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Dual board GIB Braceline / GIB Noiseline is an effective wall bracing sheet for light timber framed buildings. It is a high performance plasterboard designed specifically for reducing the level of sound transmission between rooms and even between floors in two storey homes due to its high density core. Other benefits of this product are its 30 and 60minute fire ratings when used in fire systems and its increased strength and stiffness gives a more solid wall or ceiling.