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How to Protect Metal from Rusting
When considering how to protect metal from rust, there are treatments for roofs. We look at common methods to prevent rust on metal roofs.
Preventing metal from rusting is essential for largescale industrial roofing systems, and there are various methods and approaches. In this blog, we look at how to protect metal from rusting, along with some recommendations on repairing a metal roof.
In the UK, metal roofs are continually exposed to the damp, humid and rainy British weather. Rust is a natural process that occurs when oxygen and moisture reacts with iron present within steel roof sheets. This reaction creates iron oxide, which we know as rust. Without the right approach to maintenance, rust can lead to costly structural damage of a metal roof.
Common Methods to Prevent Rust on Metal Roofs
There are some common materials and methods used to prevent rust, from metal paint to powder coatings. When it comes to metal roofs, rust prevention starts with how the metal sheet has been fabricated and whether it has a factory coating:
- Corrosion-resistant alloys such as stainless steel are commonly used within construction. Although designed to be corrosion-resistant, in reality the rusting process is only slowed down. Stainless steel can still corrode if exposed to certain conditions over time.
- Galvanisation is a process where a zinc coating is applied to protect the steel core of a metal roof sheet from rust. However, when the galvanised metal sheet is cut to size, this can expose the cut edges to rust.
- PVC Plastisol is a factory coating applied when the metal roof sheet is originally fabricated. When the metal sheet is cut to size, the Plastisol coating can be damaged, exposing the cut edges to rust. Weather conditions such as UV rays can also affect the lifespan of this coating, resulting in blisters, peeling and splits.
Regardless of the way a metal roof has been produced or factory coated, regular cleaning and maintenance is essential to ensure structural integrity. There needs to be adequate drainage to prevent standing water, which can accelerate corrosion of exposed areas.
When the surface of a metal roof sheet has deteriorated or the cut edges have been exposed, rust patches can occur. In most cases, a specially designed roof coating or cut edge corrosion treatment can help to avoid costly roof replacements.
Rust Treatment for Metal Roofs: The Best Solutions
Depending on the metal roof sheet’s original coating, rust can arise in various places due to trapped rainwater at the point where the metal sheet overlaps or where there is surface degradation. For damaged metal roof sheets, there are a variety of rust treatments available, especially for corrosion of the cut edges. You can also obtain specific sealants for repairing areas around rooflights on a metal roof to prevent rust from forming.
In the first instance, any rust patches and areas of cut edge corrosion must be addressed. Before any treatment is applied, the surface must be correctly prepared. The surface must then be cleaned and prepared to the Swedish Standard ST3. Any rust patches, dust, dirt and debris need to be removed. Dirt, mould, oil and grease must also be wiped away, and we recommend using the Giromax® Panel Wipe for this purpose.
There are different options for roof coatings. Silicone is a popular coating choice, but it can be susceptible to bird attack and cannot be applied during damp conditions. Silicone coatings can also attract and retain dirt and dust.
Using a specially designed, polyurethane hybrid roof coating is the recommended way to treat and repair a metal roof affected by rust. This type of rust-prevention coating helps to protect the metal roof from impact damage, weather conditions and temperature extremes.
Why Use Giromax Protective Coatings?
Giromax has been developing innovative coatings for decades. Using our own technical team, we have designed highly durable, moisture-tolerant formulas that can be applied during damp conditions, resulting in less contractor downtime.
Our coatings are regularly used to prolong large roofing systems for premises across the UK. We offer guarantees from 15 – 25 years, depending on the product, correct surface preparation and coating application.
When it comes to rust prevention and treatment, our Giromax® Edgecoat offers unparalleled protection for metal roofing. This product was specified for cut edge corrosion repairs of leaking end laps at a large Asda distribution centre in Washington, Tyne & Wear. Giromax® Edgecoat was used to treat and encapsulate the profiled Plastisol/PVDF coated steel roof sheeting, ensuring long-term performance of the roof.
Our products were also specified for The Range retail store in Aylesbury. Giromax® Roofcoat (Metal) and Giromax® Guttercoat were used to extend the lifespan of metal roof sheets, gutters and wall cladding. It had been some time since the original metal sheets and guttering has been fitted and weather damage was causing building problems. Using an airless spray system, the Giromax® products were applied, remedying any issues.
In another example, products within our range were used to refurbish the roof and guttering for the Tate & Lyle Refinery in London. This project involved a roof area of over 10,000m2 and refurbishment of the end-of-life, delaminated surface. Giromax® Roofcoat (Metal) and Giromax® Guttercoat were used to protect the metal roof and guttering system.
Conclusion
To prevent metal from rusting, it’s important to carry out regular maintenance. Use the appropriate cleaning methods to avoid damaging existing factory coatings and apply suitable roof coatings when necessary. Always follow the correct protocols when it comes to surface preparation and coating application to ensure adequate adherence and coverage.
When it comes to treating and protecting a metal roof from rust, Giromax has a team of experienced Technical Services Managers on hand to advise.
For more information or advice on rust prevention, call 01455 558969 or email: sales.orders@giromax.co.uk
Check out the full range of Giromax products.
Source:
(Giromax website, case studies and PP interview)
https://www.cladco.co.uk/blog/post/whats-difference-between-pvc-or-polyester
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How to Protect Metal from Rusting
Managing Director
Preventing metal from rusting is essential for largescale industrial roofing systems, and there are various methods and approaches. In this blog, we look at how to protect metal from rusting, along with some recommendations on repairing a metal roof.
In the UK, metal roofs are continually exposed to the damp, humid and rainy British weather. Rust is a natural process that occurs when oxygen and moisture reacts with iron present within steel roof sheets. This reaction creates iron oxide, which we know as rust. Without the right approach to maintenance, rust can lead to costly structural damage of a metal roof.
Common Methods to Prevent Rust on Metal Roofs
There are some common materials and methods used to prevent rust, from metal paint to powder coatings. When it comes to metal roofs, rust prevention starts with how the metal sheet has been fabricated and whether it has a factory coating:- Corrosion-resistant alloys such as stainless steel are commonly used within construction. Although designed to be corrosion-resistant, in reality the rusting process is only slowed down. Stainless steel can still corrode if exposed to certain conditions over time.
- Galvanisation is a process where a zinc coating is applied to protect the steel core of a metal roof sheet from rust. However, when the galvanised metal sheet is cut to size, this can expose the cut edges to rust.
- PVC Plastisol is a factory coating applied when the metal roof sheet is originally fabricated. When the metal sheet is cut to size, the Plastisol coating can be damaged, exposing the cut edges to rust. Weather conditions such as UV rays can also affect the lifespan of this coating, resulting in blisters, peeling and splits.
