Tầng lớp trên bề mặt cung cấp các cải tiến đáng kể trong cả hai con đường. Thay đổi gắn kết các hội đồng thạch cao trên sidewalls (hoặc thêm các lớp) không có tác dụng đáng kể cho truyền dẫn đường chéo. Liên kết để tác động tương ứng. | Page 55 of 103 For all the wall floor cases studied the preceding table provides a representative design estimate of the change in Apparent-IIC due to direct transmission plus flanking paths for all significant walls in the room below when toppings are added. If all walls in the room below have their gypsum board mounted on resilient channels those wall surfaces will not contribute significantly to the flanking. This yields the best case with only direct transmission through the floor given in the top row of the table. Note that resilient channels must be mounted between the studs and the gypsum board not between two layers of gypsum board. With the gypsum board attached directly to the wall studs in the room below the Apparent-IIC will be considerably lower. The change due to a topping is almost identical whether the wall has a double layer of gypsum board or a single layer so one row of the table presents the change expected for both cases. For intermediate situations where walls are a mix of these cases a weighted linear average should be used. As an example consider the case with bare OSB topping when the gypsum board of one wall in the lower room is on resilient channels two walls have 2 layers directly attached to the studs and the fourth wall has a single layer directly attached gypsum board the weighted linear average of the values for the Better Floor would be 53 2 2x 48 1 46 1 4 giving Apparent-IIC 50. Summary - Changes to Control Vertical Flanking One apartment above another Impact sound source IRC RR-219 Guide for Sound Insulation in Wood Frame Construction March 2006 Page 56 of 103 Horizontal Flanking in Wood-framed Constructions One apartment beside the other Impact sound source For the case of two apartments horizontally separated by a partition wall assembly there are four key issues J L_ 1. The flanking paths for impact sound are from the floor of the room where the impact occurs to the floor and the surface of the separating wall in the room .
