Topping-out ceremony for the Kolkwitz ReUse Hub: When research becomes a building site

The underlying process was developed by the Structural Recycling field of study at the BTU, led by Prof. Dr.-Ing. Angelika Mettke – who has been conducting research in this field of study for over three decades – as part of the EU research project ‘Horizon 2020 – ReCreate’. The idea is that precast concrete elements from prefabricated block-of-flats should not, as has traditionally been the case, be shredded and reused merely as low-grade road sub-base, but should be given a new lease of life as fully-fledged building components in new buildings. Kolkwitz is not a small-scale test laboratory, but the location where this process is being put into practice for the first time – a first for Germany.

Specifically, a two-storey extension is being built onto the clubhouse – which was erected back in 2009 – using 80 second-hand concrete slabs. These slabs come from a partially demolished and converted block of flats in nearby Großräschen. Individual elements are up to six metres long and weigh just under six tonnes. In the entrance area, a ticket office and a garage for two minibuses are also being built using a further 20 used concrete elements. The construction is being planned and supervised by the Cottbus-based engineering firm Jähne, with completion scheduled for later this year.

Because the load-bearing structure of the slabs already exists and does not need to be newly produced, primary energy consumption during construction is significantly lower than for a conventional new build. According to Mettke’s own calculations, this reduces CO₂ emissions by up to 97 per cent compared with what would be generated if the components were produced from scratch. For the research team – which, alongside Mettke, also includes Viktoria Arnold and Jakob Fischer – the topping-out ceremony is therefore far more than just a milestone in the construction process: it is practical proof that the method they developed at the BTU can be transferred from the laboratory to real-world application. Mettke herself was honoured in October 2025 for her long-standing research with the Swedish Concrete Award, the highest accolade bestowed by the Swedish Concrete Association with distinction.

More than half a million euros in funding

There are also financial reasons why the pilot project is actually becoming a usable building. Back in April, the municipality of Kolkwitz had already received more than 521,000 euros in structural reinforcement funding, presented to Mayor Karsten Schreiber by the Minister-President’s Lusatia Representative, Dr Klaus Freytag. Whilst the structural work is being funded through the EU research project, the state grant covers the interior fit-out and subsequent furnishings.

A building for the whole village

The ReUse Hub is not yet complete following today’s topping-out ceremony – the interior fit-out is still to come. But the direction is clear: in future, the building is to be used far beyond the sports club, for example by the local council or for educational and cultural activities. This means that Kolkwitz is not only gaining a new clubhouse, but also a model project for climate-friendly construction that is attracting attention beyond the region.