Solarium House by YKAA: A Compact Urban Retreat in Sapporo

In the heart of Sapporo, amidst high-rise buildings, industrial facilities, and urban parking lots, YKAA has designed a compact yet luminous home that balances intimacy and openness. The Solarium House was conceived for a simplicity-loving couple and their three dogs, who envisioned a cozy dwelling with a sunlit central space where family life could flourish. Despite the dense urban setting and limited natural light, the architects transformed the challenge into an opportunity, creating a home that harmonizes natural illumination, spatial continuity, and psychological comfort.

Maximizing Light in a Dense Urban Context

The site posed a significant design challenge: the surrounding cityscape blocked much of the natural light, creating a sense of confinement. To address this, YKAA prioritized the manipulation of light and space. At the core of the design is the Solarium, an atrium that stretches from the northern to southern ends of the house. This central volume acts as the heart of the home, allowing sunlight to penetrate deep into the interior while maintaining privacy from the chaotic outside.

To soften the harsh urban backdrop, the team employed twin-wall polycarbonate panels atop the large atrium windows. These panels diffuse light, creating a soft, natural glow that fills the central space while filtering the urban chaos beyond. Additional skylights and wall openings introduce varying qualities of daylight, enhancing the home’s dynamic lighting throughout the day.

Compact Design with Spatial Fluidity

The 50 m² footprint of Solarium House required a careful balance between compactness and comfort. Private areas such as bedrooms, studios, bathrooms, and storage are strategically positioned along the east and west edges. Their deliberately low ceilings and minimal dimensions cultivate cozy, intimate spaces. In contrast, the Solarium features a double-height ceiling, emphasizing openness and creating a sense of spatial expansiveness rarely found in compact urban homes.

Invisible diagonal lines subtly connect the rooms, creating a seamless flow between private and shared spaces. This fluid spatial organization fosters a sense of continuity, making the home feel less like a collection of rooms and more like a single, unified living environment.

Functionality Meets Comfort

Hokkaido winters are notoriously cold, so insulation and heat retention were critical considerations. Polycarbonate panels over window frames reduce heat loss while maintaining transparency, allowing daylight to filter in without compromising energy efficiency. This sustainable strategy ensures comfort during harsh winters while maintaining visual connectivity to the central Solarium.

The home’s layout encourages both togetherness and privacy. While private rooms offer serene retreats, the Solarium enables family members to remain subtly aware of each other’s presence. From the entrance to the living room, dining area, and staircase, every path converges in the Solarium, reinforcing it as the social and visual nucleus of the house.

A Space to Live, Work, and Dream

Beyond functionality, the Solarium embodies a lifestyle of flexibility and creativity. Its open design accommodates multiple activities: family gatherings, quiet reflection, or working from home. Through careful consideration of light, materiality, and spatial sequencing, YKAA has crafted a home that elevates everyday living. The house is not just a dwelling but an experience—a compact urban oasis where architecture, nature, and daily life harmoniously converge.

All photographs are works of Ikuya Sasaki, Maryana Kovalchuk