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Why Varnish and Lacquer Fail to Protect Corten Steel: A Closer Look at the Consequences

Nowadays, Corten steel is used as a strong and very attractive material for a wide range of architectural and design projects. However, there are still misconceptions about the best way to protect and maintain Corten steel. Even for some Corten steel fabricators, we have found numerous examples of incorrect applications. One notable misconception lies in the use of varnish or lacquer as a protective coating. In this article, we will show the adverse effects of this misconception and present the best solutions for protecting Corten steel.

The Downside of Corten Varnish and Lacquer

Prone to mottling finishes: Microscopically, weathered Corten steel is not smooth but rather characterized by grooves and holes, creating a rough surface. Varnish and lacquer struggle to adhere completely and evenly to this textured surface. Over time, areas with weaker coating thicknesses become more susceptible to erosion, leading to an uneven, patchy finish. You can even clearly see on the surface the brush strokes and brush tracks from when the varnish was first applied.

Corten steel varnishes and lacquers

Poor Durability: The inherent weakness of varnish and lacquer post-drying offers limited protection against erosion and UV radiation. These coatings fail to provide lasting defense against Corten steel's continued weathering process. Within a short period, the surfaces coated with varnish and lacquer deteriorate, exposing the Corten steel to further natural erosion.

Corten steel varnishes and lacquers

Maintenance Dilemma: Property holders are often faced with two undesirable options once the protective period of varnishes and lacquers ends. They must either undertake frequent repainting and costly maintenance or allow unsightly signs of erosion to develop, ultimately necessitating expensive replacement or restoration.

Corten steel varnishes and lacquers

A Better Option: BROMOCO Corten Solutions

Exceptional Sealing and Coverage: Applied after Corten steel has achieved a desired level of weathering, BROMOCO's solution effectively seals the material, halting further weathering processes and preserving its appearance. BROMOCO's CT-7571 Solutions are highly ductile, capable of covering every microscopic groove and hole in weathered Corten steel, ensuring uniform protection across the surface.

Erosion Resistance: BROMOCO's solution offers long-lasting protection against harsh weather conditions, including acid rain, salt, graffiti, bird droppings, oxidation and UV rays, ensuring Corten steel retains its integrity and aesthetic appeal.

Lasting Protection: Backed by a 5-year guarantee, BROMOCO's projects have demonstrated effectiveness beyond the warranty period, providing more than 10 years assurance of enduring protection for Corten steel structures.

Corten Steel Cleaning and Restoration Solutions
Corten steel sealing and protection

After a difficult restoration and considerable expense to the owner, BROMOCO has finally restored the Corten project to its normal level and applied BROMOCO protective coatings. If the right protective coating had been chosen from the start, these high costs would not have been incurred, would they?

BROMOCO's Corten Solutions are specifically designed to withstand the challenges posed by the UK's inclement weather conditions. By choosing BROMOCO, holders can ensure long-lasting protection for Corten steel structures. Eliminates the need for frequent maintenance, saving both time and resources for property owners.

For more caseshow & information, please check the product document.


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