Importance of environmental impact categories in rating systems

Environmental problems which emerges into parallel developed technology, leads global, regional and local several effects. The cause of the majority of these problems is buildings and wrong selection of the construction. In recent years, assessment of buildings environmental impact and certification of building came up under the ?sustainability? concept and developed many method and tools. Therefore, building rating systems are developed tools which measure environmental impact of building and certificate according to sustainibility criteria. Impact categories and importance weights which use construction products impact assessment are different each rating systems. This situation is meant that same construction product rates differently according to each rating systems and was thought reliability of rating systems in assessment of environmental impact of construction products. In this context, the aim of thesis is, determined the quantitative and percentile difference in impact result value of product according to different importance weights and is examined reliability of systems.In this working of thesis, environmental impact values of brick, aerated concrete and lightweight concrete pumice block are assessed with importance weights of BREEAM and LEED and quantitative and percentile difference obtained environmental impact result values are examined. Thus, impact of importance weightings are measured.