How long does Corten Steel last?

The lifespan of corten steel is determined by a variety of factors. The distinctive oxide coating actually protects the steel from further oxidation and degradation. The steel is delivered new in a grey/blue state, with no protective coating. Once installed, it begins to rust.

With mild steel, the rust coating flakes off, exposing the steel underneath and meaning that the steel slowly disappears. The rust coating on corten steel is much more stable, and will not flake off. This means that the steel will last much longer than mild steel, and will not need to be replaced as often.

Our steel is either 2mm or 3mm thick, which is enough to ensure a 50 year lifespan in most environments. In more corrosive environments, such as coastal areas, the steel may corrode at a faster rate. In addition, steel that is buried, such as with our posts or pegs, will corrode at a faster rate than steel that is exposed to the air. This is because the oxide coating is not able to develop properly as the wet/dry cycle is disrupted. To improve the lifespan of steel exposed to soil in this way, such as with the steel that is facing the soil in our planters or retaining walls, you can either allow the steel to rust before filling in the soil, or cover the steel with a bitumen adhesive in order to provide a protective coating for the steel.