“Sustainability” is one of the world’s most talked about but least understood words. Its meaning is often clouded by differing interpretations and by a tendency for the subject to be treated superficially. For most companies, countries and individuals who do take the subject seriously the concept of sustainability embraces the preservation of the environment as well as critical development-related issues such as the efficient use of resources, continual social progress, stable economic growth, and the eradication of poverty.

1-The central role of buildings in people's lives

In the world of construction, buildings have the capacity to make a major contribution to a more sustainable future for our planet.

people spend almost 90% of their life inside buildings. In the United States, the annual cost of building-related sickness is estimated to be at $58 billion. Consequently, healthy and comfortable indoor environments contribute significantly to human health and well-being and offer a large potential for reducing ‘external’ costs to societies through lowering diseases. The OECD(The Organisation for Economic Co-operation and Development), for instance, estimates that buildings in developed countries account for more than forty percent of energy consumption over their lifetime (incorporating raw material production, construction, operation, maintenance and decommissioning). Add to this the fact that for the first time in human history over half of the world’s population now lives in urban environments and it’s clear that sustainable buildings have become vital cornerstones for securing long-term environmental, economic and social viability.

2-The challenges of urbanism

Beyond individual buildings, poor patterns of building development often lead to congestion and inefficient use of land, resulting in greater energy consumption and travel time, loss of productivity, polluted runoff to surface water and wastewater treatment systems, loss of agricultural lands, fragmented habitats, and fiscal stress to local communities.

The pace of change means we don’t have the luxury of time. With urban populations worldwide swelling by around one million people every week, there’s an urgent need to come up with clever ideas that optimize the sustainable performance of the buildings that we live and work in.

3- Building a sustainable future by Sustainable Construction

Sustainable construction aims at reducing the environmental impact of a building over its entire lifetime, while optimizing its economic viability and the comfort and safety of its occupants.

Sustainable construction aims to meet present day needs for housing, working environments and infrastructure without compromising the ability of future generations to meet their own needs in times to come. It incorporates elements of economic efficiency, environmental performance and social responsibility – and contributes to the greatest extent when architectural quality, technical innovation and transferability are included.

Sustainable construction involves issues such as the design and management of buildings; materials performance; construction technology and processes; energy and resource efficiency in building, operation and maintenance; robust products and technologies; long-term monitoring; adherence to ethical standards; socially-viable environments; stakeholder participation; occupational health and safety and working conditions; innovative financing models; improvement to existing contextual conditions; interdependencies of landscape, infrastructure, urban fabric and architecture; flexibility in building use, function and change; and the dissemination of knowledge in related academic, technical and social contexts.

While standard building practices are guided by short term economic considerations, sustainable construction is based on best practices which emphasize long term affordability, quality and efficiency. At each stage of the life cycle of the building, it increases comfort and quality of life, while decreasing negative environmental impacts and increasing the economic sustainability of the project. A building designed and constructed in a sustainable way minimizes the use of water, raw materials, energy, land … over the whole life cycle of the building. Sustainable construction also helps achieve gains in human health and prosperity.

4- why is it important to have sustaianble Construction ?

The building sector has a strong global potential to help protect the environment and increase life comfort and well being.

In 1997, scientists and policy makers from around the world met in Kyoto and agreed that by the year 2010, greenhouse gas emissions should be reduced to a level approximately five per cent lower than 1990 levels. Since the Kyoto agreement was signed, many nations around the world have concentrated their efforts on debating the value and responsibilities of sustainable behaviour rather than reducing carbon emissions. Scientists now warn us that 1990 greenhouse gas emissions must be reduced by 20 to 25 per cent by 2020 if we are to avoid the dangerous effects of climate change. Even if the scientists turn out to be incorrect, the over-consumption of non-renewable resources and the accompanying pollution of water, land and the air we breathe cannot be sustained.

Truly sustainable architecture could be defined as the creation of buildings for which only renewable resources are consumed throughout the process of design, construction and operation. Sustainability status must also include the manufacture and transportation of materials, components and construction equipment.

5-The global impact of the building sector on environment

The Earth’s ecosystems are now at a critical stage: they are not only being severely damaged but human activity currently leads to irreversible losses of critical (i.e. life-supporting) ecosystem functions. Buildings and construction works have the largest single share in global resource use and pollution emission.

