Mace has won the last major City office deal to be awarded this year putting an end to Multiplex’s series of major successes in the capital in recent months.

The firm was told earlier this week it had beaten its rival to the £200m job at 65 Gresham Street.

Multiplex’s run of victories in London this year has included 75 London Wall, the retendered ITV Studios job, a judicial decision on which is due next week, and the 50 Fenchurch Street tower.

Designed by Squire & Partners, the 65 Gresham Street job for JP Morgan Asset Management is being described as one of the largest building reuse projects in the Square Mile.

The building was originally designed by Sheppard Robson and completed in 2001 but the new plans involve expanding it from 24,995 sq m to 37,767 sq m. The proposals include adding balconies, upper level amenity space and outdoor workspace to every floor.

Others working on the deal include cost consultant Turner & Townsend Alinea, project manager Opera, structural engineer Buro Happold, services engineer Atelier 10 and facade engineer Murphy Facade Studio.

Meanwhile, Mace and Multiplex are both being sounded out on a job called the Dovetail Building in the City of London.

Designed by AHMM, the 23-storey scheme was given planning three years ago with Lendlease then brought in under a PCSA.

But Building understands that developer Brockton Everlast has others to look at pricing the job as well with bids set to go in in January at the earliest. The value of the job is thought to be around £400m.