Field study on the sound insulation performance of a CLT residential building in a subtropical climate

Cross-laminated Timber (CLT), promoted in Asian countries recently, has many advantages, including thermal insulation, fireproof, and anti-seismic characteristics. However, the wood’s density is much lighter than Reinforced Concrete (RC), which may result in CLT’s inferior sound insulation performance. Compared to considerable research in western countries that discussed the sound insulation performance of CLT, related research in the acoustic field of CLT in a subtropical climate is lacking. Therefore, this study’s objective is to understand CLT’s sound insulation performance in a subtropical climate by using field measurements and comparing them with different structural materials like RC in the same climate. In this research, the sound insulation of the external wall and partition walls, as well as the impact sound of the floor in a five-story, CLT residential building in Taichung was measured in the field using ISO 140-5, ISO 140-4, and ISO 140-7 standards. Furthermore, we compared the measured results with those of a previous study that had field measured a RC building in order to understand the relative sound insulation performance of CLT in a subtropical climate. The results showed that, compared to the external wall, the insulation performance of CLT at all frequency bands is lower than that of RC, The smaller difference varies between 500-1000 Hz. When compared to the partition wall, the insulation performance of CLT is also inferior to that of RC, the difference in the low to medium frequency band is obvious relative. Comparing the floor, the sound insulation value of CLT is lower than that of RC under 800 Hz, but the value of CLT is clearly higher than that of RC at values over 800 Hz. Therefore, in the low frequency band, the sound insulation of CLT performs poorly, while the results are completely opposite at high frequency band.