Developers in London are revamping office spaces to suit the post-pandemic workforce, a survey showed on Monday, as weakening demand for workspaces poses a major concern in one of the world’s biggest financial hubs.

New construction starts have jumped by a fifth in the six months ended March to 3.1 million square feet, Deloitte's London Office Crane Survey showed, with 56% of the pipeline expected to involve an extensive upgrade of existing office stock.

Lockdowns, since early last year has forced millions of people to work from home, but easing restrictions, are driving companies to chart a return with less hot-desking, more room, and better health regulations.

"Occupiers' needs are shifting and buildings that meet their ESG principles while taking into account the welfare of their people are top of mind. Grade A, well-connected and eco-friendly office spaces, designed to maximize the benefits of new ways of working, will be the most desirable," said Mike Cracknell, director in real estate at Deloitte.

The survey showed 4.5 million square feet of development has been delivered between October 2020 and March 2021, the highest level of completion in 18 years. In a sign of less speculative building, 59% of that was pre-let.

The survey also showed that the share of Technology, Media and Telecoms (TMT) pre-lets in all space under construction increased to 40%, reaffirming the importance of the TMT sector in the London leasing market.

Still, many companies have embraced work-from-home as a cost-effective and flexible option that is here to stay, hurting demand for workspaces in London.

The city’s developers anticipate new working patterns to reduce office demand on average by 10% to 15% in terms of square footage.