In keeping with the renown that Citibank enjoys worldwide, the bank's new headquarters building in Bahrain was required to be built to exceptional standards. The designers, therefore, turned to Swiss specialist Schmidlin AG, to carry out the customised glazed facades by which the building is recognised, says an Abu-Dhabi-based executive for the company.

"Gracious curving facades, cut by an oblique bay window, an imposing entrance hall in the form of an atrium, bold horizontal features and extensive fritted glass - the specification had it all and Schmidlin delivered, on time, in budget," comments Roger Schaerer, general manager of Schmidlin AG Emirates.

Amongst the many interesting features of the building are large areas of glass rendered partially obscure with extensive ceramic frit patterns, avoiding the need for additional shading, while in the atrium area, air-conditioning is supplied through carefully designed and concealed aluminium grilles disguising the source and eliminating ductwork, he says.

Schaerer continues: "The elliptical entrance hall, some three storeys high, is fully glazed in the feature glass with a teardrop-shaped spider system glass roof - which is essentially a frameless laminated and point-fixed glass roof. Access to the building is via stainless steel and glass security doors on concealed floor-mounted electric operators, embodying the theme of modernity with security."

To ensure that the curtain-walling can withstand the region's harsh climatic conditions, it was put through a number of tests

Schaerer elaborates: "The extreme weather of the region is known to expose the weakness of any material. So extensive and rigorous testing was undertaken on mock-ups in a laboratory-controlled environment to push the design to the limit. International testing standards set limits for air and water infiltration, wind resistance and structural safety and each design passed the test. Tests were conducted for air-permeability, watertightness, wind resistance, thermal cycling and on-site water hose test all in accordance with AAMA and CWCT specifications.

"Buffeting from an aeroplane engine while being drenched by water at high pressure is certainly proof of the facade's wet weather resistance. However, the facade was also subjected to extreme thermal testing for temperatures that are prevalent in the Gulf. This tested the system's ability to cope with expansion and contraction. To further confirm this, the mock-up was drenched again, and again passed the test."

The curtain-wall has a U-value of 1.5 W/sq m/K. The exterior profiles are coated with PVDF2 while the interior ones are power coated. Parsol Green tinted glass from Pilkington has been used for the project.

"The Schmidlin quality system, registered to conform to ISO 9001, and attention to detail have produced engineered solutions to the complex architectural challenges of the project," he adds.

Switzerland-headquartered Schmidlin AG, which was founded in 1936, is now one of Europe's leading and largest companies in design, engineering, manufacturing, supply and installation of high-quality windows and curtain-walling.

It claims to be the first Swiss curtain-wall manufacturer certified with ISO 9001 / EN 29001.

The company says it offers service and support in every phase of a project including pre-tender technical sales advice, budget pricing, tendering, sub-contract design, engineering, manufacture, supply and installation of partial and total, regular and integrated facades, atriums and entrances.

Schmidlin's international team of designers and project managers, experienced fabricators and quality audited suppliers are creating landmark projects for corporate clients worldwide and operate from strategic facilities in Basel (Switzerland), London (UK), Berlin (Germany), Paris (France) and Abu Dhabi.

Other recent projects in the Schmidlin portfolio: