Green buildings – Solution for Reducing Climate Change
“Climate change is potentially the greatest challenge to global stability and therefore to national security” stated by the UK national security strategy, Cabinet Office. In other words, the world today is facing tremendous environmental problems caused mainly by climate change. It is the crisis of our time for its impacts are so obvious on the environment and will grow even scarier if no serious efforts are considered; whether we like it or not we are already involved.
Some may claim today that climate change is not that threatening and is caused only by natural sources including changes in the Earth’s orbit, the sun’s intensity, the circulation of the ocean and the atmosphere, and volcanic activity. Although the Earth’s climate has changed many times throughout its history, natural processes alone cannot explain the rapid warming seen today. Abundant data in literature demonstrates that global climate has warmed since the past 150 years. In fact, the 10 warmest years in global meteorological history have all occurred in the past 15 years, and the 20th century has been the warmest globally in the last 600 years. In fact, we can see that alpine glaciers have been retreating, sea levels have risen, and climatic zones are shifting. At the current rate, the Earth’s global average temperature is projected to rise from 3 to 7°F by the year of 2100, and it will get even warmer after that. As the climate continues to warm, more changes are expected to occur, and many effects will become more pronounced over time. For example, heat waves are expected to become more common, severe, and longer lasting. Some storms are likely to become stronger and more frequent, increasing the chances of flooding and damage in coastal communities.
The main reason for this rapid warming nowadays is human actions. In particular, humans cause climate changes to accelerate by releasing greenhouse gases and aerosols into the atmosphere, by changing land surfaces, and by depleting the stratospheric ozone layer. In fact, building construction and operation have extensive direct and indirect impacts on the environment. That is buildings use resources such as energy, water and raw materials, generate waste (occupant, construction and demolition) and emit potentially harmful atmospheric emissions. Statistically, worldwide, buildings are responsible for more than 40% of the total primary energy consumption, 40% of the carbon dioxide emissions, 20% of the water use, and 30% of the raw material use, and 25% wood harvest consumption. Furthermore, the building and construction sector is also responsible for significant non-CO2 GHG emissions such as volatile organic compounds, halocarbons, CFCs, and hydro fluorocarbons (HFCs), due to their applications for cooling, refrigeration, and in the case of halocarbons, insulation materials. Therefore, based on what preceded, the building sector must be one of our main concerns in order to protect our environment from greenhouse emissions and other serious environmental problems that buildings lead to.
What is the approach to reduce climate and global warming?
Green building is the practice of constructing or modifying structures to be environmentally responsible, sustainable and resource-efficient throughout their life cycle. This includes efficiently using energy, water and other natural resources, protecting occupant health, improving employee productivity and reducing waste, pollution and environmental degradation. In fact, creating green buildings has been shown to: reduce energy use by 24%–50%; reduce CO2 emissions by 33%-39%; reduce solid waste by 70% and reduce water usage by 40%.
By this, a green building brings together a vast array of practices, techniques, and skills to reduce and ultimately eliminate the impacts of buildings on the environment and human health. It often emphasizes taking advantage of renewable resources, e.g., using sunlight through passive solar, active solar, and photovoltaic techniques and using plants and trees through green roofs, rain gardens, and reduction of rainwater run-off. Many other techniques are used, such as using wood as a building material, or using packed gravel or permeable concrete instead of conventional concrete or asphalt to enhance replenishment of ground water.
Modern sustainability initiatives call for an integrated and synergistic design to both new construction and in the retrofitting of existing structures. Also known as sustainable design, this approach integrates the building life-cycle with each green practice employed with a design-purpose to create a synergy among the practices used. Today, a great deal of effort is placed all over the world in achieving sustainable development in the construction industry with the aim of reducing energy consumption in both the construction and management of buildings, thus limiting its consequences on the local and global environment. Such effort can be seen at national and international levels with the launching of voluntary building environmental schemes to measure the performance of buildings.
The desire to integrate the various elements of green building has led to the development of rating and certification systems to assess how well a building project meets a specified set of green criteria. In fact, various rating and certification systems have been developed over the years by different organizations and in different regions. While all of these systems address the same general issues and share the goal of measuring and certifying a building’s “greenness,” each system has its own specific processes and requirements. Among these rating systems, LEED, BREEAM & HQE are worldwide approaches that are launched within the last 22 years. The problem therefore lies with how to distinguish the level of sustainability in a building, which will facilitate a direct comparison between each building. This is where sustainability rating tools can potentially play a major role.
To sum up, it is important now to look for sustainable and environmental approaches in building construction and operation if we care about our the future of coming generations to live in clean and healthy environment.