- 2025 Gold Prize
- From Green Architecture
TOILETOWA
Project Description
All existence is born from the earth and is a circle that returns to the earth.
TOILETOWA is an architecture of circulation and regeneration that makes this visible. More than just a toilet, it was built as an environmental education space attached to the headquarters of Ishizaka Corp in Oak Forest, which recycles industrial waste and serves as a model for a future waste-free, recycling-oriented society.
It is a wooden building consisting of a toilet building with a circular rammed earth wall made of recycled soil NS-10 developed by Ishizaka Corp,, and a tank building that shows the process of perfect recycling and circulating wastewater by combined fermentation of microorganisms. To reduce the environmental impact, the foundation is made of crushed stone instead of concrete. - Made using wooden stakes. With the theme of recycling in the materials used, the interior walls and earthern floors of the toilet building are made of almost recycled materials of soil, wood, and glass. The hand wash and toilet bowls are also made of recycled wood chips.
Toilet wastewater is not only completely recycled and reused but also used as agricultural water to promote the growth of surrounding garden crops. Furthermore, by using natural materials around the building to ``regenerate the earth'' and allowing water and air to pass through the soil from the ground, the forest in the area has been regenerated, creating a refreshing air and atmosphere. The wooden construction was hand-carved by young carpenters, making use of plastering techniques such as rammed earth, plastered walls, hard-packed earthern floor, and mortar polishing counter, and not only the materials but also the circulation of traditional architectural techniques of wood and clay.
■Bio-Toilet Building
Architecture that expresses the ecological circulation of water and air as well as materials and technology.
Most of the building is made from recycled materials and materials that "return to the earth" without using concrete.
Two semicircular rammed earth walls made of recycled earth placed in a staggered manner create a gentle movement and circulation within the forest, and the entire building acts as a well of light, connecting heaven and earth with light coming from the skylights. hook up.
NS-10, the main material used, is recycled soil jointly developed by the owner of the building, Ishizaka Corp. and IS Engineering. A mixture of gypsum board and soil brought to the company from demolished homes by house builders, separated and purified at the company's factory. Until now, it had only been used as a roadbed material for pavement, but this is the first time it has been used as a building material.
Due to the lack of compressive strength, the rammed earth structure was not used as a stand-alone structure, but instead was used as a finishing touch for the wooden framework, and slaked lime was mixed and rammed together to create this rammed earth wall, with a total width of 294 mm, 75 mm each for the middle and outside. Not only that, but it is also used as plaster mixed with lime for partitions, and as hard-packed earthern floor. We tried the possibilities of recycled soil.
■Tank Building
Cobined fermentation has been used in Japan for over 20 years, and here we aim to show the mechanism of water circulation in a sophisticated design as a showcase for the recycling society of the 21st century.
While retaining the existing trees, the complex fermentation process of the fermentation layer, synthesis layer, and catalyst tank is arranged in an arc, expressing the circulation of water with raised beds (three-dimensional vegetable garden) facing a circular courtyard.
In order to keep the overall scale down, the roof has a 2/10 slope on the courtyard side, and the tank can be seen by removing the blind door. The exterior wall is inspired by Local landscape of the forest(Musashino’s Satoyama), and is made of prefecture-produced cedar boards of different widths pasted randomly.
Wood Long Eco, a wood protectant derived from natural materials, is applied to each piece, and each piece changes to a different color as it ages with UV rays. Through the gaps between the boards, people can see sunlight filtering through the trees and see the actual forest, creating a landscape that blends in with the forest.
■Combined fermentation system
A biotechnology called combined fermentation (EMBC) developed by Dr. Yasuhide Takashima is used to treat and regenerate this toilet wastewater. By allowing aerobic bacteria and anaerobic bacteria to coexist, co-prosperate, and coexist, changes in fermentation, decomposition, fermentation synthesis, and fusion occur, and the water is purified and contains zero bacteria, malignant bacteria, and E. coli, making it odorless. Clear enough to drink. The enzyme water created in this process circulates endlessly, and the water containing enzyme-bound crystals activates the soil and has the effect of improving crop productivity.
