Dublin City councillors have voted to seek an increase in the number of social housing units at Priory Hall to 30%.
But they have given the go ahead to the council to begin a sales campaign for the first phase of 44 reconstructed apartments at the end of the month.
Motions from left-wing parties to unilaterally make all units available for social and affordable housing were narrowly defeated.
Council chief executive Owen Keegan had warned there was a legally-binding agreement in place to sell former owner-occupier apartments privately.
He said the council could face legal action if it tried to ignore the agreement.
But he said the council could ask the financial institutions involved to increase the social housing provision from 20% to 30%.
Mr Keegan said the involvement of approved housing bodies and the Housing Purchase scheme for low income buyers could be used to increase the number of social and affordable units.
Councillors passed a Labour motion to seek an increase in social provision to 30% and for 30% affordable.
A motion from the Anti-Austerity Alliance to make all units available for social and affordable housing was tied at 24 votes for and against and only defeated by the casting vote of Labour's Lord Mayor Brendan Carr.
The original complex had 63 owner-occupier units and the agreement reached with financial institutions in 2013 provided that these would be sold to recoup money owed on the mortgages.
A further 66 units formerly owned by developer Tom McFeely were purchased by the city council from the Irish Bank Resolution Corporation on condition they were sold in the private market.
There are also 26 buy-to-let units which are still owned privately and 35 for social housing.
