The FCA moved out of 25 North Colonnade to new premises on the Olympic Park in Stratford in the summer and now the building’s owner, Blackstone Group, has commissioned a makeover.
Under the contract, ISG will refurbish and develop the existing ground and lower ground floors as well as 15 upper storeys.
ISG saw off competition from BAM Construction and Sir Robert McAlpine, who were also in the frame for the contract.
The 33,425 sq m (359,800 sq ft) was originally designed by architect Troughton McAslan. Gensler Architecture has designed the refurbishment.