Impact noise reduction: laboratory and field measurements of different materials performances

An investigation of the impact sound insulation performances of different materials currently used as floor coverings in buildings to reduce impact noise is presented in this paper. The following floor coverings for commercial, industrial and residential buildings were tested at the Acoustics Laboratory of the University of Perugia: carpet covering, PVC, corkboard, corkboard with a PVC layer on top, recycled rubber with a PVC layer on top, cork-wood covering, synthetic rubber, undercarpet with carpet on the top. Measurements to evaluate the performances of the floor coverings were carried out, in compliance with UNI EN ISO 140-8: the sound pressure level reduction, due to the installation of a floor covering, was measured in the reverberating room below a heavyweight standard floor. Results were used to calculate, in compliance with UNI EN ISO 717-2, the impact sound attenuation index, ΔLw, useful for a direct comparison between different kinds of floor coverings. Results show that the tested materials haven't good performances: the ΔLw values range from 14 dB (rubber covering) to 35 dB (carpet with undercarpet), so floating floors must be carefully installed to provide a better impact sound attenuation. Finally, field impact sound insulation measurements of a floor equipped with two different coverings were carried out. Results allowed to verify a calculation model for acoustic performances estimation of buildings materials, in compliance with EN UNI 12354-2. A good agreement between measured and calculated data was found.