In a society that is increasingly concerned about sustainability and the effects of greenhouse gas emissions, the conservation of heritage buildings can play a significant role in achieving sustainable urban environments through reductions in the emissions by energy saving and reduction in refuse.
According to the Australian Federal Government, Australia currently emits more than 535 million tonnes of greenhouse gases each year, mainly through the burning of fossil fuels to produce energy. Buildings not only require energy for their ongoing operation, but also have an ‘embodied energy’, which is the energy that has been used to make the building materials and build the structure.
Old buildings represent a huge investment in natural and human resources. The maintenance and conservation of heritage buildings therefore drastically reduces (or eliminates) demolition and new construction waste and conserves the embodied energy already in existing buildings. This fact is supported by many studies that have been undertaken around the world in recent years.
A Department of Environment and Conservation report suggests that Western Australia generates 5 million tonnes of solid waste each year, only 20% of which is recycled or composted. Over 50% of the refuse going to landfill sites is construction and demolition waste – this means we are literally throwing away huge amounts of embodied energy every year.
Commonwealth Scientific and Industrial Research Organisation research estimated that the energy embodied in Australia’s existing buildings is equivalent to the total energy consumption of the nation for ten years. It has established that reuse and recycling of building materials saves about 95% of embodied energy that would otherwise have been wasted. Similar research in Britain considered the energy encapsulated in the materials and construction of a ‘typical’ 1800s house and concluded that the energy it contained was equivalent to 15,000 litres of petrol – enough to drive a car around the world five times or send it half way to the moon.
Clearly reusing as many of our old buildings as possible makes sound environmental sense. The British heritage conservation organisation, Save Britain’s Heritage, suggests:
“Buildings -and not just historic ones- represent energy, labour and materials, which either cannot be replaced or can only be replaced at enormous cost. The fight to save particular buildings or groups of buildings is not the fancy of some impractical antiquarian, it is part of a battle for the sane use of all our resources.”
Heritage buildings not only contribute to our quality of life by adding character and a sense of place to our landscapes, they also play an significant role in creating a sustainable future for our planet.