Takenaka and DesignFuture set circular materials benchmark in Japan

Takenaka Corporation and DesignFuture Japan have established a common evaluation standard for circular building materials, which could aid in accelerating the construction industry’s transition to a circular economy. The new standard is being integrated into a search system on the Material Bank Japan platform, with verification having started in June 2025.

While metrics for CO2 emissions are becoming clearer, there has been no unified standard for assessing the circularity of building materials, such as their recycled content or potential for reuse after demolition. This lack of a clear benchmark has made it difficult for architects and designers to select materials that contribute to environmental performance goals. Furthermore, Japan has set its 2050 carbon neutrality target and prepares for the revised Act on the Promotion of Resource Circulation for Plastics, which comes into force in April 2026. The new system is designed to meet the growing demand from clients who want to use as many circular building materials as efficiently as possible.

The evaluation criteria are based on the Circular Transition Indicators (CTI) framework developed by the World Business Council for Sustainable Development (WBCSD). The system assesses materials based on two key metrics: the “Circular Inflow Rate,” which measures the use of recycled resources in manufacturing, and the “Circular Outflow Rate,” which evaluates the potential for resource reuse at the end of a product’s life.

The partnership has expanded on the original CTI framework to include the quality of recycling. The standard now distinguishes between horizontal recycling (creating the same product), upcycling, downcycling, and energy recovery, providing a more detailed assessment of a material’s true circularity. DesignFuture Japan will build the system’s database by gathering this information directly from material manufacturers.

The “Circular Building Material Search System” is being developed within Material Bank Japan, an online platform used by designers to source and order material samples from over 200 brands. A full-scale trial for Takenaka’s designers is scheduled to begin in December 2025. The companies aim to roll out the feature to all Material Bank Japan members by 2027.