Floor Impact Sound Insulation Using Perforated Gypsum Board Ceiling (04.07)

Apartments in Korea are structured with reinforced concretes, and the noise due to the floor impact sound causes serious problems between neighbors. As a way to reduce the floor impact sound in existing houses, this study applied perforated gypsum boards to apartments ceiling and analyzed a level of floor impact sound. The ceiling structure consisted of perforated gypsum board, glass wool and air layer. To analyze the effective perforated shape of the gypsum board, experiments of sound absorbing coefficient were conducted in the reverberation chamber according to the perforation diameter and spacing and whether the glass wool was present or not. Based on the analysis results, a material that exhibited 0.99 of sound absorbing performance at the 160 Hz band was selected. The floor impact sound was compared when a perforated ceiling structure was installed and general ceiling structure which is consisted of air layer and gypsum board. For the lightweight impact sound, the single number quantity(L'n,AW) did not improve. The heavyweight impact sound (Li,Fmax,AW) showed a reduction of bang machine by 1 dB and rubber ball by 2 dB.