The 40 Leadenhall office project gained planning over four years ago but has been on hold while financing is put in place.
Developer TH Real Estate has now sold most of its stake to a consortium of Far East investors who will proceed with the 900,000 sq ft scheme, where Keltbray is carrying out demolition.
The win lifted Mace from 12th in the annualised rankings to 8th, according to data compiled by construction information specialist Glenigan,
On a 12 month rolling basis Kier nudged Sir Robert McAlpine form lead last month after landing a £45m student accommodation scheme for the University of Warwick.
CRH, which now includes order books of both Farrans and Alun Griffiths Contracting, came out top for civil engineering orders in February with Balfour Beatty retaining its place on top of the 12 month rolling league.
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Among the other big building wins Graham Construction secured an £86m residential scheme in Liverpool for Patten Properties.