Expansion joints that are also referred to as compensators mimic those found in our bodies. They are structurally designed to expand and contract in extreme conditions like wind or high temperatures. These joints are placed as structural joint supports and contribute greatly to the overall stability of a structure. They are in most cases used on construction sites to counteract seismic activity as well as help secure the structure while other parts are built around it. They protect against strong winds, dangerous temperatures, and other physical occurrences that could affect the strength of a building and its durability.

Changes in temperature, such as extreme heat, cause the materials in a building to expand, these joints counteract this expansion by contracting. Doing so restores equilibrium, re-compressing the materials within a gap to their original size. When temperatures drop below freezing point, building materials can constrict. The expansion then forces these materials to re-expand.

The ability of expansion joints to widen and narrow regulate structures’ gap sizes, thus reducing the need for repairs and other maintenance procedures. Bridges, sidewalks, railways, and many buildings use them for their stress-relieving qualities. Large air ducts use them to regulate changes in temperature. They are also found in pipes, where they help stabilize movements between separate parts of a structure.

Location varies depending on the structure. In some instances, joints are located in the middle of the project. This is the case with bridges and pipes. Other structures need several throughout. On train tracks, for instance, they can be found every 60 feet or so for temperature regulation purposes. Most are placed at strategic points of strain and pressure in a structure. Ultimately, it is important to choose areas that will need to absorb the most pressure.

Usually made of metal, such as stainless steel, this material allows for a restricted range of motion within a structure, while keeping it intact and under control. Other materials include rubber and concrete. Structure materials include brick for buildings; steel for tracks and pipes and concrete for sidewalks. Regardless of what material is being used, joints can be placed in between portions of several structures for added support. They are malleable and adaptive.

If you are working on a project in a room where the dimensions are just inside the limits for expansion joints you should still install metallic expansion joints, especially if your climate is rather volatile. In a room that is just over 24 feet long, a T-shaped expansion joint should be used between two courses roughly in the middle of the room where the tiling is taking place. Once you determine where the point will be, press it into the adhesive mortar referred to as thinset, making sure to measure to keep the joint at the right distance from the previous course. After properly placing the joint, trowel some thinset over the flange before setting the tile.

Expansion joints have revolutionized the way that many structures are built today. They reduce repair and maintenance costs, thus allowing for a greater diversity of structures to be built. They have proven to have useful qualities that can withstand the many negative effects that weather and other forces of nature pose to a building’s overall safety and stability.