How to design uniqueness with predictability
Naturally, you want to make a COR-TEN® façade look as good as possible during the years. Since COR-TEN® is self-protecting it needs no regular attention or maintenance, as is the case for almost all other façade materials.
The perfect patina
The speed of change and the final color of the steel depend on the atmospheric conditions of a site and the surrounding air quality. Sulfur dense atmospheres will speed up the oxidation process and result in a darker patina. Frequent cycles of wet and dry weather conditions will also speed up oxidation.
- The patina that protects the steel and gives it its distinctive color is formed when COR-TEN® is subjected to alternating wet and dry conditions.
- To maintain an even color, it’s recommended that water can run off freely and not stay on the surface.
- In a sheltered location with damp conditions, COR-TEN® may not adopt the intended color and protective patina.
- Direct contact with earth, snow or vegetation also might affect the color. Therefore COR-TEN® is not recommended for building foundations or socle walls.
- COR-TEN® is sometimes perforated for aesthetic purposes. In these cases, it’s possible that run-off from these holes can affect the color of the patina.
Installing COR-TEN®
- COR-TEN® is very resilient when coming in contact with most other materials. A word of caution is to avoid prolonged contact with wood, copper or other noble metals, chemicals or de-icing salts.
- When installing COR-TEN® on a building, ensure a free airflow together with water running off freely and moisture escaping from the metal’s surfaces and back side. Ventilation space should be full-length and at least 30 mm in width.
- Before installation, COR-TEN® should be stored in dry conditions to ensure a similar patina formation on all steel plates.
- Use screws of acid proof stainless steel in screw connections and EPDM or neoprene gasket to avoid galvanic corrosion.
- For best result, remove welding splashes or any other impurities from the surface.
- Best practice in the case of lap joints is to avoid direct contact between steel surfaces and leave a ventilation gap between steel sheets.
Designing uniqueness with predictability
Bend it. Perforate it. Mix it. There are endless opportunities to bring a natural beauty to the environment it is located in. COR-TEN® steel is now becoming the trend setting material in all aspects of architecture. Buildings that use COR-TEN® steel have been rewarded many times over for innovative and sustainable design.
Profiling COR-TEN® steel sheet
Perforated COR-TEN® steel panels
Mixing COR-TEN® steel
Patina formation process
Apply nature
At first, the steel begins to rust in the same fashion as any other carbon steel, when exposed to wet and dry weather conditions. However, as time passes, the rust layer transforms into a dense patina layer, sealing-off the steel surface, resisting further corrosion. The color changes from fresh, newly developed orange-brown, to light and eventually dark brown. The speed of change and the final color of the steel depend on the atmospheric conditions of a site and the surrounding air quality. Sulfur dense atmospheres will speed up the oxidation process and result in a darker patina. Frequent cycles of wet and dry weather conditions will also speed up oxidation.
COR-TEN® in architecture
Audenasa Headquarters
Amsterdam Klaprozenweg
