Trianon Tower Frankfurt am Main
Retrofit smoke control system in high-rise use
At 186 metres, the Trianon tower in Frankfurt's Westend district is the sixth-tallest building in Germany. 66,000 square metres of rental space are spread over 47 floors, in which a large number of people work every day. To ensure their safety, fire and smoke control plays a central role. As part of an extensive refurbishment, the Arge Trianon Brandschutzsanierung consortium under the leadership of Hochtief Building GmbH carried out a complete fire protection refurbishment of the office building on Mainzer Landstraße and, among other things, brought the structural fire protection up to date. It turned out that the fire resistance doors and other fire protection closures of the building commissioned in 1993 were still in very good condition, but that they did not meet the current requirements for smoke control. Instead of replacing the doors and flaps in a laborious and cost-intensive manner, a retrofit smoke control system from System Schröders was used. Thanks to this system, the work could be carried out cost-effectively, cleanly, and quietly while the building remained in operation.
Model Building Code requires smoke control closures
The Model Building Code requires that at exits from stairwells that do not lead directly outdoors, the space between the staircase and the outside exit must have smoke control doors. The same applies to transitions from stairwells to corridors. These must also be divided into several smoke compartments with the help of the smoke control doors. In addition, the Model Building Code prescribes fire-retardant and smoke-tight closures for openings from stairwells to basement storeys, undeveloped workshops, attic rooms, shops, storage rooms, as well as other rooms and units of use with an area of more than 200 square metres. In high-rise buildings, the vertical service shafts are also considered particularly critical. If the smoke control in the form of appropriate flaps is insufficient here, toxic gases spread rapidly across all floors.
Requirements for smoke control closures
Smoke control doors and flaps are building elements that, in the installed and closed state, impede the passage of smoke for a certain period of time. Their use is legally regulated in the building codes of the German federal states; the requirements for the closures are defined by DIN 18095. They must close automatically and impede the passage of smoke at temperatures of up to 200 degrees. For single-leaf doors and flaps, the maximum permissible leakage rate at 50 Pascal pressure differential is 20 cubic metres per hour, for double-leaf doors 30. In the tests at notified testing bodies, the closures undergo not only smoke tests but also durability tests with 200,000 closing and opening cycles.
A fire protection closure therefore does not automatically also comply with DIN 18095. If closures with combined fire and smoke protection are required, doors and flaps must be used that satisfy both requirements.
Avoiding the replacement of still intact protective doors
The closures installed in the Trianon tower in 1992 and 1993 still meet all fire protection requirements today, but offered only limited and untested protection against the spread of smoke in the event of a fire.
"Even more than 20 years after installation, the fire protection closures in the skyscraper were still in flawless condition. We therefore wanted to avoid having to completely replace the more than 800 doors and flaps and looked for a solution that involved less effort and significantly lower costs for the client," explains Joachim Skowronek, Senior Design Manager and responsible site manager of the Arge Trianon Brandschutzsanierung consortium. The choice fell on the retrofit smoke control system Schröders developed by the Erkelenz-based company Theo Schröders Entwicklung und Beratung GmbH. The system, tested by the Materials Testing Institute NRW for smoke control and durability, allows existing protective doors and flaps to be retrofitted with all-round smoke control and turns existing fire protection closures into fully compliant smoke control doors according to DIN 18095 without them losing their fire protection properties. "By deciding to retrofit the fire resistance doors rather than replace them, we were able to keep costs low and meet the particular challenges of the construction project. All refurbishment measures took place while the building was in operation – the office floors continued to be used. The work therefore had to be carried out at night. The retrofit smoke control system Schröders enabled us to carry out the fire protection refurbishment without much noise, debris, and dust," Skowronek describes the advantages of the process.
More than 800 closures retrofitted and approved
After all existing doors had been inspected, serviced, and any defects remedied, the flaps of the service shafts first received the new smoke control system, followed by the doors in a second step. In total, 845 fire protection closures were retrofitted – including 182 doors that do not originate from System Schröders, but were supplied by other manufacturers in the 1990s.
On behalf of the client, System Schröders applied for fire and smoke protection assessments from MPA Braunschweig (Materials Testing Institute Braunschweig) and the individual approvals from the Regional Council of Darmstadt as the supreme building supervisory authority of the State of Hesse. All retrofitted closures received a new conformity mark with the engraved file number of the individual approval notice.
Project information:
- Construction project: fire protection refurbishment project in the Trianon tower in Frankfurt
- Task: fire and smoke protection refurbishment with a retrofit smoke control system
- Execution: Arge Trianon Brandschutzsanierung consortium under the leadership of Hochtief Building GmbH
- Client: Madison International Realty & Morgan Stanley
- Execution period: 22 April 2014 to 1 April 2015
- Products used: 845 fire protection closures