In-situ sound insulation performance of interior doors with slit-shaped apertures

In a building, doors are one of the weakest building elements regarding sound insulation, which is mainly due to inevitable sound leaks. Although there are some studies based on laboratory experiments, the influence of the aperture on the sound insulation performance under real building conditions have rarely been discussed. This work focused on the total sound insulation of doors with slit-shaped apertures at the bottom. Both in-situ measurements and theoretical predictions were performed on 30 interior doors. The total sound insulation through the door leaf and the aperture was acquired by measurement, and the relationship between the sound insulation performance and the width of aperture was found. The predictions on the total sound insulation were calculated by Gomperts' theory, and were compared with the in-situ measurements. In addition, the effects and the limits of m and n, the numbers indicating the incidence sound field and the aperture position, on prediction were investigated. Accordingly, the proper numbers of m and n were recommended for better prediction of the sound insulation of interior doors.