NEWS

Forum on sustainable building

These days, the complex relationship between construction and the environment is a fact accepted not only by the industry itself but by a growing number of lay persons as well. Although the knowledge is not always acted upon, in Greece an increasing number of architects and engineers are taking sustainability into account in designing buildings. The first national conference on Buildings and the Environment, held in Athens this week, drew Greek architects and engineers involved in developing systems and materials for a sustainable building environment, that is, reducing the considerable environmental impact of the building industry. In the building boom and demand for cheap housing in Greece that began in the early 1960s and continued into the 1980s, and as Athens’s population swelled due to people emigrating from the countryside, not much thought was given, or in fact could afford to be, to the effect of construction methods and materials on the health of both the inhabitants and their surrounding environment. In the race to put as many buildings up as soon as possible for the largest number of people, little effort was expended in worrying about energy-efficient heating and cooling systems, maximum use of natural light and ventilation, and non-toxic but long-lasting building materials. Even in the rest of Europe, concerns about energy efficiency only really emerged after the petroleum crisis of the early 1970s. As research results began to emerge, people began to realize the huge amounts of energy that buildings absorbed for lighting, hot water, cooking, heating and cooling, and the way these uses contributed to the production of carbon dioxide and therefore the greenhouse effect. The design of buildings and settlements, the production of materials used (a number of building and furnishing materials release toxic substances into the atmosphere), heating and cooling systems, the surrounding area, the construction process itself, and the design of building interiors all came to be recognized as factors involved in the relationship between a building and its environment. At this week’s conference, John Goodall of the Brussels-based European Construction Industry Federation said a turning point in the sector was the signing of Agenda 21, a declaration by the construction industry in 1992 designed to promote economic efficiency and green production methods, and to prevent pollution. He pointed out that 50 percent of all material taken from the earth’s crust is used in construction, 35 percent of greenhouse gas emissions comes from buildings and 40 percent of all waste produced (in terms of weight) is produced by the construction industry. Yet most can be recycled, he said, pointing to incentives for recycling building material that have been introduced in Britain, in the form of landfill charges for disposing of building waste. We are going to see more change, also with regard to life-cycle costing, said Goodall, adding that engineers might soon be required to include far more parameters in their design than are now required. New technologies and research into the toxicity of various building materials have led to the use of alternative products that are of similar if not greater efficiency, but have less adverse effects on the environment, than those used previously. Professor Michalis Papadopoulos, dean of Thessaloniki University’s Civil Engineering Department’s physics laboratory, drew attention to the almost total dependence on polystyrenes as insulating materials in Greece (97 percent), in contrast to the rest of Europe, where inorganic fibers such as fiberglass and rock wool (steel slag with some basalt rock) are increasingly used as well as extruded and expanded polystyrenes and polyurethanes. Other green insulating materials such as cork, wood wool and perlite are not yet in widespread use because of their higher cost. Architect Elli Georgiadou showed examples of two buildings designed using clay and wood. In Greece, clay was always associated with poverty, as a primitive building material, she said, showing examples of modern buildings, one a private home under construction in Panorama, Thessaloniki, the other in Aghios Vlasios, Mt. Pelion, designed using mainly clay and wood. Sustainable building is also about achieving a successful combination of the old and the new. The advantages of aluminum, an increasingly popular building material, were presented by Constantine Manis of the Athens Polytechnic and ELVAL. A non-toxic, flexible material, it can be recycled ad infinitum. Recycling requires only 5 percent of the energy used to produce primary aluminum. About 30 percent of the aluminum produced today is from recycled aluminum scrap, he said. It is one of the most abundant metals in the world, and has a high strength-to-weight ratio and corrosion resistance. Its life cycle, a major factor in determining sustainability, is between 30 to 50 years. The right design and orientation of a building can do much to make use of natural air currents to cool a house in summer and heat it in winter by utilizing the sun’s rays. However, rising living standards and incomes mean that more and more people are taking air conditioning for granted in a city where, just a couple of decades ago, it was considered a luxury in private homes. In Greece, energy consumption in buildings now accounts for 38 percent of the country’s total energy consumption, increasing all the time due to high levels of dependence on air conditioning in summer months, according to architect Evgenia Lazari. The cost of all this waste is a burden on the national economy as well as on the consumer, particularly in countries such as Greece, which imports 72 percent of its fuel. But bioclimatic design, the organization of space within the building based on the rational use and saving of energy, is simply an ‘interesting’ concept for most people, she said, while adding that the interest of a limited number of enlightened architects or home-builders was not enough to bring about change. What is needed is the introduction of institutional and financial incentives to implement alternative methods. Changing the way cities such as Athens are constructed is, of course, impractical, at least regarding what has already been done. Harmonizing constructed space with the natural environment presupposes decentralization, the greatest possible diaspora of small settlements in the natural environment, combined with the strict implementation of clean technologies, said Georgiadou. Papadopoulos mentioned the practical problems involved in Greece, where multiple ownership, such as of apartment houses, remains the rule. Good architects should be aware of the principles of bioclimatic design, he said, but even where the design is based on environmental awareness, it is not always carried out that way by the contractor. There is a lack of control in Greece and designs are often not properly implemented. There is no agency to certify materials and no coordinating body, he said. The first national conference on Buildings and the Environment, organized by Delos Communications, Athens University’s Physics Department and the Athens Center for Ekistics, was held on September 17 and 18.