Location: Suita, Osaka, Japan

Design Team: Masato Ashida Architects

Area: 120.30 m²

Year: 2024

Photography: Yosuke Otake

Design Features: Masato Ashida Architects designed Esaka Hitotoki Project as a 120.30 m², single-storey timber community hub in the dense urban fabric of Suita, Osaka. A cafe, craft workshop and lawn plaza create a deliberately low-density place for gathering. Rather than treating rural resources as decoration, the project builds an ongoing exchange of people, food, timber and knowledge between the city and the Satoyama landscapes of northern Osaka.

The building extends horizontally along the northern edge of the site, connecting enclosed rooms, a sheltered perimeter, timber decks and the lawn. Glazing makes cafe activity visible from the garden and street, while the deep roof lowers the apparent scale of the pavilion. An open room, shared kitchen, reception area and creative room sit beneath one continuous timber frame, allowing meals, children's activities, woodworking programmes and markets to expand between inside and outside.

Its defining structure uses bark-on deciduous logs sourced from the Satoyama forests of Nose and Toyono. Architects and structural engineers entered the forest to assess each tree, accepting bends, scars and knots rather than milling them into uniform members. The logs and diagonal braces form a simple balance-beam frame. Their natural differences become part of the roof rhythm and spatial scale, making the path from forest material to urban structure directly legible.

Dense broadleaf logs are difficult to dry, so the team used thermochemical reduction to stabilise the whole trunks and worked with Nagoya University's Wood Engineering Laboratory to test their strength. Locally sourced cedar continues across floors, walls, ceilings and exterior decks, keeping structure, enclosure and furniture within a coherent material family. The architecture documents not only a finished surface but also tree selection, testing, treatment, construction and community workshops that produced benches and laid the lawn.

Designed as a ZEB, the project offsets operational energy through conservation and photovoltaic generation. Its 27.59 cubic metres of timber store a certified 18.3 tonnes of CO2. More importantly, the building remains socially active after completion: cafe, woodworking, gardening, environmental education and markets continue to connect urban residents with Satoyama producers. Esaka Hitotoki is therefore less a fixed timber object than a civic framework that can be occupied, maintained and extended over time.

Design Team: Masato Ashida founded Ashida Architect & Associates in 2012, with offices in Tokyo, Kyoto and Tsunan, Niigata. Born in Kyoto in 1975, he studied architecture at Kyoto University and completed a master's degree there before working at Naito Architect & Associates from 2001 to 2011. He later co-founded ENERGY MEET and Future Research Institute while maintaining an active role in architectural education.

The practice works across architecture, interiors, furniture, landscape, civil engineering, urban planning and regional research. Its idea of fudo understands people and environment as interdependent forces that shape one another. Esaka Hitotoki was led by Masato Ashida and GaKin Cyo, with structural engineering by Yamada Noriaki Structural Design Office, landscape by STGK, furniture design and fabrication by kamina & C, construction by Yamamoto Komuten and carpentry by Yasuda Kosho, supported by the Osaka Prefectural Forestry Cooperative.