Buildings and homes (or the “built environment”) affects natural environment. Buildings, where people spend 90% of their time, adversely impact human health. Buildings also account for 40% of energy and 16% of the water used annually worldwide. Air quality inside buildings is 2 to 5 times worse than outside
There are many factors to consider while studying the impacts of buildings
• Land use and ecosystems where buildings are built
• Materials and practices used to construct buildings
• Material, chemical, energy and water resources used to maintain and operate buildings
• Demolition and waste of a building at the end of its life
Green Building involves minimizing these negative environmental and human health impacts and enhancing positive results throughout the building’s entire life cycle. In addition to environmental benefits, through integrated design, they can be constructed at the same or lower cost than conventional buildings.
Today, buildings are responsible for more than 40% of global energy used, and as much as one third of global greenhouse gas emissions, both in developed and developing countries. In absolute terms, it is estimated that building-related GHG emissions to be around 8.6 billion metric tons CO2 eqv in 2004. What is particularly worrying is the rate of growth of emissions: between 1971 and 2004, carbon dioxide emissions, including through the use of electricity in buildings is estimated to have grown at a rate of 2.5% per year for commercial buildings and at 1.7% per year for residential buildings. Furthermore, the Buildings and Construction Sector is also responsible for significant non-CO2 GHG emissions such as halocarbons, CFCs, and HCFCs (covered under the Montreal Protocol), and hydro fluorocarbons (HFCs), due to their applications for cooling, refrigeration, and in the case of halocarbons, insulation materials. According to a survey published in 2007, one-third of population believe that global warming is the world’s most critical environmental problem, nearly double the amount of people who agreed with the same statement in 2006 Faiola and Shulman 2007.