Heliotropic House
In a dense residential area in Osaka, the site faced three roads that each required a building setback. This condition made it extremely challenging to accommodate the client’s requests—including four bedrooms, a laundry room, and a garage—while maintaining a sense of openness in the public area, as the three street frontages also imposed strict building height limitations.
The advantage was that the road-facing sides corresponded to the path of the sun, leading to the image of a space that traces the movement of the sun, almost as if it were heliotropic. As simply increasing the ceiling height was not feasible, the parapet—otherwise subject to the height limit—was slanted and extended, transforming it into a U-shaped void that wraps around the perimeter of the second-floor public area. It creates a sense of openness, allowing the space to visually expand upward despite the restricted ceiling height.
The void volume ultimately rises to form the handrail for the third-floor terrace. Clerestory windows were installed in this rising section to draw light, reflected off the third-floor exterior walls, down into the LDK. The constantly shifting daylight washes over the plaster-finished walls, allowing its varying color temperatures to softly permeate the interior. In a residential neighborhood where physical openness is limited, the design aims to create a space where the daily transitions of light can be intimately felt, evoking the passage of time.
Adapting to height regulations, the parapet is transformed to create a vaulted space around the perimeter of the LDK. It features clerestory windows along the vertical side to allow diffused natural light into the space.
Concept Diagram: Architecture with static heliotropism, tracing the sun's trajectory.
While the physical dimensions of the space are limited, the layering of materials and their textures creates a depth that transcends numerical measurement, perceived instead experientially. Simultaneously, softening the sharp edges and lines formed by the architecture and furnishings gives the space a gentle quality that naturally accommodates the human body.
From the pale light of dawn, through the luminous midday light, to the warm tones around sunset, the ever-changing nuances of light convey the passage of the day.
玄関前の回廊からリビングを望む。柱、梁、垂木といった構造材が広場る田園風景のパースペクティブを強 調する。
To complement the enveloping natural light, the public space is designed to evoke a plaza where people freely gather. Built-in furniture is integrated as part of interior, reinforcing spatial unity and efficiency.
While the southwest corner had the greatest potential for opening, fire-safety regulations limited the allowable window size and required substantial frames. To address this, we composed a large opening using a series of more sensible scale windows, while introducing vertical fins over the frames. The fins tapered with rounded edges create a depth that offers a sense of privacy while gently reflecting the light into the space.
For an exterior exposed on three sides, the curved corners diffuse shadows, while helping the building blend with its surroundings. By emphasizing the contrast against the linear elements, the design aims to achieve an aesthetic that is gentle yet refined.
