Fosroc ExpandaFoam Backing Rod

Fosroc ExpandaFoam (Backing Rod) is a flexible, readily compressible, closed-cell polyethylene joint filler supplied in circular section cords.

Product Advantages

• Readily compressible
• Low load transfer
• Excellent recovery after compression
• Non-absorbent
• Rot-proof
• CFC-free
• Closed-cell polyethylene joint filler, back-up strips and cord
• Standards compliance BS 5628 Part 3 ‘Use of Masonry’ paragraph 20.4.
• DTp Specification for Highway Works, December 1991 series 1000. Clause 1015.

Product Uses

ExpandaFoam is a closed-cell polyethylene joint filler for use as an expansion joint filler in brick and blockwork, isolation joints and hinge joints where a readily compressible low load transfer joint filler is required. Strip and cord sections are also available. These are used as back-up strips for elastomeric sealants. Back-up / bond breaker strip to support sealants Bridge decks, abutments, pier hinge joints Brick and block-work in building superstructures  

Application Instructions

When used as an expansion or isolation joint filler in brickwork, Expandafoam should be positioned to provide for a surface sealing slot of the required dimensions ensuring that the sealing slot is free from mortar droppings or slurry bridging. Expandafoam sheets may be fixed into position using a suitable adhesive. Care should be taken not to contaminate the surfaces of the sealing slot with adhesive. Where Expandafoam is used as the joint filler no additional bond breaker is necessary. Used as a back-up / bond breaker strip Expandafoam serves both to regulate the depth of the sealing slot required and ensures that the movement of the joint sealant is not restricted by three-sided adhesion. The size of the back-up strip should be approximately 20% greater than the joint width and depressed sufficiently to provide the required sealing slot dimensions. Circular cord sections provide a convex face giving an optimum seal configuration, they also overcome any problem of twisting which can occur with square or rectangular sections.  

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For further advice regarding the use of this product, technical support or a quotation please contact us.