How long will Corten Steel last?

Thicknesses of modest specification [2.0mm or 3.0mm] are perfectly fit-for-purpose for + 25 years longevity in most environments/applications. An additional 1.0mm thickness is needed to mitigate the forecast material loss over a 40-year lifespan. The majority of weathering steel types require cycles of wet and dry weather to develop and oxidise.

The weathering steels, known by their trademark COR-TEN steel, are a series of steel alloys that have been developed to eliminate the need for painting and form a stable rust-like appearance if exposed to the weather for several years.