Yakushima-based architecture practice is recognized for advancing regenerative design that integrates biodiversity, fungal networks and traditional Japanese building methods into contemporary architecture.

tono, a regenerative architecture practice based in Yakushima, Japan, has been named the Best in Sustainability Firm at the Architizer A+ Awards 2026, recognizing the firm's long-term commitment to ecological restoration through architecture rather than the achievements of a single project.

Regenerative Vegan House
Photo credit: Shu Ito

Founded in Tokyo in 2016 and relocated to Yakushima in 2020, tono has spent the past six years developing an architectural approach that combines biodiversity, soil health, fungal networks and traditional Japanese building knowledge with contemporary environmental design. The award honors the firm's overall philosophy and practice, highlighting a growing recognition of regenerative architecture within the profession.

Circulation Concept Sketch
Photo credit: Tsukasa Ono

Underground Soil Network Design
Photo credit: Tsukasa Ono

While sustainable architecture has largely focused on reducing environmental impacts, regenerative architecture aims to create positive ecological outcomes. Rather than minimizing damage, the approach seeks to restore biodiversity, strengthen natural systems and leave sites healthier after development. tono's work is based on the idea that architecture should shape relationships between people, land and living ecosystems rather than simply produce buildings.

Tree Recovery
Photo credit: Tsukasa Ono

Electrical Connectivity Verification
Photo credit: Tsukasa Ono

Microbial Diversity Verification
Photo credit: Tsukasa Ono

The firm's move to Yakushima, a UNESCO World Heritage island renowned for its ancient forests and exceptional biodiversity, played a significant role in shaping its design philosophy. Inspired by the island's ecosystems, tono developed a methodology that incorporates ecological processes, water systems, soil health and long-term environmental stewardship into architectural design.

Charred cedar piles and mycelium
Photo credit: Tsukasa Ono

This philosophy is reflected in the firm's design process, which prioritizes working with existing ecosystems instead of replacing them. Large-scale land modification is avoided whenever possible, while traditional Japanese foundation techniques—including charred timber piles and stone foundations—are used to reduce disturbance to the soil. Design decisions also take into account underground fungal networks, wildlife corridors, water cycles and local ecological conditions alongside conventional architectural requirements.

Sumu Yakushima
Photo credit: Rui Nishi

Sumu Yakushima
Photo credit: Rui Nishi

tono's flagship residential project, Sumu Yakushima, exemplifies this approach by combining low-impact construction methods with biodiversity-conscious planning and ecological restoration strategies. The project seeks to create buildings that support healthier ecosystems over time, with the understanding that environmental resilience also contributes to human well-being. The practice refers to its design philosophy as KINCHIKU, an architectural concept that recognizes fungi, microorganisms and living ecological networks as active partners in the design process.

Sumu Yakushima
Photo credit: Rui Nishi

Sumu Yakushima
Photo credit: Rui Nishi

The recognition by the Architizer A+ Awards reflects broader changes within the architectural profession. Increasingly, architects are considering not only what buildings should achieve for their occupants, but also how they can contribute to the restoration of natural environments. The award acknowledges tono's role in advancing this evolving perspective. Since 2022, tono has received more than 40 international design awards. Its flagship project, Sumu Yakushima, has earned 25 international honors, including the iF Design Award Gold and the DFA Design for Asia Awards Grand Award. Unlike those project-based recognitions, the Best in Sustainability Firm award celebrates the firm's long-term philosophy, values and body of work.

Regenerative Vegan House
Photo credit: Shu Ito

Regenerative Vegan House
Photo credit: Shu Ito

Banyan Retreat:The nest
Photo credit: Robert Anderson

Banyan Retreat:The nest
Photo credit: Rui Nishi

Drawing on both traditional Japanese construction knowledge and contemporary environmental technologies, tono combines vernacular building methods with tools such as environmental analysis and Life Cycle Assessment (LCA). The practice describes its work through the concept of Japanese Simplicity, emphasizing an understated architectural expression shaped by harmony with place, climate and living systems. Today, tono works on hospitality, resort and residential developments in Japan and internationally. The practice continues to collaborate with developers, hotel operators and landowners seeking projects that not only reduce environmental impact but also generate lasting ecological value through regenerative design.

tono Inc.

tono Inc. is a regenerative architecture practice based in Yakushima, Japan, founded by architect and KINCHIKU pioneer Tsukasa Ono. The studio combines traditional Japanese building wisdom, contemporary environmental technologies, and ecological design principles to create architecture that enhances both ecosystem health and human well-being.

Since 2022, tono has received more than 40 international design awards. Its flagship project, Sumu Yakushima, has received 25 international awards and is recognized internationally as a pioneering example of regenerative architecture. The practice works across hospitality, resort, and residential developments, helping clients create places that become more alive over time.