Designed by ONUS Architecture Studio, Horizon House, situated on the island of Syros in Greece, occupies a steep slope with sweeping views of the Aegean Sea. The 230-square-metre residence is partly embedded in the hillside, with the terrain shaping both its form and environmental performance. Stone quarried during excavation has been repurposed for structural walls and cladding, reinforcing the dwelling’s material bond with its setting. Alongside reclaimed timber, raw concrete, and native planting, these choices establish a low-carbon, locally grounded palette.
The home unfolds along a linear axis, aligned with the horizon. South-facing interiors capture uninterrupted views and passive solar gain, while the more protective northern façade shields from prevailing winds. Outdoor life centres on an L-shaped pool, which offers cooling benefits and visually anchors the building to its rocky context.
Bioclimatic principles underpin the design. Deep-set apertures, operable windows, and skylights ensure natural light and cross-ventilation, minimising reliance on mechanical systems. In summer, the combined effect of thermal mass and air circulation helps regulate indoor temperatures.
The house is fully energy-autonomous. Wind turbines take advantage of the island’s breezes, while a geothermal system provides heating and cooling. A green roof, spanning 300 square metres, harvests rainwater through a blue roof system, while greywater treatment enables reuse, supporting off-grid living.
Landscape design enhances ecological regeneration. Native plants improve biodiversity, stabilise soil, and attract pollinators. Trees and shrubs are strategically placed to provide shade and wind protection, enriching the microclimate while supporting long-term soil health and water retention.
Inside, simplicity and continuity define the atmosphere. Spaces are oriented towards natural light and sea views, with minimal finishes that highlight the inherent texture of materials. Fluid thresholds between indoor and outdoor areas extend living spaces into terraces, verandas, and courtyards.
Project & images: onusarchitecture.com/horizon-house/
Article by: Lily Wong
