Facade Type: Stainless Steel Cladding | Architects: Eric Parry | Location: London, United Kingdom
Aldermanbury Square is an 18 storey office building located in the City of London, next to London Wall. Designed by Architect Eric Parry, it was completed in 2007 and has been nominated for the Stirling Prize in 2009. Despite its location among the tallest office buildings in London, it is visible and easily noticed from many city angles.
The facade is set out on a simple regular grid and all emphasis is given to the cladding material. Due to a metallic skin made of shot peened stainless steel, the building has a striking appearance. The facade is reflecting the sky and the city and is slightly changing its colour depending on the weather and on sun’s position in the sky.
Shot peening is a cold working process used to prolong the life of metals through modifying their mechanical properties. It entails impacting the surface with small spherical shot particles (metallic, glass or ceramic) and makes the engineered metal become stronger and more resistant to fatigue failures and cracking.
Shot peening also has many aesthetic benefits. It creates a subtle, uniform finish enabling reflectivity to be reduced.
The concrete columns behind the facade are clad with shot peened stainless steel, and in between every two columns, an equally spaced vertical element, also clad in shot peened stainless steel, was added. This acts as a solar baffle and has the role to brake the facade into tall multi storey bays accentuating verticality and giving the facade a repetitive rhythm.
In order to give the building a slender appearance and accentuate verticality, horizontal lines are treated in a discreet manner. Every two storeys there is a dominant horizontal line, clad in shot peened stainless steel, and every other storey the horizontals are softened by introducing a slim band of stainless steel brise soleils.