What is a common material used for expansion joint covers?

Brake-formed metal is a common material used for expansion joint covers due to its durability and resistance to various weather conditions and physical stresses. This type of metal is shaped using a brake forming process, which allows for precise bends and folds, creating a strong and protective cover that can effectively accommodate the movement caused by thermal expansion and contraction of building materials. The flexibility and strength of brake-formed metal help to maintain the integrity of the expansion joint while also offering a long-lasting solution that minimizes maintenance and potential damages associated with less durable materials.

In contrast, while wood might be used in some cases, it is not ideal due to its susceptibility to moisture and decay. Plastic can also be used, but it may not provide the same level of protection and longevity as metal. Concrete, while strong, is typically not used for expansion joint covers as it can crack and doesn’t allow for movement in the same way that metals do.