Anyone renovating a multi-storey car park from the 1960s is bound to encounter surprises. Contipark’s refurbishment of the Ritterstraße car park in Bielefeld, Germany, evolved step by step from a planned modernisation into one of the most technically challenging construction projects of recent years: around eleven million euros, three years of construction – and a car park equipped for the coming decades.
Demolition would have been the easier option. Contipark decided against it: the load-bearing structure was retained, while almost everything else was renewed. The decision was based on a technical, economic and environmental assessment. “For us, sustainability means more than just energy-efficient technology or modern mobility solutions. It begins with the responsibility to maintain and further develop existing infrastructure where it makes technical and economic sense,” says Michael Kesseler, Managing Director of Contipark Parkgaragengesellschaft mbH.
A building full of surprises
One of the biggest challenges was hidden in the reinforced concrete ceilings. The cables for the original lighting had been laid in metal conduits inside the ceilings. Over the decades these had corroded and turned into unintended water pipes, letting moisture penetrate deep into the structure. Individual repairs were no longer an option. When the joists were exposed, the reinforcement also differed in places from the historical plans – a discovery that alone led to additional work costing nearly one million euros.
“Building a new car park is engineering. Understanding a car park that is over 60 years old and giving it a new lease of life is the art of engineering, with respect for what came before us,” says project manager Wiland Kling, Managing Director of KL-ING. GmbH.
The project in figures
- More than 8,100 m² of ceilings replaced
- Around 1,480 m³ of concrete, delivered by 211 concrete mixers
- 215 tonnes of reinforcing steel and over 44,500 reinforcement connections
- More than 325 heavy-duty supports and over 26 tonnes of bracing
The structure was monitored continuously throughout. When damage to a neighbouring building was reported and the site was initially suspected, a glance at the measurement data was enough: the car park had not moved a single millimetre. During the frost in early 2026, the building was heated so that concrete work could continue.
Team effort on site
Overall planning lay with KL-ING. GmbH and HPI HIMMEN; STRABAG AG carried out the construction work. Other contributors included Henksmeier, Elektro-Licht, Scheidt & Bachmann and Service4Charger. “Of course, a new build would have been easier in many respects. But we wanted to preserve this site. Those who sensibly develop existing infrastructure take responsibility for resources, for the city and for future generations,” says Stephan Opitz, member of the Executive Board and Head of Operations at Contipark.
From car park to smart energy hub
A photovoltaic system on the roof is due to go into operation in autumn 2026. Ritterstraße will then become part of Contipark’s Smart Energy Hub concept, which links photovoltaics, battery storage, charging infrastructure and smart load management. Bielefeld serves as a pilot site for integrating car parks more closely into local energy and mobility concepts. “Developing a car park sustainably today means more than just refurbishing concrete. It means gradually transforming existing buildings into smart mobility and energy hubs,” says Thomas Szlaza, Head of Facility Management.
Olaf Lehwald, Head of the Transport Department of the City of Bielefeld, sees modern multi-storey car parks “just as much a part of sustainable urban development as buses and trains, cycling or attractive footpaths.”
Photo: © Contipark
This article first appeared in Parking Trend International, issue 3-2026, the magazine of the European Parking Association. Read the full issue online.