Horizon House in Syros demonstrates regenerative architecture
Horizon House by ONUS Architecture Studio represents a forward-looking model of sustainable living, combining architectural innovation with ecological sensitivity. Designed for a sloped site on the Greek island of Syros, the residence demonstrates how contemporary architecture can respond to challenging terrain while restoring natural systems. Recipient of the 2025 Architizer A+ Award for Unbuilt Sustainable Residential Project, the house has been recognized internationally for its site-responsive strategies and off-grid energy independence.
The Horizon House design integrates directly with the Cycladic landscape through its semi-subterranean form, which minimizes its visual presence while enhancing environmental performance. By embedding much of the building into the earth, ONUS Architecture Studio reduces energy demands while stabilizing interior temperatures. Stone sourced directly from the excavation site is reused as cladding and structural walls, ensuring that the materials remain tied to the land itself. Reclaimed wood, raw concrete, and native planting complete the palette, resulting in a project rooted in local identity with reduced embodied carbon.
The 230-square-meter house unfolds along a linear axis, parallel to the horizon line. This orientation maximizes southern exposure for passive solar gain, while interior spaces benefit from panoramic views of the Aegean Sea. The northern façade is more sheltered, limiting exposure to strong winds and supporting indoor comfort. Outdoor living is enhanced through an L-shaped pool that not only cools surrounding spaces but also visually connects the home to the island’s topography.
Bioclimatic design strategies form the foundation of the project. Deep-set openings and operable windows ensure natural cross-ventilation, while skylights distribute daylight into central areas. In summer, the mass of the building helps regulate heat, and in winter, sunlight penetration reduces the need for artificial systems. These passive measures reduce reliance on mechanical equipment, lowering both operational costs and environmental impact.
Energy autonomy of Horizon House is achieved through a combination of renewable technologies. Micro wind turbines capture the island’s strong breezes, while a geothermal system manages heating and cooling efficiently. A 300-square-meter green roof collects rainwater, which is processed and stored using a blue roof system, while greywater is recycled for irrigation and other uses. Together, these systems allow Horizon House to operate fully off-grid, emphasizing independence from external resources.
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The surrounding landscape is treated as an integral component of the design. Native vegetation strengthens biodiversity, stabilizes soil, and attracts pollinators. Trees and shrubs are strategically positioned to provide shading and create microclimates that reduce heat gain around the building. Over time, these ecological interventions restore soil quality and water retention, supporting the resilience of the local ecosystem.
Inside, Horizon House emphasizes continuity and simplicity. Natural materials and minimal finishes define the interior atmosphere, allowing light, views, and textures to shape the spatial experience. Courtyards, terraces, and shaded verandas extend living areas outward, creating fluid transitions between indoor and outdoor space. The result is a residence that is both functional and restorative, designed to harmonize with its surroundings rather than dominate them.
Horizon House illustrates how regenerative architecture can become a partner in environmental restoration while offering refined and resilient living conditions. By prioritizing renewable energy, closed-loop water systems, local materials, and biodiversity, ONUS Architecture Studio sets an example for sustainable design on fragile island ecosystems. The project stands as a model of architecture that supports ecological health while providing a contemporary vision of energy-independent living.
3D Render images: ONUS Architecture Studio
