Recycled concrete – the future of construction!

We already reported on our pioneering project with recycled concrete last year: The extensive renovation and modernisation measures at the town hall in Korbach were concluded in the summer of 2021. The façade elements made from recycled concrete, also known as RC concrete, were one of the building’s highlights.

The town hall was inaugurated on an open day that was held around one year after the work was completed. All the town’s residents and everyone involved in the renovation work were invited to the official opening and the Hanseatic City presented the new town hall to all those who came.

Something that for many is not obvious at first glance: This pioneering work was initiated purely as a model project to explore the opportunities that urban mining and resource-saving construction are opening up.

What exactly is urban mining and recycled concrete?
Urban mining is basically about creating cycles to preserve raw materials that have already entered into our environment, cities and everyday products.
The benefits are obvious: Urban mining protects scare resources because its main focus is on reusing secondary raw materials. Urban mining also constitutes a cost-effective alternative, particularly at a time when raw materials are becoming more scarce and expensive.
Mineral construction waste – from the demolition of buildings, for example – is processed and used as an aggregate to manufacture recycled concrete. The aggregate from these materials is employed as a substitute for the gravel or crushed natural stone that are normally employed in the production of concrete. It is possible to use crushed old concrete alongside masonry and brick rubble. This creates a variety of interesting colours.

The HERING precast plant manufactured a total of 260 panels for the Korbach project. The panels were blast-finished. The desire was to use the red roof tiles from the demolished building as the colouring component to produce a slightly reddish tinge in the concrete. The existing material was crushed, screened, washed and processed in a crushing plant once the materials had been sorted after demolition. It was possible in the end to use more than 62% of the demolition material for the new building!

One aspect that makes the use of recycled concrete in architecture attractive is the fact that it’s possible to reflect the demolished old structure in the new build’s components. It allows finishes to be realised that reveal the fact that recycled concrete has been used – thus immediately demonstrating that the technology is helping conserve natural resources and protect the environment.