Designer Insights: The Future of Offices
Vol.9 Wooden Furniture in Offices: New Impulses for Sustainability
From an abandoned school into a plywood and interior materials factory
The second example is a four-company collaboration between Tree to Green (Tokyo), Salt Terminal (Shiojiri, Nagano), Takenaka Corporation (Osaka) and TANSEISHA (Tokyo). Together, they have launched a project for the production of plywood and treatment of interior materials as a core part of the Kiso Forest Grand Cycle initiative. This initiative aims to establish a circular economy utilising the forest resources of the Kiso region.
This project has the working title Shingohan. The four companies have jointly established a new company called Tsumikasane to advance the plan and will start production of veneer and plywood at two facilities repurposed from disused schools in the Kiso region. Trial operations are due to begin in spring 2026, with full-scale operation planned for autumn of the same year. By turning small-diameter logs, previously difficult to make use of, into plywood suitable for construction and interior applications, the project aims to generate new value from forest resources and revitalise the local economy.
What is the Kiso Forest Grand Cycle initiative?
Takenaka Corporation coined the term Forest Grand Cycle to describe a sustainable virtuous cycle linking forest resources and regional economies and is partnering with forestry operators and local governments to advance the concept. The Kiso Forest Grand Cycle initiative puts this philosophy into practice in Nagano Prefecture’s resource-rich Kiso region.
In the Kiso region, there is an abundance of trees large enough to be used as structural timber. However, roughly half of the forests consist of small-diameter trees, and even when these are felled, only about half of them can be used. They were largely left untouched due to economic unviability. The aim, therefore, is to establish a system that converts these small-diameter and unused trees into building materials while promoting the healthy regeneration of the forest, revitalisation of the regional economy, and effective use of local timber.
The Forest Grand Cycle cannot function in isolation. Two local companies are at its heart: Tree to Green, which operates woodworking and forest education hubs in Kiso, and Salt Terminal, which promotes community development through timber in Naraijuku, a historic district and tourist destination in Shiojiri City.
Joining them are Takenaka Corporation, a general contractor focused on regional revitalisation and the effective, high-value use of forest resources, and TANSEISHA, which promotes the use of wood in commercial and social interior spaces. Together, these two national companies are creating spaces across Japan that explore new possibilities for timber use. Takenaka primarily utilises structural timber, while TANSEISHA plans to use plywood made from small-diameter trees.
Shingohan: a hub for forestry, woodworking and innovation
The Shingohan project is currently being prepared for full-scale operation, with facility renovations and production line setup underway. Drawing on the expertise and networks of all four companies, the aim is to promote the adoption and practical use of building materials developed under the Forest Grand Cycle concept, both in their own projects and through partner organisations.
The initiative seeks to establish a “forestry hub” at the veneer factory in the former Narakawa Junior High School in Shiojiri City for businesses and individuals involved in forestry and woodworking to connect, exchange ideas, and drive innovation. Work on this has started between Takenaka Corporation, the Shiojiri City government, the Shiojiri City Forestry Corporation and Salt Terminal.
Office furniture manufacturers and wooden furniture makers are adjacent industries that have not interacted much in the past, as are general contracting and interior/display industries. This article has highlighted recent examples of collaboration between major companies from these separate industries where they promote more effective use of timber while contributing to regional economies and sustainability.
Many readers will recall that at ORGATEC TOKYO 2025, the Karimoku, Hida Sangyo, and MUJI stands were built around wood-focused initiatives. Furthermore, office furniture manufacturers such as KOKUYO, Okamura and Uchida Yoko have long been active in using domestic and regional timber.
Wood-based design is now recognised as a key strategic choice. Initiatives such as these two examples are helping to create new value in office spaces and serve as models for sustainable regional development. It will be exciting to see how these efforts evolve and what new innovations they will bring.
Acknowledgements:
Report by: Yasushi Yamazaki／Journalist
With a strong interest in design, Yamazaki joined Tanseisha. In 1997, he participated in the launch of the company’s new business venture "Japan Design Net (JDN)". After serving as the editor-in-chief of associated media such as "JDN" and "Toryumon" and as the director of contest planning and production, he became the director of JDN in 2011. In 2025, he transferred to Tanseisha. He engages in interview writing as well as coordinating talks and judging panels.