■ Regeneration of the earth
Along with the construction of this toilet, the surrounding forest and soil were weakening, so WAKUWORKS carried out work to ``regenerate the earth'' of the forest, centering on the toilet, as part of the work to regenerate the forest along with the exterior maintenance.
Plants and plant-derived materials that can be found on the site, such as tree branches, fallen leaves, bamboo charcoal, and charcoal, are buried vertically and horizontally in the soil to create water veins and air flow underground, which aggregates the soil. It activates the functions of the mycelium, root system, microorganisms, and living organisms in the soil, cultivating the inherent power of the soil.
Recycled crushed stone tiles were used to catch rain, and wood chips and lava stone Asama were used for the sidewalks. Through this work, the soil, which was hard and poorly drained, has been cleared of puddles, and as the trees have regenerated, there has been a refreshing breeze, and it is possible to feel that a circulation of water and air has been created in the forest: earth, wood, architecture, and earth.
Trees are also called "pillars of water," and they absorb water from the water veins in the soil and emit water vapor from their leaves. Through this earth regeneration project, an invisible water cycle between the soil and the air was realized, and the forest ecosystem was regenerated along with the water cycle of the toilet's complex fermentation.
■VISION
Earth to Earth.
Tono Mirai is an architect who creates contemporary architecture by using traditional material ‘earth’.His characteristic organic form is made from the flowing spirits in the space that give the human's relief and energy. He gets many prizes in Japan and internationally.
■ PROFILE
Born in Sendai City, Japan, in 1962.
Graduated from the Graduate School of Architecture at Waseda University in 1988. After working for architectural firms, he founded Tono Mirai Architects in 1995.
From 2008 to 2018, he collaborated on research into earth architecture at Maebashi Institute of Technology.
Specializing in environmental architecture using earth and wood, as well as traditional Japanese techniques, he has received numerous architectural awards both in Japan and internationally. He is also active in lectures and publications.
In 1995, he established his own studio and became an architect specializing in contemporary organic earth architecture. Motivated by a family member’s health issues, he designed his own residence and studio, “Kanda SU/Nest House,” to be a place of comfort. Located in central Tokyo, it challenges the typical image of modern apartment housing by featuring an open and fluid design. The renovation utilized traditional Japanese plastering techniques to transform a series of closed and lifeless spaces into a vibrant and nurturing environment. The house reflects the philosophy of shizen (Nature), evolving and regenerating with time.
In 2000, his earth installation “nest=0” opened in London. Visitors from around the world recognized familiar landscapes within its walls, revealing the universal resonance of earth architecture. His signature works—Red Container, Future House, and the iconic Shell House / The Language of the Forest—combine unique and essential design sensibilities with the comfort and character of traditional earthen structures. Advocating for the use of local natural materials and sustainable design, Tono has received multiple international awards and frequently participates in lectures and conferences in Japan and Europe.
His most recent research focuses on the use of the pisé technique in a modern Japanese way that involves the mixed use of wood and earth, and on the potential of reusing earth from construction waste.
He participated in the Architecture Biennale in Venice 2021 with a new site-specific installation, part of the exhibition “Time Space Existence” organised by the European Cultural Center.
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1986 Graduated from Waseda University Department of Architecture in Tokyo. BA.
1988 Completion of the Master's course at Waseda UniversityDepartment of Architecture in Tokyo. MA.
1988-1992 Worked at an architect's studio.
1995 Established Tono Mirai architects, working until now
2008～2018 lecturer at Maebashi Institute of Technology, dept. of architecture.
■ MAIN WORKS
・TOILETOWA
・OYAKI FARM
・Shell House / The language of forest Contemporary mudhouse Japan
・Nest House / Mudhouse in the building
・Future House/ Traditional and modern mudhouse Japan
・House for stories / Spiral Strawbale house
・Nest nursery /lime plastered organic nursery interior
・nest=0 / earth apace installation in London
etc.
