ENGINEERING INSIGHTS | The Skyscraper That Hangs From the Top
What if you built the top floors first, then lifted them into the sky?
That is how BMW’s headquarters in Munich took shape more than 50 years ago.
Designed by Austrian architect Karl Schwanzer, the tower’s four cylindrical office sections hang from a massive cross shaped steel structure at the top of a central concrete core. Even getting the design approved took some imagination: a full size model of an entire office floor was built at Bavaria Film studios to help convince BMW’s decision makers.
Then came the challenge of building it.
Construction began in 1970. The central concrete core reached almost 100 metres within four months. Meanwhile, the uppermost seven floors and an adjoining technical floor were being prepared at ground level.
Using steel tendons and hydraulic equipment, these floors were raised at around four metres per week. Each lift created room underneath for another floor to be assembled and hoisted into position. Glazing and façade work progressed alongside the lifts.
Imagine watching the upper part of an office tower slowly climb its own concrete core while workers build the missing floors beneath it.
The completed structure carries approximately 16,800 tonnes of suspended weight. The load passes through the support at the top, then down the concrete core into the foundations.
Once upper floors were enclosed, interior work could begin while structural construction continued below. After just 16 months, lifting operations were complete, the façade and glazing were in place, and the interiors were already well underway.
Three decades later, the engineering challenge moved inside. The 2004 to 2006 refurbishment improved ventilation, introduced daylight responsive lighting and upgraded fire protection with pressurised stairwells and a dedicated firefighter lift. The exterior remained largely unchanged.
The construction photographs show the part that still makes you stop: office floors being lifted into the sky. The later work is harder to photograph, but it explains how a building this unusual could keep doing an ordinary job: being somewhere people come to work.
