The conservation of natural resources is the main objective of the green building approach. A natural resource is a raw material, whose properties are used by humans or other species to satisfy a need. Natural resources can be used in their raw state, with possibly some processes that do not alter them (the case of vegetal and animal resources, but also renewable energies from air, wind, water and the sun). They can also be transformed to be used. The latter mostly involves fossil fuels such as coal, oil, natural gas or uranium.
We can distinguish two types of natural resources: Biological resources and energy resources. Natural biological resources are the water we drink, the soils that we cultivate, the air we breathe, the forests that provide oxygen for the atmosphere, along with all plant and animal species. Natural energy resources are by definition those we use to produce energy. They include air, the sun, water, geothermal sources, plants and fossil fuels.
We can observe that natural resources are running out and that their extraction has harmful effects: Soil erosion, deforestation, destruction of natural habitats, biodiversity and disappearance of fish stocks. The exploitation of these resources generates pollution which to all evidence harms most countries and represents an increasingly dangerous threat to the quality of water, soil and air. Our current production, construction and consumption models, along with global climate change are factors that lead to us to wonder if the planet’s stock of natural resources will remain sufficient to satisfy the needs of a world population that is growing in number and increasingly drawn to live in cities.
We often distinguish renewable resources and non-renewable resources. In terms of renewable resources, we consider those that naturally regenerate, or those that are in unlimited quantities. The two distinctions (biological or energy resources, renewable or non-renewable) can be further sub-divided. Effectively, a resource can be biological and renewable (air), biological and non-renewable (red tuna in the Mediterranean, very soon), energy and renewable (sun) or energy and non-renewable (coal). Today all natural resources are under threat, not just the finite reserves of energy. The most essential is water, which is cruelly lacking in certain regions of the world.
In France, the law of 15 July 1975 on waste elimination and recuperation of materials defines waste as “any residue of a production process, transformation or usage, any substance, material, product or more generally, any furniture that is abandoned or destined to be abandoned by its owner.” In our current society of consumption, goods circulate quickly and are renewed incessantly due to the existence of disposable goods. Waste is therefore produced in greater quantities and in increasingly complex forms.
There are several waste management principles where use varies according to the country or regions. The hierarchy of strategies (the three Rs): Reduce, Reuse and Recycle: classifies waste management policies according to the priorities we wish to assign. Certain experts in waste management have recently added a fourth R: “Rethink,” which implies that the current system has weaknesses and that a perfectly efficient system would require a whole new vision of waste management.
We now need to consider waste as a resource to be exploited and not as waste that we need to get rid of. The methods used to produce new resources from waste are varied and plentiful: For example we can extract raw materials from waste then recycle them or incinerate them to produce electricity. These methods are in full development, notably thanks to contributions from new technologies.
The recycling of waste as raw materials is becoming increasingly popular, in particular in urban areas where space to open new waste management centres is becoming scarcer. Private individuals are therefore required to participate and selective waste collection is increasingly used. Public opinion is clearly evolving towards a position that in the long term, we cannot just dispose of our waste when raw materials are only available in limited quantities. The green building approach naturally integrates optimised waste management.
Respect for the environment
The commercial and residential construction sector can represent up to 40% of primary energy consumption. Overall, it is also responsible for 20 to 25% of waste dumped and 5 to 12% of total water consumption. The United States Green Building Council considers that on average, green building currently reduces energy consumption by 30%, carbon emissions by 35%, water consumption by 30% to 50%, costs relating to waste by 50% to 90%.
A considerable number of research reports confirm the benefits for health and productivity, environmental properties such as natural lighting, the increased use of natural air for ventilation and humidity reduction, the choice of products with low emission rates for carpets, adhesives, paints and other coatings, as well as interior finishing products. In the USA, the annual cost of sickness related to buildings is estimated at 58 billion dollars. According to researchers, the “ecologisation” of construction could achieve annual savings of 200 billion dollars in the USA, simply by improving worker productivity through the improvements of ambient air in office buildings.
Buildings also influence our quality of life, the deployment of infrastructures and transport networks. Bad land management practices often lead to inefficient use of land, which generates higher energy consumption and increased travel time. This can also result in a loss of productivity, the discharge of polluted run-off water into surface water storage and waste water treatment networks, the loss of farm land, the fragmentation of habitats and financial pressure for local authorities.
Reports produced by the world’s leading scientists stress the need to take action on a planetary scale to manage climate change. According to the forecasts of the Intergovernmental Panel on Climate Change (IPCC), if we do not immediately take sufficient measures to limit greenhouse gases, global warming could have irreversible and possibly catastrophic consequences. Every year, the energy used by buildings ejects thousands of megatonnes of CO2 emissions into the atmosphere.
Reports indicate that energy-efficient buildings are one of the fastest and most economical ways of considerably reducing greenhouse gas emissions, and often a source of net economic benefits. An increasing number of organisations, institutions and government entities are demanding a radical improvement in energy yield in the construction sector. In short, the green building approach represents one of the most likely short term methods of considerably reducing emissions responsible for climate change.
According to the IPCC report (ref 2b, 2007, institutional efforts in favour of eco-construction), the building sectors offer the best opportunity to achieve considerable reductions in CO2 emissions. In its fourth evaluation report, the Intergovernmental panel of experts confirms we should be able to eliminate approximately 30% the world’s emissions of greenhouse gases in the construction sector by 2030. With such reductions in energy consumption, renewable sources could satisfy additional energy needs, which would make it possible us to produce buildings with zero net energy consumption and which are carbon neutral. This limitation of CO2 emissions would also improve the quality of interior and exterior air, increase social well-being and secure our energy resources.
The environmental quality of a green building is its ability to satisfy three complementary requirements:
• Control the impacts of the building on the exterior environment
• Create a comfortable and healthy environment for its users
• Preserve natural resources by optimising their use.
This rule applies to construction but also more widely to urban programmes and land management (business parks, zoning, infrastructures, etc.).
It is a concern that stems from discussions at the Rio summit in 1992, where 164 nations met to talk about sustainable development. The construction of a building can in effect have a major negative impact on the quality of our environment. The building sector consumes: 50% of natural resources, 40% energy and 16% of water.
GREEN BUILDING – Ecological construction
GREEN BUILDING – Components
GREEN BUILDING – Environment and climate
GREEN BUILDING – Certifications
SUSTAINABLE DEVELOPMENT AND THE ENVIRONMENTAL FOOTPRINT
GREEN BUILDING – Green installations
GREEN BUILDING – Eco-technologies and practices
GREEN BUILDING – Zero energy home and economic aspects