Case study of sound insulation performance of a first pure timber 3-story elementary school in Japan

In Japan, "the Act on Promotion of Use of Wood in Buildings to Contribute to the Realization of a Decarbonized Society" promotes the use of wood in buildings in general. The school buildings as public buildings are being promoted to be constructed with timber construction since timber school buildings effectively improve the educational environment. This paper presents the measurement results of the sound insulation performance in "the Uozu City Municipal Hoshinomori Elementary School", which is a first all-timber construction 3-story elementary school in Japan. By adopting a dry-type double floor structure for the floor finish structure and an independent ceiling for the ceiling structure, the floor impact sound insulation performances of the classrooms were Lr-60 for both heavy-weight floor impact sound and light-weight floor impact sound when evaluated using JIS A 1419-2. Moreover, the recommended reverberation time values of the Architectural Institute of Japan Environmental Standards were generally satisfied by installing dressed rockwool sound absorbing board on the ceiling.