Structure-borne sound in buildings: Advances in measurement and prediction methods

Abstract

This article coincides with recent publications of international standards, which provide methods of predicting the performance of both heavyweight and lightweight buildings in terms of airborne sound insulation and impact sound isolation, from the performance of individual elements such as walls and floors. The performances of the elements are characterized by the sound reduction index and the impact sound pressure level. To predict the sound pressure level due to vibrating sources (i.e., mechanical installations, water services and other appliances), source data are required in a form appropriate as input for prediction models similar to the above, i.e., as equivalent single quantities and frequency band-averaged values. Three quantities are required for estimating the structure-borne power for a wide range of installation conditions: activity (the free velocity or the blocked force of the operating source), source mobility (or the inverse, impedance) and receiver mobility (or impedance) of the connected building element. Methods are described for obtaining these source quantities, including by using laboratory reception plates. The article concludes with a proposed database, based on laboratory measurements and simple mobility calculations, which provides a practical approach to predicting structureborne sound in buildings.