● MAIN PRIZES
2025
・TOILETOWA
crQlr Awards 2024 / Circular Awards 2024-Living Loop Prize, Removing the Lid Prize -Organized by: Loftwork Inc., FabCafe Global
Designverse Award 2024–2025 – Spatial Design Category-Special Honor Award Organized by: Designverse
・OYAKI FARM BY IROHADO
The 17th Nagano Architectural Culture Award – General Category
Grand Prize (Governor of Nagano Award) Organized by: Nagano Association of Architects
2024
・TOILETOWA wins Japan Kukan Design Award Bronze and Sustainable Prize
・OYAKI FARM BY IROHADO
APDC DESIGN AWARDS, Asia Pacific Design Center, Excellence Award, Architecture Category
2023・OYAKI FARM BY IROHADO
Finalist Prize, Wooden Construction Category, A+Award 2023, International Architecture Site Architizer, Nagano Prefecture Hometown Forestation Award, Prefectural Governor’s Award, Wood Design Award 2023, 55th Chubu Architectural Award 2023, Japan Wood Growers’ Federation (JWF) Wood Use Competition Excellence Prize, Japan Wood Growers’ Federation Chairman’s Award, Japan Wood Growers’ Federation (JWF) Finalist Prize, Wood Construction Category, International Architecture Site Architizer, Japan Wood Growers’ Federation (JWF) Nagano Prefecture Governor’s Prize, Wood Design Award 2023, 55th Chubu Architectural Award 2023, 36th Nagano City Landscape Award, Tanita Housingware Roofed Architecture Contest 2023, Jury’s Special Prize, Rain Road Design Award, and the Roofed Architecture Design Contest 2023.
・Shell House
The 3rd Japan Federation of Architects & Building Engineers Associations Architectural Work Award, Incentive Award (residential and living space category), 2nd JIA Nagano Architectural Award, Honorable Mention
2022
Director-General’s Prize of the Forestry Agency, 2022 Competition for Superior Facilities Using Wood, organized by the Central Council for the Promotion of Wood Use, and BLT Built Design Awards 2022, Architectural Design Category Prize, international architecture website BLT Built Design Awards.
BUILD BUILD Architecture Awards 2022 Best Sustainable Contemporary Architecture Practice Award
2021
Wood Design Award 2021
Mori Chikara Award, International Architecture Site BUILD BUILD Architecture Awards 2020 (UK), Best Residential Design Award in Japan, Best Architectural Design and Supervision Award, Architectural Institute of Japan, Japan 2020 (100 Outstanding Architectural Works)
2019
Nagano Prefecture Architectural Culture Award, Best Residential Design Award (Prefectural Governor’s Award), Jury’s Award, Residential Design Category, A+Award sponsored by Architizer, an international architecture website
2018
Wood Design Award 2018, Chubu Architectural Award, Residential Section, Special Prize
2016
Contemporary Architecture of the World Soil TERRA AWARD, Honorable Mention
Japan Institute of Architects, Kanto Koshinetsu Branch, Conference Encouragement Award
2013
Japan Plaster Association Work Award .
2011
Japan Plaster Association Award for the Best Work / Children’s Environment Society Award for Encouragement of Design / 1st Prize in the Actual Work Category for a New Traditional Construction House .
2010
Monotsukuri University, 1st Prize in the actual work section of the competition for a house with new traditional construction method .
Children’s Environment Society of Japan Award, Design Encouragement Prize
2008
Excellent Prize, Residence Renovation Competition
2006
Special Prize, Eco-Art Award
2004
Grand Prize, Renovation, Renewal & Conversion Design Competition / Honorable Mention, Interior Planning Award
1999
Nashop Lighting Contest Newcomer Award Dining Bar hana
