Circular Interior Design: From Expo to Tokyo

The Core Question

What happens to an interior when its project is over?

It is a simple question, but one that the design industry has not always been good at answering. An exhibition closes, an office is renovated, or a temporary installation is dismantled, and materials that were carefully selected only months earlier can suddenly become unwanted. The Alcazar project offers a different answer: perhaps the end of one interior can become the beginning of another.

This project represents a significant step forward for circular interior design in the commercial sector. It demonstrates a scalable model for the industry: a shift from a linear ‘take-make-dispose’ model to a circular one where materials are viewed as valuable resources in a continuous loop. By extending the life of materials used in a major international event, the project actively reduces the demand for virgin resources and the carbon footprint typically associated with new construction.

From Expo to Office: A Material Journey

The CIC Institute led the transformation of the Alcazar space in Ebisu, Tokyo, in January 2026. The primary innovation was the successful reuse and recontextualization of materials and fixtures from Expo 2025 Osaka, Kansai, giving a second life to components originally designed for a temporary six-month purpose. This approach directly confronts the waste inherent in large-scale events, championing a model of resourcefulness and material intelligence.

To understand why this project matters, it helps to begin in Osaka. Expo 2025 Osaka, Kansai was a major international exposition held from April to October 2025. Beyond its exhibitions and pavilions, the organisers placed considerable emphasis on sustainability, including decarbonisation, resource circulation and the reuse of buildings, equipment, furniture and fixtures. The Japan Pavilion itself was designed with circularity in mind, featuring a circular structure of cross-laminated timber planks intended for disassembly and reuse after the event.

The journey is therefore quite literal: materials that had served one temporary purpose in Osaka were given another purpose hundreds of kilometres away in Tokyo.

The Platform as Bridge

Key to the project’s success was the deployment of the Matinno platform, a circular building-material SaaS developed by NewNormDesign. Matinno provides the crucial infrastructure for a circular economy, enabling the assessment, search, and management of sustainable materials. By using this platform, the project team could effectively identify, evaluate, and integrate the reclaimed materials into the new interior design, ensuring both environmental performance and design integrity.

The platform is not simply a catalogue of second-hand materials. It acts as a bridge between two different moments in the life of an interior. This distinction matters because circular interior design often fails at precisely this point. We may know that reuse is desirable, but desire alone does not create a functioning system. Someone has to know what is available, where it is, when it will become available and whether another project can actually use it.

Matinno handles everything from material matching to end-to-end logistics coordination and environmental impact data calculation. It provided a proprietary map-tracking method to monitor material location and status in real-time. The project was particularly challenging because the demolition of the original Expo installations and the construction of the new office interior had to be coordinated within a demanding schedule.

The Alcazar project demonstrates what happens when that missing connection is deliberately designed into the process.

The Craft of Reuse

The project’s execution was delivered by Semba Corporation, a distinguished Tokyo-based firm listed on the Tokyo Stock Exchange Standard Market, specializing in the planning, design, and construction of commercial facilities. Their expertise in interior design and commercial space creation was instrumental in transforming a disparate collection of reclaimed elements into a cohesive and functional interior for Alcazar.

Semba Corporation’s involvement underscores the necessity of skilled craftsmanship and expert project management in bringing circular interior design principles to life. Their ability to reimagine and repurpose materials for a new context is a testament to their leadership in the field.

Semba has been a pioneer in promoting circular and ethical design practices within the interior construction industry. The company also provided a database of design and construction data from this project, participating as a test case for the implementation of the service. This allowed for the quantitative assessment of environmental load reduction—one of the long-standing challenges in the interior construction industry.

Measuring the Difference

According to CIC Institute, the Tokyo project achieved an estimated reduction of approximately 475 kilograms of CO₂ and also reduced construction waste.

That figure should not be exaggerated. Four hundred and seventy-five kilograms will not transform the global construction industry. Nevertheless, it gives the project something important: a measurable indication that reuse can produce an environmental benefit.

