Determining the material intensities of buildings selected by random sampling: A case study from Vienna

Abstract

Many studies calculate the material stock of buildings by using material intensities and reference values for building dimensions. Often, they lack a clear definition of and transparency in the selection of buildings to be analyzed, as well as adequate description for the determination of the material intensities of buildings. This article presents a randomized selection of buildings and determination of their material intensities using the case study of Vienna. On the basis of a digital geo-information building model, buildings were categorized according to their age, use, and volume. From each category, samples were randomly selected and their material intensities as well as different building dimensions were determined based on building documents such as plans. The building dimensions were used to express the material intensities related to different reference values. The 256 objects analyzed correspond to a sample size of 0.11% relative to the total number and 0.22% relative to the total gross volume of objects in Vienna. Although the total material intensities were comparable to other studies, the material intensities of insulation materials in older buildings were found to be higher in this study because of a higher representativeness of the data used. In addition, the expression of the material intensities related to different reference values such as area or volume of buildings improved comparability with other studies. Nevertheless, further research is required, particularly concerning the selection of representative samples of buildings.