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The Three Types of Backer Rods

November 02, 2022

The Three Types of Backer Rods

Backer rods, also known as foam rods, are an essential tool for any caulking project, yet many people are unaware of their existence, let alone their purpose. In this blog post, we will explore three types of foam rods and their applications so that you can be better informed the next time you take on a caulking job. A foam rod is used to fill large gaps before caulking. It is available in different diameters and lengths and can be used for both indoor and outdoor projects. There are three main types of foam rods: closed-cell, open-cell, and bi-cellular. Each type has its own advantages and disadvantages that make it better suited for certain applications.

Unique specifications of each type of foam rods

Open-cell backer rods

Open-cell foam rods are made of polyethylene and have a round cross-section. The cells are not interconnected, which allows the rod to compress easily. Open-cell rods are used to fill gaps and voids before applying sealants or adhesives.

They have a few advantages over closed-cell rods. They are easier to compress, so they can conform to irregular shapes better. They also absorb less sealant, so there is less risk of the sealant weeping out of the joint.

One downside of an open-cell foam rod is that it can be difficult to remove if you need to make repairs. The cells can collapse under pressure, making it hard to get a good grip on the rod. Another downside is that the open-cell rod is not as strong as the closed-cell rod, so it may not provide as much support for the sealant joint.

Closed-cell backer rods

Closed-cell foam rods are made of closed-cell foam that is inserted into cracks or joints to provide support for sealants. The foam rod prevents the sealant from sagging or stretching, and it also provides a consistent thickness for the sealant. Closed-cell rods are available in different diameters to fit the width of the joint or crack. One of the significant benefits of closed-cell rods over their open-cell counterparts is that they can be removed easily for repairs. Closed-cell rods are also much stronger than open-cell rods.

Bi-cellular backer rods

Hybrid or bi-cellular rods offer the best of both worlds. The surface of the bi-cellular rod contains closed-cell and open-cell material. It can be easily compressed to fit into tight spaces like an open-cell foam rod. At the same time, it also resists moisture and water similar to its closed-cell counterpart. Bi-cellular foam rods are ideal for applications where bubbling concerns are critical.

No matter what kind of backer rod you are looking for, your search ends here. Alcot Plastics Ltd. is a leading manufacturer of soft backer rods and other polyethylene foam products like screening splines and pool noodles. Call us today to get a free quote on our products.