More importantly, the project tests whether the process can work under real project conditions. Because circular interior design cannot remain an attractive idea discussed only in conferences or sustainability reports. It has to work when there are deadlines, budgets, logistics, contractors and clients involved. That is where this example becomes valuable.

A New Role for the Interior Designer

Perhaps the most interesting consequence is the change it suggests for the designer.
For generations, interior design has been closely associated with selection: selecting finishes, furniture, lighting, colours, surfaces and products to create a new environment. Circular interior design adds another responsibility. The designer becomes someone who can discover, assess and give direction to existing resources.

That requires a different kind of creativity. Instead of beginning with an empty material schedule, a project might begin with an inventory. What doors are available? Which lights can be reused? Are there panels, fixtures, furniture or finishes from another project that could be adapted? What can be repaired rather than replaced?

And perhaps the most important question: how can the design make these existing materials feel intentional rather than incidental? When those questions become part of the design process, sustainability stops being a decorative layer added at the end. It becomes part of the design itself.

The Platform Infrastructure for Circularity

Matinno’s vision extends beyond individual projects toward creating a city-wide resource map. The platform’s design includes several notable features:

Environmental assessment indicators: Users can check environmental impact scores when selecting materials, helping designers evaluate environmental information during the design phase

Marketplace functionality: Surplus materials can be listed and procured, translating circular logic into real economic transactions

Digital material passports: By creating building-level material records, future demolition can quickly identify which materials can be reused and which need disposal

This approach addresses a fundamental challenge: without records of what materials are where, in what quantity, and in what condition, selecting reusable materials after demolition means starting from scratch. The cost and time often lead to disposal.

Beyond the Word “Sustainable”

This is also why the Tokyo project is more interesting than simply calling it a “sustainable interior.” The word sustainable has become so common that it can sometimes tell us very little.

What matters is what actually happens. In this case, a group of materials had already served a purpose at a major international event. Rather than assuming their usefulness had ended, another project was found for them. A platform helped identify and match the materials. The materials were transported. They were incorporated into a different interior. And the environmental benefit was calculated.

The process is practical, imperfect and relatively small in scale. Precisely because of that, it feels relevant to everyday interior architecture. Most designers will never design an international exposition. They will, however, work on renovations. They will specify materials. They will replace interiors. They will encounter demolition. And they will have opportunities to decide whether something is discarded or given another chance.

What Tokyo Can Teach Us

The lesson from Tokyo is therefore not that every interior should look recycled. Nor is it that designers should stop using new materials. The lesson is more subtle. Newness should not automatically be the default. Before ordering something new, there may be value in looking at what already exists. Before demolishing a space, there may be value in understanding what can be retained. Before sending materials away, there may be another project waiting for them.

This requires better information, better coordination and, importantly, a willingness among designers, clients, contractors and suppliers to work differently. The Tokyo project shows one possible model. It connects an international event in Osaka with an office renovation in Tokyo, while a material platform provides the information and coordination needed to make the connection possible. That may sound like a small change. But circular systems are built from exactly these kinds of connections.

Conclusion: Giving Materials Another Chapter

The most sustainable material may not always be the newest material, the most technologically advanced material or even the material marketed specifically as “green.” Sometimes, it may be the material that is already here. The project in Tokyo makes that idea tangible. Materials used for a short period at Expo 2025 Osaka were not simply treated as remnants of an event that had finished. Instead, they became resources for another interior.

For interior designers and architects, this suggests a more thoughtful way of working. A material does not necessarily have one project, one location or one moment in its life. It can move. It can be adapted. It can be repaired. It can become part of something unexpected.And perhaps that is where circular interior design becomes most meaningful—not when sustainability is added to the design brief, but when designers begin to see the built environment as a collection of resources with lives that can continue.

The Tokyo project does not offer a complete answer to the problem of construction waste. It offers something more useful: a practical question for the next project. Before we buy something new, what if we first ask what we can give another life?