A simple-to-use retrofit solution from market leaders ROCKWOOL, this intumescent expansion joint seal acts as an effective firestop for construction joints up to 75mm thick in walls and floors. This versatile option has been fully tested to BS476: Part 20 proving its offer of up to four hours' fire protection.

Available in a host of sizes to suit your project, this maintenance-free option is a compressible design that's formed through taking a ROCKWOOL core and shrink wrapping a graphite-based intumescent polymer to each face.

Simply compress the length required by hand then insert it into the joint without the need for adhesives or intumescent sealant. If a fire should occur, the composition of this innovative product will help it to swell and and create a hard char which will prevent flames or smoke from passing through the joint.

Water resistant and ideal for use with blockwork cavities, structural and expansion joints, and curtain wall interfaces, this expertly developed product offers unbeatable fire protection when installed according to the manufacturer's instructions.