Control Joint Filler
Control or Expansion Joints
Control joints are intentional linear discontinuities, or cuts, in a structure, like concrete slabs, designed to control where cracks will form. They are strategically placed to prevent random cracking and guide cracks to appear in a straight line within the joint, rather than spreading across the surface.
On the other hand, Expansion Joints often found in concrete, are designed to allow for expansion and contraction of the concrete due to temperature changes, preventing cracking and structural damage. These joints are typically created by cutting into the concrete using a saw, and polyurea can be used to fill and seal them
Backer Rod
Backer rods, often made of closed-cell foam, are used in joint filler to help control the depth of the sealant, ensure proper adhesion, and prevent three-sided adhesion, which can lead to sealant failure. By acting as a "bond breaker" and limiting the amount of sealant needed, backer rods enhance the sealant's flexibility and durability