Variability of results in acoustic measurements in buildings

Abstract

Variability of results in acoustic measurements in buildings depends on different factors, which may lead to different results from those expected. The main sources of variability can be linked to four factors: the measurement method, the nature of the materials, the setting conditions and the effect of workmanship. The variability related to the measurement method (uncertainty) has already been studied in detail in several standards and papers 1,2,3, and it is not considered in this work. On the other hand, the variability related to the other factors (the nature of the materials, the setting conditions, the effect of workmanship) has not been dealt with in detail in the literature 4. However, the understanding of these factors is important during the design phase, in order to define the best technological solutions that will ensure acoustic comfort in buildings and the respect of legal limits. This work aims to evaluate the contribution of each of these latter factors of variability through a statistical approach, applied to an extended campaign of acoustic measurements in buildings. In the present paper, the results of measurements made by the same operator, on the same type of specimen (partition wall and slab), in several flats in the same housing estate, built by the same property developer, are presented. In these conditions the variability due to the measurement method and the nature of the materials was almost constant, therefore it was possible to evaluate the variability due to the setting conditions and the effect of workmanship.