How the Backer Rod Performs Its Essential Role In Joining Building Materials

Joints or seams between concrete surfaces must have an expansion joint material to absorb movement and avoid damage to the structure. There are various options for this, available in different materials, sizes and styles. Selecting the most appropriate expansion joint for your project will, therefore, be based upon the environment and the size of the joint. One of the more preferred expansion joints is the backer rod, which in this case is made from extruded polyethylene foam. Its primary use is to fill gaps or voids in a joint, serving as a “backer” before the caulking or chinking material is applied. The process then creates an airtight and watertight seal and a quality finish.

Backer rods may serve a niche purpose, but they are indespensible in the construction industry.

A backer rod is mostly used in flooring or tiling works, but it can also be found in window sealing, countertops, stone works, or decorative wall paneling. Aside from preventing potential damage to either surface, rods also provide additional insulation and can increase the energy efficiency of a building. They even add firmness and accuracy in joining two materials for a neater result. A backer rod serves some very specific construction needs, purposes for which it is indispensable, but has rare use outside of these industries.

Backer rod offers few options when it comes to types as they are mainly available in two choices, namely open cell and closed cell rods. The difference between them lies in how dense the foam is. The open cell type is typically airy and breathable while the closed cell is much denser. Both varieties perform the same function of allowing building materials to move and bend. While sealants remain flexible and stick to the materials sought to be joined, they won’t stick to the backer rod. It’s for this reason that a backer rod is also called a bond breaker.

Though other expansion joints or caulking materials can fill the entire gap, things are much easier and faster with a backer rod, particularly the curing time required for larger projects. In most cases, each project needs special specifications for the best results. Tile flooring in bathrooms, for instance, requires different type of rod than that in walkways or kitchen countertops.

So in order to fully serve your backer rod needs, Alcot Plastics provides you a wide range of backer rods in varying sizes and types.