Circular economy: over 90% of all mineral construction waste recycled for the first time
The Initiative Kreislauf Wirtschaft Bau publishes the 14th monitoring report on the generation and fate of mineral construction and demolition waste.
The efficient use of resources has increasingly moved to the centre of political debates in recent years. As part of its taxonomy, the European Union defines the transition to a circular economy as one of six key sustainability goals. The construction sector has a major responsibility in this regard, as more than half of the waste generated in Germany consists of mineral construction waste, of which almost 60% (58.7%) is soil and stone.
On 6 December 2024, the Initiative Kreislaufwirtschaft Bau published its 14th monitoring report on the generation and fate of mineral construction and demolition waste. The report is based on official data from the Federal Statistical Office and describes the situation in 2022. Back in the 1990s, the key associations of the construction materials industry, the construction sector and the waste management industry joined forces to form the Circular Economy in Construction initiative in order to recycle mineral construction waste in an environmentally friendly manner and minimise its landfilling.
Of the total of around 208 million tonnes of mineral construction waste, 188 million tonnes were recycled in an environmentally friendly manner in 2022. For the first time, over 90% of construction waste was recycled. While only just under 87% of excavated soil was recycled, the recycling rate for granular mineral construction waste, such as building rubble and road demolition waste, was just under 96%. The granular mineral waste processed into RC construction materials replaced 13.3 % of the demand for primary aggregates; taking industrial by-products into account, the substitution rate is 17.9 %. ‘The construction sector shows how the circular economy can work. The companies avoid landfill, process the waste into RC building materials and then reuse them in construction projects. This conserves natural resources,’ says Dr Berthold Schäfer, spokesperson for the Initiative Kreislaufwirtschaft Bau.
The associations involved were satisfied with the result. However, as the potential of mineral construction waste in terms of material substitution is almost exhausted today, the associations involved reacted with incomprehension to the political objectives adopted by the Federal Cabinet as part of the national circular economy strategy to double the substitution rate in the future. ‘The substitution rate depends on the total demand for aggregates and the volume of waste. We cannot utilise more than 100 % of the waste. As the demand for housing, infrastructure or the energy transition is significantly greater than the volume of waste, the substitution rate cannot be increased at will. As more refurbishment and less new construction is also planned for the future, the substitution rate is likely to fall in the future despite all efforts,’ Schäfer explains. ‘The substitution rate is therefore not the right yardstick for assessing the success of the circular economy in the construction sector.’
Mantelverordnung not a driver for more circular economy
This 14th monitoring report with data for 2022 is the initiative’s last report based on the legal framework of the LAGA.
The next report, with data for 2024, will be based for the first time on the legal framework of the standardised German Mantelverordnung. The Mantelverordnung has been in force since August 2023 and is characterised by non-harmonised limit values for adjacent legal areas, more bureaucracy and higher costs. This could increase landfilling and reduce the recycling rate. The Construction Circular Economy Initiative is therefore calling for more sense of proportion from
politicians. ‘Ambitious targets in the area of circular economy are the right thing to do, but they must be realistically aligned with volumes, legal hurdles and foreseeable demand,’ says Schäfer.
The “Mineral Construction Waste” monitoring reports are available free of charge online (only in German) at www.kreislaufwirtschaft-bau.de.