While office developments in the capital remained flat in the second half, the survey showed “a marked increase” in space under construction in the City.
Nine new schemes kicked off in the period, totalling 4.1m square feet – up 15 per cent on six months ago. It is also the first time construction has broken the 4m sq ft mark since 2009.
The increase is in stark contrast to construction output in the rest of the country, where the sector is in decline.
But while City building levels increased, completion levels remain low after developers delayed schemes in 2009 and 2010.
Matthew Elliott, partner and head of City agency, said while banks, which have been slashing their workforce, have been reluctant to move, the insurance sector has been taking up space.
“As banks retrench so insurers are boldly moving into new buildings and paying high rents,” Elliott said.
He added that the City is also luring a more diverse tenant base, with several tech and media firms attracted “by the low cost and high quality of the buildings on offer”.
Construction levels across Central London remained flat at 9m sq ft.