KAEFER Construction - project report

Working our way up to the top of Bonn


Sometimes, sky high ambitions start from the ground up. For a new high-rise in Bonn, KAEFER Construction worked its way up from insulating the parking garage to installing a ground-breaking concept on the floors above.


The former German capital of Bonn isn’t known for its towering skyline. There are just a few tall buildings along the city’s banks of the river Rhine, including the Post Tower and UN Building. At 28 stories and over 100 metres, the new Kanzlerplatz development is destined to stand out in Bonn as a landmark.

Constructed on the site of the former Bonn-Center, which was famously adorned with an oversized Mercedes-Benz emblem, the new tower will take pride of place in the city’s geographical heart.

KAEFER Construction’s role in the project actually started at the bottom of the building. The first order was for the insulation of the underground parking. After successfully demonstrating the company’s skills, KAEFER Construction was commissioned for the complete interior outfitting of the floors above ground, including the walls, ceilings and floors all the way up to the 28th story. “High-rise buildings are a special challenge, especially when you’re pumping screed at 100 metres!” Head of Interior Outfitting Marc Ulke says. “Then there was the ambitious timing, coupled with challenges brought about by the COVID-19 pandemic.”

“High-rise buildings are a challenge, especially when you’re pumping screed at 100 metres!”

Marc Ulke, Head of Interior Outfitting

Rising to the occasion

One might ask at this point whether the concept of a high-rise office building is still relevant in times of increased working from home and enforced social distancing. The key to that lies in the hollow floor concept. Heating, ventilation, electrical cabling, connectivity and supports are all built into the floor, rather than in a mix of walls and ceilings. This makes the interior of the building infinitely variable, as walls can then be put anywhere to accommodate the widest variety of layouts. From open plan offices to smaller workspaces and individually sized rooms that are distant from others, putting the arteries of a building into the floor adapts perfectly to today’s circumstances.

“You have to imagine it like a miniature Autobahn of technology running through the floors of a building. There are various routes that must be followed, and everything has to be placed in exactly the right spot,” Ulke explains. This was a challenge for the client in terms of planning, as well as for suppliers, as there is a very tiny margin for error and little flexibility when working to such a tightly planned concept. Fortunately, Ulke and the KAEFER Construction team had a solution for that as well: “We proactively made a model of the floor, which allowed everyone involved to see exactly where the supports were or the path the communication cables would take, for example,” Ulke says.

This model helped not just with the tendering and planning phase, but also made it easier for suppliers, contractors and the rest of the team to work to plan, as there are up to 100 to 150 fitters working on site at the peak of the project.

Reviving the heart of a city

The building will be completed at the end of 2021 and will then be a welcome addition to the budding skyline of the city of Bonn. In fact, it’s a labour of love for Marc Ulke, as his father was an architect who was involved with work on the old Bonn-Center. That building actually belonged to the Bremer Landesbank, who often worked with KAEFER and Ulke was offered a job at the company while he himself was working in an architectural firm. Now, with the demolition of the old building and the construction of the new one, Ulke can look back with pride at his involvement in defining and breathing new life into the heart of the city of Bonn.