Architect Kohn Pedersen Fox to replace interior and restore stone exterior of listed office block in central London

Unilever鈥檚 imposing stone headquarters overlooking London鈥檚 Blackfriars Bridge is being radically reconfigured to bring the corporation鈥檚 working practices into the 21st century.

By early 2007, if all goes to plan, the congested interior of the 1930s sub-classical Unilever House will be replaced, and its listed stone exterior restored. In this way, the 拢90m project resembles the transformation of the Treasury鈥檚 headquarters in Whitehall. And on both projects, Stanhope was the development agent with Bovis Lend Lease as the construction manager. The architect for the refurbishment is Kohn Pedersen Fox; Arup is structural and services engineer.

About 42% of the floor area of the original building, including two narrow wings at the rear, has been demolished. This has allowed the floorplates along the two street frontages to be widened from 13 m to 19 m and a large atrium to be built in the triangular space between them. In addition, the rooftop plant is being moved to the basement, allowing the ninth floor to be converted into meeting rooms with river vistas.

鈥淲e wanted to bring coherence and legibility to the building,鈥� said KPF director John Bushell. 鈥淲e will end up with slightly less gross floor area but vastly improved space efficiency.鈥�

The main entrance is being shifted from the corner to its original location at the centre of the riverfront facade, where it leads into the heart of the new atrium. From the corner and along the side street, the ground floor will be converted into a public gallery for the company, along with a cafe and restaurant. The basement is being converted into a staff fitness centre.

All existing lift and stair cores, which were dispersed through the building, have been removed. They will be replaced by four structural lift and service cores located where the atrium adjoins the old floorplates.

At the base of each lift core, three caissons have been hand-dug to a width of 3 m and depth of 25 m. The lift cores support the atrium structure and reduce the number of holes to be cut through the thick concrete basement slab.

Externally, roof clutter including the fibreglass statues are being removed to give a clear roofline when viewed across the river.