AGC will work with Obayashi Corporation to recycle waste window glass from its demolition sites into float glass, starting with the former MUFG Bank head office in Tokyo.
AGC has agreed to work with Obayashi Corporation to establish a closed-loop recycling process that turns waste window glass from Obayashi’s demolition sites into raw material for AGC’s architectural float glass. The first application will be the demolition of MUFG Bank’s head office in Chiyoda-ku, Tokyo.
Waste window glass collected from the demolition site will be gathered and processed into cullet through an intermediate treatment process. The cullet will then be transported to AGC’s Kashima plant in Kamisu, Ibaraki prefecture, where it will be used as part of the raw material for manufacturing clear float glass, a process that requires high raw-material purity. The resulting architectural flat glass is intended for use in buildings, including projects handled by Obayashi.
According to AGC research conducted in May 2026, this is believed to be the first initiative in Japan to recycle waste window glass from a demolition site as part of the raw material for float glass production. Conventional glass recycling routes have typically turned waste glass into products such as patterned glass and wired glass. Applying the process to clear float glass is expected to widen the range of architectural flat glass products that can use recycled material.
The project builds on a broader push by Obayashi to close material loops on its demolition and construction sites. The contractor launched Japan’s first scheme to reuse structural steel members recovered from demolished buildings in new construction in June 2024, established a closed-loop recycling process for steel scrap in November 2024, and did the same for aluminium scrap in December 2025. Obayashi has also been studying design methods for reuse, developing related technologies and establishing recycling transport processes optimised for its sites.
AGC said it has been working with local governments and private-sector companies to build an integrated system for collecting, processing and supplying waste window glass generated at demolition sites, covering collection, intermediate processing and the supply of cullet as a recycled raw material. AGC’s Yaichi Nojima set out the company’s flat glass recycling plans for Japan in the July/August issue of Glass International.
For the construction sector, the initiative points to a harder technical step than most glass recycling to date. Float glass demands higher raw-material purity than patterned or wired glass, so building a reliable supply chain for post-consumer window cullet is a more demanding proposition than recycling glass into lower-grade products.
