Corten steel - What you need to know!

Corten steel - weatherproof structural steel with great potential

Corten steel is trendy and is increasingly being used around the home and garden. Whether in the form of privacy screens, garden decorations, or raised beds: Corten steel scores with its exceptional resistance to weather influences and its unique appearance. We explain exactly what this structural steel is all about in this guide.

What is Corten steel and where does the name come from?

Corten steel was already used for the construction of bridges in the 19th century. Even then, this structural steel proved particularly useful because it easily withstands weather conditions – even though it is uncoated.

The exact trade name is COR-TEN® steel. The term is a combination of COrrosion resistance (rust resistance) and TENsile strength (tensile strength).

ELEO CorTen steel privacy screen in front of the house entrance

Trendy for home and garden: CorTen steel privacy screens like the ELEO Reno privacy screen. © ELEO

Is there a difference between steel and Corten steel?

In its pure form, Corten steel is a structural steel. However, copper, chromium, and nickel are added to it. This results in its special corrosion-resistant properties. Corten steel forms a special barrier layer when exposed to weather conditions—alternating dryness and moisture. This special rust patina is characteristic of Corten steel and makes it so durable. Although structural steel can also rust, Corten steel does not.

We have summarized the properties and advantages of Corten steel here:

Surface	Corten steel has a unique orange-brown color and a rough, cracked surface.
Corrosion-resistant	Corten steel has excellent corrosion resistance, making it ideal for outdoor use.
Formability	Corten steel has high formability and is therefore easy to work with.
Durability	Corten steel is very durable and can last for many years without significant changes or damage.
Environmental friendliness	Corten steel is environmentally friendly and can be easily recycled.
Costs	Corten steel is a relatively expensive material, but the investment is worthwhile due to its unique properties.

Why is Corten steel special?

The rust barrier layer that forms on the steel is solid and acts as a kind of protective film for the material, preventing it from rusting and can become unstable. This is ensured by the oxide layer that forms on the surface. This layer is dense and almost impermeable to oxygen. Thanks to these properties, Corten steel is also frequently used in architecture.

The color of the rust patina is constantly changing and depends on the weather conditions. It can develop from bright orange tones to brown tones.

ELEO Corten steel privacy screen in detail

Corten steel can take on a variety of colors – from bright orange to dark brown. © ELEO

When you should seal Corten steel

It may initially seem illogical to seal Corten steel, as the structural steel is weatherproof. However, if it is used in the home and garden – for example, as privacy screens on the patio – sealing can be a good idea.

Reasons for sealing include:

The rust patina may rub off a little at first, leading to discoloration on the surfaces.
A certain state of rust should be preserved – for example, because the color of the patina is particularly pleasing and should not change further.