When many people hear the phrase ‘green building’ they immediately think high-tech features and high-spec finishes. They picture advanced low-e glass, blinds that automatically adjust to shield the sun’s rays, blackwater recycling systems, geothermal heating and smart meters that track energy usage.
While green building does embrace and encourage new technologies, new designs and new approaches, many new green buildings are emulating the old designs, the old approaches, the old techniques and nature’s ‘technologies’ to get better, greener outcomes.
Take a simple concept like solar orientation. We have archaeological evidence that the ancient Greeks were building their homes in grid patterns to best access the heat and light of the sun in the fifth century BC. “In houses that look toward the south, the sun penetrates the portico in winter, while in summer the path of the sun is right over our heads and above the roof so that there is shade,” the philosopher Socrates observed, talking about the Northern Hemisphere’s early green buildings.
Greek playwright Aeschylus took his admiration of passive solar design a step further, noting that only primitives “lacked knowledge of houses turned to face the winter sun, dwelling beneath the ground like swarming ants in sunless caves.”
The Ancient Romans developed the first solar-heated bath-houses and access to the sun was made a legal right under the Justinian Code of Law adopted in the sixth century AD. The earliest green roofs, such as the Hanging Gardens of Babylon in what is now Iraq, date back to biblical times.
Sustainable design is not just a feature of the classics, however. Many cultures followed simple principles of sustainable design that remain as relevant today as they were thousands of years ago. Nepalese homes, with their passive solar orientation and shading, high-insulation roofing and rock walls with high thermal mass, have changed little for centuries. The Cappadoccians in Turkey built thermally-efficient homes by hollowing out soft volcanic rock, in much the way the people of Coober Pedy do today. In America, the Pueblo Indians built their dwellings with south-facing adobe walls which absorbed the sun’s heat during the day and then warmed the home’s interior at night.
Indigenous Australians used simple, passive design principles to ensure they gained shelter from our nation’s blazing sun while still allowing air flow, while early colonial buildings integrated elements of passive design. The magnetic termite mounds of the Northern Territory are miniature ‘termite cities’ aligned north to south to minimise exposure to the heat of the sun, with structures that keep temperatures stable within the mound, allow air flow, and help shed excess rainwater without being washed away. Recall the old Queenslanders perched on stilts to improve air flow, inner-Sydney terrace houses pushed up against each other to provide good thermal mass, and the shade and shelter gained from the ubiquitous verandah.
As these examples demonstrate, until fairly recently human beings were adept at living in harmony with our climate and our environment. Where did it all go wrong? The post-war boom required as many homes to be built as quickly as possible. Later, a focus on minimising costs resulted in suburb-upon-suburb of sealed brick boxes – each designed in a way that ensured they would trap the heat in summer and block out the sun in winter, requiring mechanical air conditioning to assure thermal comfort. In fact, the invention and commercialisation of air-conditioning led us to lose touch with the concept of building our shelter around the seasons. When the same building design could be applied everywhere from the Top End to Tasmania, little thought was given to the local climate and ecosystem, not to mention the aesthetics of the suburban landscape. Air conditioning remains a valuable part of indoor environment quality, but should be used to complement good passive design, rather than the starting point of architecture.
So, the shift to sustainable building is not really a progression – more a return to simple, common sense methods of good, green passive design.
Take Australia’s first Green Star-rated residential development, The Summer in Perth, as an example. The Summer has integrated simple design features that use the ocean breeze and regulate the heat generated by the sun. The result is a development that has eliminated the need for mechanical air-conditioning, and is estimated to reduce greenhouse gas emissions by 88 per cent.
Through passive design strategies, over 90 per cent of units have open floor plans and provide dual aspects to allow for natural cross-ventilation, recirculating air throughout the units and common spaces. The building also incorporates moveable screens on balconies to provide solar shading in the warmer months.
The design principles applied at The Summer evoke the Queenslanders of yesteryear – demonstrating that everything old can be new again.
Robin Mellon is one of Australia’s experts on sustainability in the built environment and is determined to leave the planet in a better shape than it was when he found it. Robin believes in a Better Sydney – better buildings, better communities and a better quality of life.