Williamsburgh Court, which is home to 89 Renfrewshire Council tenants, has new double glazed windows, a new pitched roof, new entrance vestibule, balcony enclosures for all flats and thermal cladding.
The work is in addition to the internal upgrading of the flats carried out in 2012.
The latest improvements are part of a £17.5m programme to revamp nine of the council's multi-storey blocks.
Gallowhill Court and Glencairn Court in Gallowhill have already been regenerated and are now fully let and work is beginning on four blocks in the Charleston area of Paisley.
Work is also due to begin on Speirsfield Court and Camphill Court in Paisley in the coming months.
Tommy Williams, convener of the council's housing and community safety policy board, said: "This is another major investment in the homes of Renfrewshire Council tenants.
"Over the last few years we have undertaken massive improvements to our housing stock both inside and out making people's homes more modern, comfortable and energy efficient.
"Williamsburg Court has been transformed and brought up to an excellent standard for those who live there.
"We are delighted with the outcome and have had a really positive reaction from our tenants."
Robert Moore, chairman of the Williamsburgh Court tenants and residents association, said: "It is a major improvement since before the work began. It is like night and day.
"There was some inevitable disruption while the work was done but it was worth it and we hope the tenants will be happy with the outcome."