Knauf FR Intumescent & Acoustic Mastic is a versatile and economic intumescent sealant used to provide fire resistance in compartment walls (including gypsum stud walls) and floors where openings in these construction elements are formed where linear joints (discontinuities) are located. In a fire attack situation, Knauf FR Intumescent & Acoustic Mastic expands to form a robust char barrier which prevents the passage of flames and hot gases through such openings and which restricts temperature rise on the non-fire side of the wall or floor. Knauf FR Intumescent & Acoustic Mastic can be used with a variety of backing materials and is tested for use with a wide range of gap size, in most cases requiring only a thin layer of sealant. It can be used in low movement linear gaps up to 30mm wide, WITHOUT THE REQUIREMENT FOR ANY BACKING MATERIAL. The product has additionally undergone ’reaction-to-fire’ testing and shown to have low smoke and toxic properties upon combustion. Knauf FR Intumescent & Acoustic Mastic will maintain the acoustic design performance of the seperating element (see acoustic performance data). Knauf FR Intumescent & Acoustic Mastic is available in 310ml cartridges as standard. A bead 12mm x 6mm will fill a gap length of 4.3M (approx.)

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