Even if the recycling of debris is a virtuous practice, the deconstruction of buildings would be better
In Italy it is described as one of the most virtuous sectors. In the latest ISPRA (Istituto superiore per la protezione e la ricerca ambientale or Higher Institute for Environmental Protection and Research) report, the recycling of debris – more precisely of building materials – records good percentages. However, most of the material recovery occurs through downcycling, which degrades the quality of the materials.
Downcycling transforms high-quality materials into lower-quality products, preventing future use in their original form. According to an in-depth article published in The Conversation, this approach is not sustainable. The reason is simple: The demand for natural resources is increasing. The alternative is always to reuse, repair or adapt existing materials. But to do so, you need to “disassemble” the buildings carefully to keep the materials at the highest possible value.
Demolition often undermines the quality of materials, pushing reusable tiles, glass and bricks to the landfill. The example given by the authors of the article – two researchers from the University of Lancaster, is that a structural beam can be reinstalled in another building. At the same time, clay bricks can be used again rather than crushed. Downcycling consumes energy and resources, increasing the carbon embedded in construction projects. Prioritizing reuse can significantly reduce the industry’s carbon footprint.
By 2050, 80% of existing buildings must be renovated to improve energy efficiency, preserving as many valuable materials as possible. Deconstruction has already been adopted in several countries, such as France, the Netherlands, Canada, and the United States. Legislation and incentives are needed to promote this approach. The main problem, the researchers point out, is that waste is material without identity. Assigning an identity to building materials through a “material passport” allows us to document their characteristics and facilitate their reuse. This system would prevent valuable materials from being lost or wasted, extending their life and preventing disposal.