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Backer Rods And Sealants: A Timeless Combination
May 30, 2025
Expansion joints are pivotal to ensure the durability of concrete structures. As the name suggests, these joints are purposely left to accommodate expansion and contraction due to temperature changes. Expansion joints ensure there is ample space for construction materials to expand without cracking or compromising structural integrity. Now, these joints cannot be left as they are due to functional and visual reasons. Engineers and contractors rely on backer rods and sealants, a timeless combination, to seal expansion and construction joints. They are also perfect for sealing cracks in walls and pavements.
Backer Rods Help Reduce The Required Sealant
Construction and expansion joints can sometimes be deep and wide. To fill such gaps would require a large quantity of sealant. If you are on a budget or simply do not like wastage, sealants must be used with backer rods. As the name suggests, these rods provide “backing” to the sealant.
By occupying much of the joint or crack, they significantly reduce the need for sealant. What makes backer rod compatible with sealant? Well, the answer lies in the material used to manufacture the soft rods: polyethylene foam.
PE foam is a flexible and durable rod with incredible shape retention ability. It can be squeezed into tight gaps without breaking or tearing. The closed-cell structure means it keeps moisture and water at bay, helping sealant stay intact for many years.
Backer rod and sealant together create an hourglass shape, ensuring better adhesion. The hourglass shape also leaves a gap to accommodate movement due to thermal expansion. Soft rods also prevent sealants from adhering to the bottom of the joint.
Conclusion
Backer rods and sealants are indeed a timeless combination trusted by contractors and engineers alike. Alcot Plastics Ltd. in Guelph, Ontario, manufactures the best PE foam soft rods and supplies to clients across Canada and the US. Call 519.767.2899 to place an order or learn about all we can do for you.
