Sumu Yakushima Residence

Before moving to Yakushima, I had already begun to feel uncomfortable with the way sustainability was being discussed.Of course, reducing environmental impact is important. However, whether we install solar panels or reduce carbon emissions, we are often still talking about minimizing damage rather than creating positive change. I kept asking myself: even if we succeed in reducing harm, will the planet truly become healthier? What does the end goal actually look like?At the same time, environmental issues were increasingly being translated into numerical indicators and market mechanisms. Carbon trading, certifications, and sustainability metrics all had their place, but I often felt that the original purpose was being overshadowed by the pursuit of measurable targets. I found myself struggling to distinguish genuine ecological improvement from symbolic gestures.The answer came from Yakushima's natural environment.Nature does not argue through theories; it reveals its answers through outcomes. Where water flows well, life flourishes. Where circulation is blocked, vitality declines. The forest taught me that healthy ecosystems are built not on efficiency but on relationships and cycles.While participating in the restoration of degraded land on Yakushima, I began to see nature itself as the ultimate environmental textbook. Through direct observation, I realized that the most important question was not how to reduce environmental damage, but how to restore and strengthen the cycles of life.Sumu Yakushima emerged from this realization. It became my first attempt to explore whether architecture could move beyond minimizing harm and instead contribute to the regeneration of ecosystems. The project was born from a simple but profound question: can a building help life thrive?

What troubled me most about contemporary environmental discourse was its tendency to rely on a single metric.For example, when carbon reduction becomes the primary measure of success, we risk overlooking other consequences such as biodiversity loss, monoculture plantations, or large-scale deforestation associated with certain renewable energy developments. Nature does not operate through a single indicator, and neither should architecture.Forests, water, soil, plants, animals, fungi, and microorganisms exist within an interconnected system of relationships. When one element is isolated from the whole, we often lose sight of what truly creates ecological health.This is why I place great importance on the concept of the watershed.Rain falls on mountains, flows through forests and rivers, and eventually reaches the sea. Human settlements exist within that journey. Architecture is not separate from this system; it is part of it.For me, a building is not an isolated object. It participates in the movement of water, the health of soil, and the vitality of ecosystems. Its responsibility extends beyond its walls.What Sumu Yakushima proposes is not simply a low-impact building, but an architecture that actively participates in the cycles of life.If human beings are part of nature, then our homes should be capable of enriching nature as well. I believe this shift in perspective represents one of the most important challenges facing architecture today.

While observing Yakushima’s forests, I became fascinated by the immense network of fungi and microorganisms that exists beneath the ground. Healthy forests are supported not only by what we see above the surface, but also by invisible relationships within the soil.At the same time, Japan has a long tradition of using charcoal within landscapes and agricultural systems. Inspired by both ecological observation and traditional knowledge, we incorporated carbonized wood beneath the foundations and used charcoal-based materials throughout the project.Charcoal is highly porous. It retains moisture, air, and nutrients while providing habitat for countless microorganisms. Yet the charcoal itself was never the goal.What we were truly trying to create was an environment that could support biological activity and strengthen the living soil system beneath the building.The results were encouraging. Microbial diversity on the site was measured at levels exceeding those found in the surrounding untreated forest.For me, this finding suggests that architecture does not have to be a force of depletion. Human-made structures can potentially contribute to the enrichment of ecological systems rather than their degradation.I see this not as a construction technique, but as the beginning of a new design philosophy—one that reconnects architecture with soil ecology and recognizes that the health of a building site cannot be separated from the health of the living systems beneath it.