Expanded metal is made by slitting sheet metal (galvanized steel, aluminum, painted or unpainted) and then stretching it to achieve varying degrees of openness and translucency. Expanded metal is commonly used for screening, stair treads, infill, cladding, aesthetic and other purposes. On occasion, expanded metal is considered as a less costly substitute product to metal fabric, also known as architectural mesh, metal mesh or wire mesh.
While expanded metal may provide an initial material cost advantage, architectural metal fabric is often a better choice for long term exterior applications. For example, one major drawback of expanded metal is corrosion resistance. Galvanized sheet metal is left unprotected along the edge of each perforation, leaving these areas vulnerable to rust and corrosion. Because exterior architectural metal fabric is woven of stainless steel, corrosion resistance is of little or no concern.
Additionally, expanded metal lacks the unique texture of architectural metal mesh. This is because metal fabric is actually woven like a fine fabric, while expanded metal is simply a sheet of metal that has been slit and then stretched to achieve the desired pattern. Depending on the application, architectural metal fabric may be a better choice than perforated metal or expanded metal.