Onus Architecture Studio has completed Horizon House, an innovative net-zero residence that demonstrates the future of sustainable living on the Greek island of Syros. The 230-square-meter home represents a breakthrough in regenerative design, going beyond traditional sustainability practices to actively restore and support natural ecosystems. Built into the sloped terrain of the Aegean landscape, the house is partially embedded in the earth and constructed using stone excavated directly from the building site.
The Athens-based architecture firm designed the residence to function completely off-grid while supporting the surrounding environment. This approach reflects a growing movement in architecture toward regenerative design, which actively helps restore natural systems rather than simply minimizing environmental impact. The project combines passive solar design principles, efficient resource utilization, and low-impact construction techniques specifically tailored to the unique challenges of island living, including drought conditions, strong winds, and rising temperatures.
Horizon House follows the natural contours of the steep hillside, with a linear layout that stretches along the horizon overlooking the Aegean Sea. The architectural team strategically positioned south-facing openings to maximize natural sunlight penetration throughout the day, while the more enclosed northern facade protects residents from the region's prevailing winds. The structure incorporates raw concrete, reclaimed wood, and native vegetation to seamlessly integrate with its Mediterranean context.
The home's energy performance is optimized through carefully implemented passive design strategies. Deep-set apertures and operable skylights work together to maximize natural light and promote airflow throughout the interior spaces. The architects combined the thermal mass of the concrete structure with precisely oriented shading elements and a vegetated roof system to maintain comfortable interior temperatures year-round without relying on mechanical heating or cooling systems. This passive performance is enhanced by micro wind turbines that harness the island's constant winds and a geothermal loop system that provides additional heating and cooling capacity.
Water management represents another key innovation of the project, with all water needs handled entirely on-site through integrated green and blue roof systems. The green roof functions as a rainwater catchment system that feeds into a blue roof infrastructure designed to store and filter collected rainwater for household use. Greywater from sinks, showers, and washing machines is treated on-site and reused for irrigation purposes. The landscaping design exclusively features native plant species, which reduces water demand while promoting local biodiversity and improving soil health over time.
The architects carefully planned the outdoor spaces to improve the local microclimate and reduce wind exposure. Strategic placement of trees and shrubs creates natural windbreaks and provides additional cooling through evapotranspiration. These landscape elements work together to create a more comfortable outdoor environment while supporting the region's natural ecosystem.
Inside the residence, the same principles of environmental harmony and material restraint continue throughout the interior design. Natural materials complete the interior spaces, where living areas and bedrooms are arranged along the main view axis to maximize ocean vistas. The floor plan takes full advantage of the dramatic site, with each room oriented to capture specific views and natural light conditions throughout the day.
The indoor-outdoor living experience is enhanced through a series of courtyards, verandas, and shaded terraces that extend the functional space of the house beyond its physical walls. These outdoor rooms provide comfortable gathering spaces while taking advantage of the Mediterranean climate and spectacular views of the Aegean Sea. The design demonstrates how contemporary architecture can work in harmony with natural systems while providing all the comfort and functionality expected in modern residential design.
