Experimental study on low-frequency sound insulation of wooden house facades

Lightweight wooden houses have generally poor performance in façade sound insulation at low frequencies. To improve the low-frequency performance of existing houses, increasing the weight of the outer wall and the windowpane, and also installing a double window system are two possible measures. However, the whole mechanism of façade sound insulation is very complicated due to the combination of outer walls and window elements, thus the effect of each measure has not yet fully been clarified especially at low frequencies. In this paper, field sound insulation measurements are performed above 25 Hz for an empty room with volume of 20 m3 in a mock lightweight wooden house, where the above measures for outer wall and window are implemented step by step. The measurement is done in accordance with the low-frequency procedure in ISO 16283-3. The measured results demonstrate the effects of doubling the surface density of the outer wall, of different thickness of glazing, and also of changing the thickness of air layer in a double window system.