RE4 stands for “Reuse and Recycling of CDW materials and structures in energy efficient pREfabricated elements for building REfurbishment and construction”. It is a 42-month collaborative research project, funded by the European Union’s Horizon 2020 research and innovation program (Grant Agreement No 723583), started in September 2016.

RE4, coordinated by CETMA, involves other 13 Partners from 8 Countries (Italy, Spain, Sweden, Germany, Belgium, UK, Czech Republic, and Taiwan) who cooperate to achieve the goals of the project.

The academic and industrial Partners’ skills cover all process phases:  the advanced technologies for CDW sorting, the recycling of secondary raw materials and reuse of components from demolition activities, the development, and manufacturing of new building materials and eco-sustainable components and finally the validation of materials and technologies developed.

The main objective of RE4 is to develop an RE4 prefabricated energy-efficient building concept that can be easily assembled and disassembled for future reuse, containing up to 65% in weight of recycled materials from CDW. The reusable structures will range from 15-20% for existing buildings to 80-90% for the RE4 prefabricated building concept.

Several intermediate but self-standing industrial results have been proposed:

  • Innovative and effective solutions in terms of sorting technology in the CDW recycling value chain.
  • Pre-fab building components made of recycled materials and related production processes and equipment.
  • Development of a BIM-compatible tool with the aim of supporting owners and construction/demolition companies by providing an estimation of the types and quantities of CDW that will be generated during construction/demolition phase, with possible utilization options and related logistic references.


The approach and technology developed at the lab scale will be scaled-up through the set-up of pilot-scale manufacturing lines for the innovative sorting of CDW and the production of structural, non-structural and lightweight prefabricated element integrating CDW, in order to validate the feasibility of industrial production in safe conditions.

Using the pilot plants, representative prototypes of the final components will be designed, produced, tested and applied on real-scale structures for validation and demonstration purposes. RE4 prefabricated components will be finally demonstrated and validated through the assembling of the RE4 prefabricated energy-e­fficient building concept that can be easily installed and disassembled for future reuse. Anti-seismic performances will be also demonstrated through shaking table testing.