Ask people to describe a ‘sustainable’ building, and most will begin to wax lyrical about highly-engineered façades, tri-generation systems and photovoltaic panels that span every inch of a roof.
But at its core, a sustainable building is not about technology. It’s about common sense.
A sustainable building responds to its natural environment. Take the Alhambra in Spain. This palace, built by the Moors in the ninth century, is a passively-designed masterpiece in harmony with its natural environment. Water-filled courtyards and heavy vegetation cool the warm air, while deep vestibules covering doors and windows provide ventilation and shade from the hot sun. The Alhambra’s beauty remains an economic anchor for the city of Granada, and a social symbol that connects all Spaniards to their heritage. Environmental, economic and social benefit in one building guarantees its endurance.
Designing buildings like the Alhambra – buildings that exist in harmony with their natural environment – is easier than ever before. Advances in Building Information Modelling (BIM), for instance, enable designers to access historical climatic data relevant to their site with ease, and test solutions against winter and summer solar angles, heat gains and varying temporal wind directions.
This analysis can help us deliver buildings that react to their specific environmental constraints. Passive design solutions based on actual data improve building performance and reduce our dependency on technology and engineered solutions.
In a contemporary context, there are great lessons to be learned from the design process for the European Investment Bank in Luxembourg. The building's architect, Christoph Ingenhoven (well known in Australia for his work on 1 Bligh Street in Sydney) designed a glass shell which envelopes the entire building and maximises natural light. Winter gardens and atria provide thermal insulation and natural ventilation and minimise energy consumption and emissions. The building was one of the first to achieve the UK’s BREEAM Bespoke ‘high environmental quality’ certification with the rating ‘very good’.
Here, conceptual energy modelling as part of the BIM process optimised passive performance. This passive design is supported by active systems including heat recovery. The modelling identified appropriate zoning at the earliest stage of the project, ensuring thermal comfort concepts would function properly. By undertaking integrated flow simulations, the designers identified solutions that enable heat build up to be extracted through atria while at the same time preventing discomfort from excessive wind speeds. This also doubles as part of the smoke extraction system. Daylighting simulations identified glazing strategies which deliver a high degree of transparency and daylight exploitation, in turn ensuring that all eight levels of the building feature good quality working spaces.
Whether examining contemporary or historical examples, there is one constant: our requirement for thermal comfort in space. BIM now helps to identify the parameters needed in every context. Encouragingly, our young generation of designers consider sustainability as an integral component of any building project. Why? Because sustainability really is just good design.