in 1962, to make way for the present structure, which was completed in 1965.
SIPTU has had its headquarters there since 1990 when it was formed from a merger of the ITGWU and the Federated Workers' Union of Ireland, both of which were founded by Larkin.
Mr O'Flynn said the union's members and staff would be consulted in advance of any decision.
Intensive discussions with staff on a proposed restructuring of the union, to include some office closures, are to continue until the end of February.
