Complex curved concert facade

Located on the Elbe River in Hamburg, Germany, the Elbphilharmonie is one of the largest and most acoustically advanced concert halls in the world and an outstanding example of modern architecture.
Designed by Herzog & de Meuron, the building is a residential and cultural complex. The 108m-high building, which officially opened in January 2017, accommodates a philharmonic hall, a chamber music hall, restaurants, bars, a terrace with panoramic views of Hamburg and the harbour, luxury apartments, a hotel, fitness centre, conference rooms, and parking facilities.
The design of the new glass building resembles a hoisted sail or water wave. Extruded from the shape of the original Kaispeicher warehouse that supports it, the new glass building is identical in ground plan with the brick block of the older building, above which it rises. However, at the top and bottom, the new structure takes a very different design from the quiet, plain shape of the warehouse below.
The new building’s 21,800m2 glass facade consists in part (approximately 5,000m2) of curved glass that transforms the structure into an enormous quartz crystal, whose appearance continually changes as it catches the reflections of the sky, the water and the city lights.
Josef Gartner was responsible for developing the glass facade. It is comprised of both flat and curved insulating glass units (IGUs) for the windows, as well as triple laminated curved single glazing for the loggias (covered exterior galleries).
One of the challenges was developing the curved glass elements of the facade. Up to that time, nobody has ever bent glass panes of that complex 3-D-geometry, according to Guardian Glass.
The next challenge was to maintain the functions of the different coatings of the glass during the manufacturing process. The glazing of the facade consists of a low-e coating, a solar control coating, chrome mirror dots and a ceramic silk-screen pattern. The solar control coating and the chrome dots were vital in achieving the customers’ performance requirements. Gartner was concerned that the high temperatures in the bending oven would destroy these layers or adversely affect their performance.
“We talked with many companies, but Guardian was the only one that could offer a base layer that would guarantee that the sun protection layer maintains its functions during the manufacturing process,” Karl Lindenmaier, senior project manager at Josef Gartner, said. “In close collaboration with Guardian, we were able to achieve and maintain the customers’ requirements.”
The Guardian Glass team also worked closely with the curved glass processor, SunGlass. This ensured that the curved glass met the architect’s requirements in terms of performance and aesthetics.
Guardian ExtraClear float glass was selected as a base glass for the whole façade, thanks to its combination of transparency, aesthetics and performance.
Guardian also supplied its coated solar control glass, SunGuard Solar Light Blue 52. This product provided sufficient stability during the glass bending process, while also meeting the architect’s requirements.
In a standard insulating glass unit, SunGuard Solar Light Blue 52 provides a visible light transmission of 47%. It also has a low solar factor of 36% to help reducing demands on the building’s air conditioning and controlling the temperature inside the building. Furthermore, the SunGuard Solar Light Blue 52 coating provided the possibility of applying the ceramic silk-screen pattern directly on the coating.
Guardian also supplied its ClimaGuard DT thermally insulating coated glass. This product combines neutrality, thermal insulation, durability and easy processing. It offered a high stability during the glass bending process, while also meeting the architect’s requirements.
Guardian also provided technical support including thermal and spectrophotometric glazing calculation data, and thermal stress analyses. Using its experience and knowledge base, Guardian was also able to provide suggestions and guidance on glass bending and ceramic printing of coated glass.