Bloomberg's new headquarters in the heart of London with façade construction by seele.


steel-and-glass roof


bent glass balustrades


multipurpose room out of timber and glass panes

bloomberg's new headquarters with various construction elements made by seele

Bloomberg LP has built a European headquarters befitting its status in the heart of London. Foster + Partners designed a complex with two buildings housing offices for up to 4,600 staff, public zones, a 250-seat auditorium, 18 restaurants and a new entrance to the Bank underground station. The buildings have been designed to the latest standards regarding sustainability − a “breathing building” concept certified as “outstanding” according to the BREEAM green building rating system. Both façade and atrium roof are integrated into the ventilation concept of the complex.

  • seele was appointed to implement three challenging packages: the 335sqm roof system, the interior façade to the multipurpose room and 490m of balustrades in bent toughened safety glass. The roof system with its many components enables specific ventilation for the atrium and natural lighting for the interior. The 335sqm roof structure consists of mainly triangular insulating glass units with glass beams and aluminium sections attached with adhesive.

    The 180sqm multipurpose room is formed by solid glued laminated timber members and complex trapezoidal panes of glass. The architects specified northern red oak from America for the glulam members, which had to comply with the stipulations of FSC certification. In order to achieve the high production quality required for the glulam members, every single one was designed in 3D and the data sent directly to a five-axis CNC machine for processing. seele’s implementation concept satisfied the high demands regarding the complex details and the stipulations regarding sustainability. It was crucial that the puristic glass look be maintained for the glass balustrades. Each balustrade is supported along the bottom edge of the glass, with horizontal loads being carried by an adhesive joint in structural glazing quality between the stainless steel and glass. The design work was backed up by intensive testing.

    Reference overview and header image: © Nigel Young / Foster + Partners

  • The 335sqm roof structure of the Bloomberg headquarters in London consists of triangular insulating glass units with glass beams and aluminium sections attached with adhesive.
The 335sqm roof structure of the Bloomberg headquarters in London consists of triangular insulating glass units with glass beams and aluminium sections attached with adhesive.
© James Newton
© Nigel Young / Foster + Partners
© Nigel Young / Foster + Partners

The multifunctional roof and multipurpose room

Adhering to the “breathing building” concept of the design, seele conceived the roof as a multifunctional solution suitable for specific ventilation of the atrium and for allowing plenty of daylight into the interior. The multi-component system consists of mainly triangular glass infill panels: 13 triangles consisting of two panes of glass with a side length of 6m plus another 15 smaller triangles and nine trapeziums. Aluminium sections attached with structural glazing adhesive form the interface to the loadbearing structure on all sides of the panes of glass. A loadbearing assembly serves for drainage and ventilation. Along the outer edges of the, in total, 37 glass panes, there are 236 aluminium ventilation flaps that allow the air flowing in through the façade to escape again via the atrium roof. The side panels with the ventilation flaps were supplied pre-assembled to speed up the work on site. seele demonstrated its brilliant technical concept behind this roof solution through the geometrical detailed design for optimum exhaust-air flows and the implementation of the strict blast-resistance criteria for the design, including the glazing.

Two different types of glass were used: insulating glass for the roof infill panels and five-ply laminated glass for the beams. Louvres with 34 ventilation elements behind them were fitted below the roof around the perimeter. © James Newton
The 127 glued laminated timber members (60cbm timber) were designed in 3D in order to achieve especially precise results, e.g. for the cut-outs for the loudspeakers.
The special 3D geometry of the room acoustics called for alternating glass and timber plus an offset arrangement over 7m height on two different levels.
Puristic design: The balustrades consist of 243 bent glass panes, 40t of steel and 480m of handrail, and extend from the second to the eighth floors. Each balustrade is supported along its bottom edge. Fixing is achieved via two stainless steel sections attached with structural silicone adhesive.
A mock-up undergoing a watertightness test at seele’s own testing grounds. Water was sprayed directly onto the system developed by seele to check the drainage. A total of 380m of guttering was installed.


Client Bloomberg LP
General contractor Sir Robert McAlpine
Architect Foster + Partners
Date of completion 2017
Scope of seele supply
  • Detailed design, production and erection of 335sqm steel-and-glass roof
  • 490m of bent glass balustrades and 100sqm of screens made from 2- and 3-ply laminated safety glass and stainless steel
  • Design and construction of interior façade for multi-purpose room extending over 2 floors, with glulam members and 180sqm of 2-ply laminated safety glass

"World's highest BREEAM-rated major office building"