Examination of the categories in which buildings with LEED v3 and v4 certificates score the lowest points in Turkey

In the early years when the industrial revolution in England was effective, with the effect of rapidly developing technology, factories were established in cities and population in cities started to increase rapidly. Although industrialization and urbanization actions were thought to be very important developments in terms of economic development, it has been observed that they have caused environmental problems which have negatively affected the lives of all people over time. As a result of production and new technological developments in factories, decreasing of natural resources used unconsciously, spreading fossil fuels and toxic wastes to the environment, and reinforced green areas are the most important environmental problems. The adverse effects caused by these environmental problems in the following periods have caused global warming and climate change. Since the 19. century, as global warming has become a threat to all the world's people, instead of the economic development process that was effective at that time, the concept of sustainable development has started to gain importance. With the increase in sensitivity to environmental problems, the concept of sustainability has also influenced the construction sector and has revealed building types which are called "environmentally friendly" or "green buildings". As the interest in green building projects increased, developed countries have issued Green Building assessment certificates to certify the environmental impact of these buildings, to reference other projects, to accelerate implementation processes and to encourage the whole world to green building. In 1990, the BREEAM(Building research Environmental Assessment Method) certificate was issued in the UK where industrial revolution began and environmental problems were seen most. Later, in the United States in 1998, LEED (Leadership in energy and Environmental Design) certificate was published and BREEAM certificate with the most widely used certificates have become. Recognition of green buildings in our country and taking place in the construction sector started in 2007. ÇEDBIK(environmental friendly green buildings association) was established in order to carry out studies and researches on green buildings in our country and to encourage environmentally friendly buildings in the construction sector. In line with these developments, the first step was taken to create a local Green Building evaluation system in Turkey and the ÇEDBIK-housing certificate was introduced in 2013. By the time we arrived at this time, demand for green buildings has increased rapidly and green buildings have had an effective market in the construction industry. The most preferred Green Building certificate system in Turkey is the LEED certificate which is widely used and recognized in the world. The reason for this is that the scoring system of the LEED certificate is more understandable and easier to apply than other certificates. However, due to the fact that the LEED certificate's scoring system was built according to American local conditions, geographical and climatic characteristics, there are difficulties in the implementation process in Turkey. The aim of this study is to determine the most difficult categories for successful projects in our country regarding LEED certificate and discuss the reasons. At the time of the study, only the projects that received the LEED v3 platinum certificate were analyzed as there were not enough projects from LEED v4, which is the latest version of LEED certificate in our country. As we begin to work, digital data has been collected from the American Green Building Council (USGBC)website, where records of all projects that have received LEED certification worldwide. By evaluating these numerical data, the success rates of all projects in each category have been statistically determined in our country. In line with these statistical results, it has been determined that the projects that have Platinum certificate with the highest degree within the scope of LEED v3 certificate in our country have obtained the lowest success rate from materials and resources category. In the continuation of the study, the LEED certificate materials and resources category was examined individually with all the criteria it included and the reasons why it was the most difficult category to score points in Turkey. In the conclusion section, the work was completed by making suggestions to improve this situation. Keywords: environmental issues, sustainability, green building, LEED Certificate, material.