The project for the house on the Asiago Plateau (Roana, VI) is an excellent example of the integration of contemporary architecture, respect for the landscape and high standards of energy and environmental sustainability. The building skilfully combines meticulous passive design with advanced building services solutions, minimising its carbon footprint both during construction (embodied carbon) and during operation.
Passive Design and Low-Impact Materials
The building’s integration into the topography was achieved by minimising the impact on the ground through a concrete plinth that ‘suspends’ the sleeping area above the natural slope. The upper volume is characterised by the extensive use of timber: a mixed timber/steel structure, external cladding and window and door frames in larch, and internal finishes in spruce. As a renewable resource, timber acts as a carbon sink, drastically reducing emissions associated with the production of building materials.
The building’s orientation has been optimised to maximise free solar gain during the winter months, thanks to a generous south-facing glazed façade. At the same time, control of summer solar gain is ensured by external sunshades consisting of vertical larch mullions positioned on the east and west sides, which regulate natural light whilst preventing overheating.
Building Envelope Efficiency and NZEB Standards
In terms of thermal performance, the house is certified as a Nearly Zero-Energy Building (NZEB). The building envelope has been designed to ensure the highest level of insulation, which is essential for the mountain climate:
• The external perimeter walls have a thermal transmittance (U) of just 0.147 W/m²K
• The pitched roof with exposed beams boasts a thermal transmittance (U) of 0.136 W/m²K
• The high-efficiency external windows and doors achieve a U_w value of 0.936 W/m²K
• To limit summer heat gain, the glazed surfaces have a solar transmittance (g) reduced to 0.35
Active Systems and Renewable Energy Sources
The low-emissions approach is also reflected in the building services design, which is based on the electrification of energy consumption and the use of renewable energy. The winter heating and domestic hot water (DHW) system utilises a hybrid system that combines an inverter-controlled electric heat pump with a condensing boiler. Heat is distributed via an underfloor radiant heating system, which allows operation at low flow temperatures, maximising the system’s efficiency.
Summary Energy Data
• Photovoltaic System: Integrated into the roof, with a capacity of 1.5 kW.
• Renewable Energy Coverage: The building meets 64.1 per cent of its total energy requirements through renewable sources (well above the legal minimum), rising to 71.7 per cent for domestic hot water production.
• Primary Energy Consumption: The overall non-renewable energy performance index (EP_gl,nr) is extremely low, standing at 30.63 kWh/m² per year.
In summary, the house in Roana is a prime example of sustainable mountain construction, in which the shape of the roof, the use of timber and NZEB building services technology work in synergy to ensure a very low environmental impact and optimal living comfort.
