Why a gull-wing roof?
When considering year-round living conditions, one might question the practicality of a roof made from tent-like fabric that opens and closes. However, isn’t it appealing to have a room that can be opened up during the mild seasons of the year?

When designing Chiba City Uchiyori Elementary School (Shinkenchiku 9507), the goal was to create classrooms as fluid as Christo’s Umbrellas, and to turn the entire site—including the school building—into a dynamic field that stimulates human activity. The roof, which opens and closes like an umbrella, creates a pleasant space reminiscent of enjoying a beer by the pool.

In this house, as in the school, the aim is to stimulate personal activity—each individual action contributing to a broader, collective energy. Decades from now, this approach may give rise to a “gull-wing village,” where the accumulation of individual activities grows into communal life. The gull-wing roof was born from that vision.

This is a proposal for a new kind of roof—not just one that regulates light, air, and sightlines, but one that alters spatial volume and brings the sky into the interior. The site is located in Hozumi-cho, one station from Ogaki City, Gifu, and is also my parents’ home. It faces the Sai River to the north, where fish are still caught and served fresh, and is surrounded by a pastoral landscape of fields and traditional houses. The Gull Wings House sits nestled among tile-roofed homes built on stone foundations. The 980m² site includes the main house, a detached structure, an old house slated for demolition, and a warehouse.

This project involves expanding the guest room and study of the main house. The connecting roof, made of tent fabric, allows light and breeze to enter the main living room. To ensure a continuous line of sight from the living room to the southern edge of the property, glass screens are used between the living room, guest room, and study.

Just as people change their clothing with the seasons, architecture can also change lightly and flexibly. The combination of the opening gull-wing roof, large sliding doors facing the eastern garden, and an insect screen (soon to be installed) at the eaves allows the building to adapt to the climate, weather, and human activity.

During the mild and summer months, everything is opened up. When the gull-wings are lifted, the ceiling corners open, and the vertical part of the L-shaped roof becomes a soaring 5.5-meter-high ceiling. As the space expands, natural light gradually pours in, and the breeze flows through—it can feel as if the building itself is breathing.

The central counter table in the party room is movable and can serve multiple functions. At night, a mosquito net is attached to the eaves, transforming the terrace into a semi-outdoor space. The house glows like a lantern in the quiet countryside night, gently announcing the presence of human life.

In winter, the gull-wings are closed to create a greenhouse-like environment. We're also considering inserting rigid urethane panels between the tent beams to improve airtightness. The gull-wing doors operate at the push of a button and can be opened or closed individually in about 20 seconds.

Since no conventional system could raise and lower a 180 kg roof using inexpensive, off-the-shelf materials, we repurposed the electric hydraulic lifts (Mini Motion Package) used in transport trucks' gull-wing doors. By using cost-effective materials throughout and simplifying the construction details, we achieved a low cost of 450,000 yen per tsubo.

The shifting boundaries—like a shoreline—are released, drawing attention outward. In a space where inside and outside are on the same level, activity naturally flows and expands without borders.