Location: Sendai, Japan

Design Team: Architectural Atelier DADA

Area: 162.91 m²

Year: 2021

Photography: Photo Studio Monolith

Design Features: Experimental House with a Large Roof stands on an ordinary, flat, south-facing residential plot in Sendai. Designed by Kyohey Watanabe of Architectural Atelier DADA, the house began with a change in the clients' thinking. Their wish to live close to nature had to be balanced with convenience and family life, leading to a different question: rather than search for a site already rich in landscape, could a home generate its own natural conditions? The 162.91 m², two-storey timber house therefore organises daily life around light, air, planting and bodily perception rather than a pre-existing view.

Its defining move is to give roughly forty per cent of the plan to a walled courtyard and gather both interior and semi-exterior rooms beneath one encompassing roof. Openings of different sizes puncture the canopy, allowing trees, sky and rain to appear intermittently within its deep outline. From the street, dark walls and low eaves preserve privacy. Inside, daylight unfolds through skylights, the courtyard and broad south-facing glazing, while views repeatedly cross spatial boundaries and make the house feel more expansive than its measured area.

The ground floor brings together the entrance, study, hobby room and principal living and dining spaces around an outdoor room paved in Akiu stone. Bedrooms, a second living-kitchen area and a timber deck occupy the upper floor, lifting the family's more private life into the depth of the roof. Extensive glazing faces the courtyard on both levels, while a slatted upper floor keeps light and air moving vertically. Public and private life are distinguished through height, transparency and distance from the garden rather than a simple sequence of closed rooms.

Timber forms the floors, walls and ceilings throughout. Three-layer Hokkaido larch panels provide the horizontal diaphragm while serving simultaneously as the finished floor and the ceiling below; single-layer panels of the same species line walls and upper surfaces. Wood-fibre insulation contributes humidity control and acoustic absorption, while Towada stone and Aomori hiba extend the tactile palette into the bathroom. Structure, finish and joinery are treated as one continuous constructional language, legible in the scale and junctions of the woodwork.

The experiment ultimately lies in environmental changes that can be felt. In summer, water cast across the Akiu stone cools incoming air through evaporation; it then rises through the slatted floor and escapes at the high skylight. The same opening carries soft daylight to the lower level. Natural ventilation, thermal comfort, insulation and local craftsmanship operate together rather than as separate demonstrations. The large roof becomes more than a formal emblem: it is an inhabited device for tuning light, air, temperature and family relationships as the seasons and patterns of life continue to change.

Design Team: Architectural Atelier DADA is based in Sendai and also works from Fukushima and Iwate, with a portfolio spanning private houses, collective housing and mixed-use buildings. The practice describes itself as an evolving group of architects: individual judgement and expertise are developed within a collaborative structure that broadens what architecture can offer to different cities and ways of living. Rather than applying a fixed house style, DADA begins with the inhabitants, the site and the realities of construction, aiming for buildings that become active parts of their local setting.

The project was led by architect Kyohey Watanabe. Born in Yamagata Prefecture in 1984, Watanabe completed both his undergraduate architectural studies and a master's degree in engineering at Utsunomiya University before joining Architectural Atelier DADA in 2009. His residential work gives sustained dialogue with the client a central role, allowing latent spatial ideas to emerge through discussion and construction rather than imposing a predetermined image. His honours include an Excellence Award in the 25th Akita Housing Competition and a commendation in the 12th JIA Tohoku Residential Architecture Award.