Location: Ritto, Japan

Design Team: RAA (Ryuichi Ashizawa Architects & associates)

Area: 407.26 m²

Year: 2024

Photography: Kaori Ichikawa

Design Features: SYMBIOSIS is located in Ritto, Shiga, within a cluster of five agricultural glasshouses built in the 1970s. RAA converted two of the structures into a cafe and a children's space for an experiential farm. Instead of erasing the standardised greenhouse frames, the project retains them as transparent protective shells within which a second, locally rooted architecture can take shape.

At the heart of the cafe is a thatched structure nested inside the glasshouse. Moso bamboo harvested on and around the site forms a reciprocal frame, while split bamboo supports a roof made with sedges, reeds from the Lake Biwa region and rice straw from nearby fields. Local earth is used for rammed-earth and earthen walls. The industrial envelope protects these vulnerable materials from the weather; in return, bamboo, thatch and soil temper a glasshouse environment that would otherwise be difficult to occupy for long periods.

An edible garden surrounds the inner structure. Banana and coffee plants, other tropical species and herbs from Shiga grow as companion planting, making cultivation, harvesting and food part of the architecture's everyday experience. Outside, broadleaf saplings propagated from seeds collected on the site are intended to mature into a denser woodland edge over time.

The children's room is organised by a three-way lattice of 45 mm Shiga cypress members set to a 450 mm grid without metal connectors. Shelves, work surfaces, seating, aquariums and planters can be adapted as activities change. An aquaponic system turns nutrients produced by lake fish into fertiliser for plants, with part of the cycle supporting strawberry cultivation elsewhere on the farm.

The renovation works through coexistence rather than replacement. Transparent greenhouse and thatched shelter, prefabricated construction and local craft, environmental control and biological cycles retain their differences while supporting one another. Here, symbiosis is not simply a project title, but a process visitors can observe through material, growth and maintenance.

Design Team: RAA was founded by architect Ryuichi Ashizawa in 2001. Born in Yokohama in 1971, Ashizawa studied architecture at Waseda University and worked at Tadao Ando Architect & Associates before co-founding Urban Forest Architects in 2000. Working principally from Shiga and Osaka, the practice spans houses, hotels, commercial, educational and production buildings, often extending its scope to furniture, landscape and environmental systems.

The studio understands architecture as part of a wider relationship between nature, society and technology. Its work frequently brings bamboo, earth, timber, planting and water cycles into the structural and spatial logic of a project. Collaboration with structural engineers, environmental consultants, horticultural specialists and builders allows ecological intentions to become durable construction details.

Ashizawa is also a professor in the Department of Environmental Architecture and Design at the University of Shiga Prefecture. The practice's projects include FACTORY IN THE EARTH, ECOTONE HOTEL IN BIWA LAKE and FLUID X, with recognition from the Architectural Institute of Japan and ArchDaily's Building of the Year programme. SYMBIOSIS continues its sustained investigation into local materials, agricultural landscapes and living systems.