Corten steel: a living and evolving material

01 — Corten steel

Corten steel changes over time, with the way it develops depending on the surrounding conditions.
It is valued for the protective patina it forms naturally, which gives it excellent weather resistance.

Variations in colour can result from exposure to light and moisture.
We supply products that have not yet oxidised or are only partly oxidised. Their patina may therefore not yet be fully developed or stabilised through passivation.

These variations are particularly noticeable on bent or welded areas, where the patina develops faster. As a result, shades can differ significantly between products from the same batch, or between different surfaces of a single product.

02 — What influences the way Corten develops?

The way the patina forms, adheres to the steel and develops its porosity depends on the composition of the Corten steel and local conditions: temperature, humidity, wind, rainfall and the duration of initial exposure.

03 — Oxidation

An essential part of patina development is the removal of oxides produced by corrosion.

Rainwater helps wash these away by dissolving some of the oxides. The resulting runoff can leave stains on porous surfaces.

👉 We therefore recommend avoiding light-coloured ground surfaces when placing Corten steel items, or using suitable protection.