09. Dec 2021

Metal fabric shell for exterior stair tower

The 'Josephinenschule' school in Chemnitz, which was founded in 1898, was legally required to construct a second fire escape route as part of a core refurbishment process. However, there was insufficient space inside the listed building to install this escape route indoors. The Chemnitz-based architecture and engineering office Bornemann therefore proposed an outdoor escape stair tower with roofing and intermediate platforms.

The architects collaborated closely with the building preservation authorities and selected GKD Tigris stainless steel fabric as an attractive cladding for the functional steel construction. The rectangular tower, which measures 19 meters in height, connects to the outside of the five-story school building. Students and teachers can use it to exit the building in the event of an emergency. Despite its size, the transparency of the metal fabric shell allows the tower to blend in visually with the building’s distinctive brick, sandstone and porphyry façade. Featuring a 61 percent open area, the fabric also guarantees natural lighting and ventilation for the escape route. Despite this, the outer shell is stable and offers reliable protection from the wind and rain.

The fact that it also satisfies the strict safety requirements of effective fall guard protection in connection with the railings was another key factor that supported the specification of this material for the shell. Five fabric panels – each measuring up to 19.2 meters long and 5.2 meters wide – enclose the stair tower. They are attached at the top and bottom using the tried and tested solution of round profiles and eyebolts. Intermediate attachment elements, produced from cable clamps attached to the circular pipes already on the building, offer additional support.

Because they are easy to install, offer a high degree of functionality and are essentially maintenance-free, GKD metal fabrics are proving ever more popular as practical and economical design options for exterior fire escape stair towers. As weather-resistant shells, they reflect sunlight and lend structures a sense of elegant lightness. Besides the Tigris fabric that is used in Chemnitz, Futura and Omega 1520 stainless steel fabrics have also proven their effectiveness in many stair tower projects.