Rail House in Manchester's Piccadilly area is to be redeveloped by government subsidiary BRB Residuary at a cost of £25m.
The 140,000 sq ft building will be renamed Piccadilly Gate and brought up to an 'excellent' environmental BREEAM rating.
The Office of Government Commerce recently ordered the Highways Agency and Government Office for the North West to pull out of 65,000 sq ft of deals at Argent's nearby 3 Piccadilly Place. The OGC said both bodies should take space in the 1960s-built Rail House rather than new-build stock.
Sanderson Weatherall is advising BRB Residuary.