The Sihlpost: Zurich’s landmark building with a brand new interior

With its clock tower that can be seen from afar, close to the main railway station, Zurich’s main postal building, the “Sihlpost”, is a historical landmark of the city.

Built in the style of the “new building” era, the 123-metre long rectangular building was regarded as the most modern postal office in the world when it was completed in 1930.

As the building’s owner, the Swiss Federal Railways (SBB) invested 45 million Swiss francs into a comprehensive renovation. Under the direction of Max Dudler Architekten AG, the building was adapted to the most modern building standards.

Today, the listed building presents itself not only as a post office. Completely renovated in the interior and with a new exterior façade, it serves as a modern townhouse for trade, gastronomy, business and education.

GEZE contributes with modern multifunctional door automation and safety technology to safe and comfortable building use.

The imposing façade of the building is dominated by three large glass portals as access points to the switchboard and the separate locker area.

Fine-framed for maximum transparency while being optically discreet, the two-leaf glass sliding doors – nearly 300 cm high and 320 cm in width – have power, performance and safety in the façade and the vestibules: they offer self-evident accessibility, a safe escape route and increased burglary resistance.

The Slimdrive SL-FR drive systems ensure “clear passage” in escape and rescue route doors in the event of danger. Modern, intelligent control technology conceals itself in the discreet Slimdrive control units in "70-millimeter optics" that is typical to GEZE.

The time the doors remain open adapts to the frequency of through traffic. If the visitor flow increases, the door leaves are automatically kept open for longer. The movement parameters (acceleration, hold-open time, and opening and closing speed) may be set individually.

The control of the Slimdrive drives makes the doors future-proof and makes system integration into building control technology possible, so that monitoring or changing door functions can also be carried out remotely.

When it gets tight: maximum opening widths

With the new design of the Sihlpost building, now used by even more people than before, a direct access to the KV Zurich Business School was created via the newly named Sihlpostgasse.

In the limited building opening, a maximum opening width of 250 cm was achieved with a four-leaf automatic telescopic sliding door system with specific Slimdrive SLT drive systems, designed as emergency exits.

The "parking" of the door leaves is not a problem with this solution. Fanlights enable the maximum use of daylight.

Safety and efficiency in the service areas

The tested quality of the GEZE solutions for fire protection doors as fire barriers was chosen in the basement of the traditional vegetarian restaurant, Hiltl, with fully automatic sliding door solutions of fire resistance class EI30.

They ensure an enclosed space in the event of fire, smoke or heat. Light and almost silent, a particularly powerful Powerdrive PL drive moves the large, heavy and wide opening metal sliding door to the storage area.

With Slimdrive SL NT drives, a two-leaf metal sliding door with viewing windows overcomes the permanent "on and off" of the service personnel in the restaurant kitchen, in a barrier-free, safe manner, quickly and quietly.

In accordance with their function as fire barriers, these doors close in the event of a power failure using pre-stored energy. Therefore the closing function continues to be ensured even if there is a fire.

In the event of fire, the doors close automatically, providing a secure fire barrier – even if the hold-open function of the automatic door was previously in use.