Commerzbank HQ
Frankfurt, Germany
Architect
Foster + Partners
Client
Commerzbank
Employment
Roger Preston & Partners
The 43-storey tower demystifies conventional thinking that natural ventilation cannot thrive in high-rise design. It demonstrates that the opposite is possible, supported by over 15 years of live operational performance data.
Two offset office fingers flank a rotating, 12-floor sky garden that shifts 120° every four floors, creating an internal climatic buffer, promoting effective natural ventilation across the floor plates. A mixed-mode system uses inward-tipping double-glazed units behind a ventilated single-glazed skin to temper wind pressures outside, while simple inward-tipping windows face the garden. The same openings double as smoke exhaust, successfully validated by CFD and physical smoke tests.
Monitored data show natural ventilation operating over 70 % of the year during the building’s first 15 years – unrivalled environmental performance to date in high-rise buildings.