Germany is widely regarded as a showcase for facade technology, although a surprisingly large contribution of expertise to the current stock of futuristic projects has come from elsewhere in Europe. Nonetheless, to develop a cladding system that is lauded as sophisticated in Germany takes some doing. Italian curtain wall manufacturer SPS (www.sps.it) and German design firm Schweger and Partner succeeded in doing just that in Frankfurt earlier this year on the tightly curved facade of the Helaba Headquarters Tower, Europe’s second tallest building.
SPS, one of the few internationally-active specialists, supplied the external skin of the tower, which combines motorised sun-tracking shades with a unique opening window ventilation system designed specially for skyscrapers. Opening is automatically regulated according to climatic conditions. At the press of a button, the windows can be opened outwards up to 200mm horizontally. But in very low temperatures, rain or strong wind, the windows close automatically and cannot be opened.
The skin took two years to develop. It consists of two single panes, each 10mm thick. The sides are vacuum-coated with metal-oxide and the space between the panes filled with the inert gas krypton, which allows it to fulfil the highest European standards for sound and heat protection. The main tower uses 20% less power than conventional facades and plant – a huge saving.
The clear tempered float glass panes for the Helaba Tower were prepared by Sunglass (www.sunglass.it), also no stranger to glass bending feats. The company developed the glazed capsules for Marks/Barfield’s London Eye. The 8m x 4m pods are designed for 360º visibility, and each contains 11 different designs of laminated safety glass pane, produced with 14 bending moulds. Amazingly, the company supplied the panes in 141 days.
Another Italian cladding manufacturer made its mark in Bavaria last year when Focchi (www.focchi.it) developed the Radiant Facade, an off-the-peg take on the hypersurface trend, for Massimiliano Fuksas’ Salzburg Europark Shopping Centre, Austria. The reconciliation of commercial architecture and socio-cultural ethics has long been one of Fuksas’ chief concerns.
An out-of-town business park site with little discernible context has spawned one of the architect’s favourite works. He designed the Europark ‘proceeding in sections from the inside to the outside’, treating the facade as the grand finale. And grand it is – characterised by a double-skin with the EUROPARK logo fritted white on blue glass and illuminated spectacularly at night.
The first skin acts as a thermal break system, which assures, through structural silicone technology, a homogeneous external surface which conceals the opening and fixed parts beneath. The uniformity of the exterior skin is essential for the realisation of the logo, which is made up of letters 9m high and 4m wide.
The second skin is a pane of fritted glass anchored by aluminium fusion to the external skin. Double fritting on the outside of the first skin and on the inside of the second gives the logo its depth, with the lighting located in the cavity of the double-skin. All the mechanisms and the ironmongery of the smoke exhaust are concealed.
Focchi has also just finished the spectacular bullet-proof suspended glazing system for Renzo Piano’s long-awaited Banco Populare di Lodi.
The elegant terracotta and glass facade and gravity- defying suspended concourse canopy have drawn gasps of wonder from newly installed staff.
Schüco (www.shueco.de) continues to forge ahead in the eco-facade niche, pushing its Synergy Facade into the commercial marketplace. Schuco has been producing solar facades for many years, but the Synergy Facade first hit the headlines in 1998 when it was specified for Studio E Architects’ Solar Office at Doxford.
Okalux (www.okalux.de) has a different approach to energy management. Its Okalux light diffusing and hermetically sealed glass incorporates a unique translucent capillary honeycomb structure within the cavity which can reduce a building’s cooling load by up to 30%. Louvre fittings increase the system’s effectiveness, as demonstrated by Pysall-Starrenberg & Partner’s 500sqm Nord LB glazed biosphere dome in Braunschweig.
But the cladding innovation hasn’t been entirely exclusive to Europe. American projects were conspicuous in the 2000 DuPont Benedictus Awards for innovation in laminated glass, sponsored by a German firm and historically favouring west-European entrants. Second place in the prestigious commercial sector went to Eric Owen Moss and California Glass Bending’s (www.calglassbending. com) Umbrella. The dramatically undulating curved panes for the project’s glass canopy have long been considered a technical impossibility.
It could be argued that the Umbrella isn’t strictly a cladding achievement, but the significance of the breakthrough in glass manufacture will have repercussions in the industry. Each unique panel was formed by slumping two sheets of tempered glass over a steel mould, then laminating them with polyvinyl butrayal before using pressurised steam to bind them together. Many panels were broken in the trial-by-error production process, not least when the complex hanging brackets were wrongly aligned.
The canopy covers an amphitheatre, as part of a mixed use public project in the deprived California suburb of Culver City. It is defined by a 14-inch diameter steel pipe which terminates the vaulted bowstring roof. The result has seen Moss and his team labelled ‘alchemists’ in the press, perhaps for doing for glass what Frank Gehry did for titanium cladding.
Fougeron Architecture’s 500sq m 440 Residence in Palo Alto, California took first place in Dupont’s residential category. The project uses glass liberally to articulate the circulation spine, through laminated glass floors and a sandblasted glass bridge, both of which accentuate a spectacular glass-clad stair tower penetrating the building’s skin. California manufacturer NGA Glass (www.nga.org) supplied the project.
First place in the student category also went to an American – Robbie Forslund’s concept design for teaching buildings at Oklahoma State University included a cladding system comprising 120 individually operable glass panels.
Back in Germany, where new facade materials and ideas appear to have the best chance of seeing the light of day, UK engineer Buro Happold and Japanese architect Shigeru Ban were responsible for the cardboard-clad Japanese pavilion – the talk of the Hanover Expo. The 35m clear span structure is constructed from a core of paper tubes clad with lightweight paper and polymer coated polyester membranes.
Japanese firms, more familiar with Ban’s ideas on material sustainability than energy-obsessed Europeans, supplied the majority of the components. The TSP Taiyo-manufactured paper membrane (www.nittenkyo.ne.jp) required support on a 3m grid, and had to be lifted clear of Sonoco’s paper tubes (www.sonoco.com) to avoid moisture being trapped against them. Timber ladders were introduced to generate a series of gutters and to provide a simple means of attaching the paper membrane.
The manufacturing process of the paper tubes is very simple – recycled paper is pulled out from a paper roll cassette, put into a jar filled with glue, rolled again in a spiral by a winder and cut into pieces of a designated length. The constituent parts of the paper system have yet to be sold as a package, but an off the peg paper system would be both cheap and lightweight, and have interesting implications for builders of fixed-life buildings.
Also at Hanover, Skyspan’s (www.skyspan.com) 10 giant Hermes Umbrellas also pointed to the future in PTFE glass fabric cladding. A specially designed framework attachment connects fabric to a monocoque wooden grid, set at a height of 20m above the ground.
The connection technology, developed by Skyspan along with Thomas Herzog, breaks new ground, allowing vast areas of membrane to be erected with little visible support.
Source
World Architecture