In 1997, scientists and policy makers from around the world met in Kyoto and agreed that by the year 2010, greenhouse gas emissions should be reduced to a level approximately five per cent lower than 1990 levels. Since the Kyoto agreement was signed, many nations around the world have concentrated their efforts on debating the value and responsibilities of sustainable behaviour rather than reducing carbon emissions.

Scientists now warn us that 1990 greenhouse gas emissions must be reduced by 20 to 25 per cent by 2020 if we are to avoid the dangerous effects of climate change. Even if the scientists turn out to be incorrect, the over-consumption of non-renewable resources and the accompanying pollution of water, land and the air we breathe cannot be sustained.

Truly sustainable architecture could be defined as the creation of buildings for which only renewable resources are consumed throughout the process of design, construction and operation. Sustainability status must also include the manufacture and transportation of materials, components and construction equipment.

Considering that buildings consume over 25 per cent of the raw materials and energy produced in the world, a significant reduction of pollution and greenhouse gas emissions could be achieved in the building industry

1- Sustainable Architecture:

Architects should encourage all levels of government, building owners, and clients to achieve a high level of energy performance for the design and construction of new and renovated buildings. The application of building rating and point systems as well as involving “Accredited Professionals” in the design and commissioning process of a building must not be a replacement for applying careful thought, logical decision-making and skill to the design development and detailing of an energy efficient building. It is important that Clients and Architects clearly understand their respective obligations and responsibilities regarding energy performance targets and objectives. Unrealistic expectations are often followed by disappointment, financial debate and legal wrangling.

2-Sustainable Structure

Sustainable Structure seeks to reduce negative impacts on the environment, and the health and comfort of building occupants, thereby improving building performance. The basic objectives of sustainability are to reduce consumption of non-renewable resources, minimize waste, and create healthy, productive environments.

Sustainable Structure principles include the ability to:

·         optimize site potential;

·         minimize non-renewable energy consumption;

·         use environmentally preferable products;

·         protect and conserve water;

·         enhance indoor environmental quality; and

·         Optimize operational and maintenance practices.

Utilizing a sustainable Structure philosophy encourages decisions at each phase of the design process that will reduce negative impacts on the environment and the health of the occupants, without compromising the bottom line. It is an integrated, holistic approach that encourages compromise and tradeoffs. Such an integrated approach positively impacts all phases of a building's life-cycle, including design, construction, and operation and decommissioning.

3-Sustainable Energy

Buildings account for 40% of energy consumption in most countries, yet their potential for energy efficiency is huge. By using adapted insulation and energy savings techniques, up to 80% of a building’s energy consumption for heating or cooling can be saved.

Buildings could be turned into climate savers rather than remaining energy wasters

Buildings are responsible for at least 40% of energy use in most countries. The absolute figure is rising fast, as construction booms, especially in countries such as China and India. It is essential to act now, because buildings can make a major contribution to tackling climate change and energy use.

Heating and cooling are the main energy consumers in buildings. The use of air condition is estimated to triple before 2030. Most of this energy is wasted due to inadequate insulation.

The huge potential of energy efficiency in buildings has been recognised. Progress can begin immediately because knowledge and technology exist today to slash the energy buildings use, while at the same time improving levels of comfort. By using well-proven energy efficiency measures, 70 to 90 % of a building’s energy need for heating or cooling can be cut.

A strategy for improved energy efficiency of existing buildings is a necessity if the energy consumption is to be reduced significantly over a limited period of time. The life time of buildings ranges from 50 to 100 years and improvement of the existing building stock will thus have much higher impact than the tightening of requirements for new buildings.
“A building has a long life cycle, so its effect on the environment is a long and continuing issue to consider.”

So, Building energy efficiency is the first step toward achieving sustainability in buildings and organizations. Energy efficiency helps control rising energy costs, reduce environmental footprints, and increase the value and competitiveness of buildings. So how do you identify the most effective solutions for achieving sustainability in your building?

The Eurocert ^‘s auditors analyzes your existing energy usage, suggests appropriate energy savings solutions, and puts these ideas into practice. Sustainability is all about using the resources of today efficiently, in a manner that meets our own needs, but doesn’t compromise the ability of others to meet their own needs in the future.