Wates Construction is returning to the 41 Lothbury site 18 years after completing a previous overhaul of the building.
The 130,000 sq ft office building was originally built to serve as the headquarters for Natwest Bank.
The Edwardian building features heritage assets including iconic stone columns, an original checkerboard marble floor and a grand central atrium.
The programme of work will transform existing rooftop space on floor seven and introduce an eighth floor with new outdoor terraces offering spectacular City skyline views.
The iconic Banking Hall will also receive a fresh injection of high-quality finishes including a new hospitality-style reception, agile breakout spaces and an impressive entrance with statement lighting and artwork by internationally renowned designer, Jason Bruges.
Architect, Stiff + Treviliion will work with Wates to target BREEAM Excellent, Wired Platinum and NABERS sustainability and well being benchmarks.
Phil Shortman, regional managing director, Wates Construction London, said: “It is an honour to be selected as Pembroke’s trusted partner of choice and return to 41 Lothbury to cement this historic building’s future for the next generation of city workers.”