What is fire-rated joint rope?
Joint rope is a flexible, compressible cord placed in a joint. Usually a fire-rated joint rope is meant: a round seal of mineral or ceramic, non-combustible fibres used to make joints fire-resistant. Because the rope compresses easily, it takes on the shape of the joint. In Dutch it is called a voegkoord.
Fire-rated joint rope
In a fire separation it is not enough for walls and floors to be fire-resistant; the joints between them must be too. An open joint, or one filled with ordinary foam, lets smoke and fire through. A fire-rated joint rope fills the joint with non-combustible material and is often combined with a fire-rated sealant on the face.
The rope comes in various diameters, roughly from 10 to 50 mm. Choose a diameter larger than the joint width so the rope is firmly compressed; suppliers often state a minimum of about 30 percent compression.
Applications: movement joints in fire separations, junctions between wall and floor or ceiling, joints around frames in fire-resistant walls and seals around pipes and furnaces.
Other meaning
In tiling, a simple strong cord is sometimes also called a joint rope. It does the same job as tile spacers: keeping an even joint width between tiles.
Tips
- Follow the tested system: the fire resistance only applies to the combination of rope, sealant, joint width and depth as tested by the manufacturer. Check the test report or classification.
- Do not confuse with backer rod: an ordinary foam backer rod behind a sealant joint is not fire-rated.
- Fill completely: press the rope in without interruptions along the entire length and leave no gaps at corners and butt joints.
- Document: record with photos and a label which product was used; this is often requested at handover and inspection.
Related terms
- Fire resistance
- Expansion joint
- Sealant
- Joint
- Tile spacer
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