The uncertainty of sound insulation properties of light weight building elements

Measurement uncertainty is an important topic in building acoustics measurements carried out in the field assessing the sound insulation between rooms as well as conducted in test stands characterizing the sound insulation properties of a building element accurately. Beyond measurement method related contributions to the uncertainty budget there is the variation of the sound insulation properties of the building element itself. According to several studies conducted in the past this uncertainty due to the building element properties can be of a significant quantity. The results of a recent study show that certain aspects of workmanship have significant influence on the sound insulation characteristics of light weight building elements, e.g. timber frame partitions. The method to fasten the planking (e.g. gypsum boards, gypsum fiber boards or chipboards) can lead to considerable variations regarding the sound insulation characteristics and thus to influence also the single values, with variations of the sound reduction index Rw of up to 10 dB. The mounting (i.e. the arrangement of the screws) has considerable influence on the sound insulation properties of this kind of partitions. The airborne sound insulation can be significantly influenced by the number of the screws and by the degree of how firmly they are fixed. The influence of construction details, workmanship, and suggestions how to face this problem will be discussed in the paper.status: publishe