Bostik Intucrylic is a water-borne acrylic intumescent building sealant that swells to form a fire resistant insulating char to resist the passage of smoke & flame. Used for sealing expansion, contraction & construction joints ; to seal gaps between fire-rated building components & window/door frames ; & as a service penetration seal for cables & pipes. Assessed to BS 476-20:1987 to give up to 4 hours fire resistance. Joint movement accommodation of ±12.5%. Will not slump in joints up to 30 mm wide. Can be overpainted.