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Cross-Laminated Timber (CLT) is a building technology that is becoming increasingly popular due to its sustainable and eco-friendly nature, as well as its availability. Nevertheless, CLT presents some challenges, especially in terms of impact noise and airborne sound insulation. For this reason, many studies focus on the vibro-acoustic behavior of CLT building elements, to understand their performance, advantages and limitations. In this paper, a 200 mm CLT floor has been characterized in the laboratory, according to ISO standards, by three noise sources: dodecahedron, standard tapping machine and rubber ball. In order to understand the vibro-acoustic behavior of the CLT floor, measurements through the analysis of sound pressure levels and velocity levels, measured by dedicated sensors, were performed. Analysis was carried out in order to understand what is prescribed by the prediction methods available in the literature and by the simulation software. Then, a specific prediction law for the CLT floor under investigation was derived. Finally, an analysis on sound radiation index is provided to complete the vibro-acoustic study.

The acoustic radiation from baffled finite plates with free visco-lastic damping layers excited by a random point force have been studied in order to evaluate damping treatment performances under the condition of neglecting fluid loading due to the back reaction of the radiated acoustic pressure. The plates are rectangular and clamped at the boundaries. The vibration responses of plates with damping layers are obtained by the finite element method. Modal damping ratios are estimated from undamped normal mode results by means of the modal strain energy method.The expressions for the surface acoustic intensity and the radiated sound power are derived in the transform formulation and evaluated numerically from the discrete Fourier transform of the vibration velocity responses of the plates in the spatial co-ordinates. An experimental study is carried out to measure the surface intensity distributions and to compare them with the analytical results.