Numerical Prediction Tools for Low-Frequency Sound Insulation in Lightweight Buildings

Lightweight wooden-framed constructions have steadily increased their market share in Sweden during the last two decades. Achieving acoustic and vibration comfort in wooden-based buildings is, however, still a challenging task. Wood is high in both strength and stiffness in relation to its weight, but its variability has repercussions on how sound propagates, this triggering sound insulation problems. Even if buildings comply with present-to-day regulations, complaints amid residents often arise due to low frequency noise, as it is outside the scope of the standards (where no analyses are performed below 50 Hz). In this investigation, laboratory acoustic sound insulation measurements carried out on a facade element according to the current standards, are intended to be reproduced and calibrated by means of the finite element method. In doing so, the first steps of a numerical predictive tool mimicking the real specimen, from 0 to 100 Hz, are presented. This will enable further research about phenomena occurring in the far low end of the frequency range, which is believed to be the cause of most nuisances reported by residents. Reliable predictive tools for addressing acoustic issues during the design phase avoid additional costs of building test prototypes and ensure a better acoustic performance. (Less)