The developer said that while a number of speculative developments started as expected during the quarter, the supply of available space remains low.

Against this background Derwent said it remained confident with the scale of its current development programme and the prospects for the three new schemes with a total floor space of nearly 700,000 sq ft.

The projects include Derwent’s new concept office scheme (below), known as the white collar factory at Old Street.

A prototype of the interior design has been completed near the site and marketing presentations will begin in June.

Derwent has brought forward the building programme and now expects to start construction of the 289,000 sq ft building on a speculative basis in early 2014.

The island site adjoins the Old Street roundabout in the heart of ‘London’s Tech Belt’ and completion of this energy-efficient scheme is expected in the second half of 2016.

The stripped down interior specification will help to reduce construction costs in the more competitive London office market. Derwent said it hoped to achieve a targeted build costs of around £180/m2.

Derwent is also advancing plans for a 385,000 sq ft office and residential scheme at 80 Charlotte Street.

This involves part demolition and refurbishment of the existing Saatchi & Saatchi offices into an office-led mixed-use development. The project will create additional floor space by infilling the existing courtyard and car park, with additional floors at roof level.

Architect Make’s designs have been finalised and the construction contract is out to tender with BAM Construct, Brookfield Multiplex and Mace.

Another smaller office and residential scheme will also start at 70 Charlotte Street of around 15,000 sq ft.

The projects at Charlotte Street and the White Collar Factory will more than double the area of schemes under construction in the next 12 months.