How to Properly Paint Galvanised Steel

Dangle Academy • 27 June 2023
galvanised floor plate

Galvanised Paint for Steel

Advantages of Zinc Paint Disadvantages of Zinc Paint
Good adhesion to galvanised steel Can be expensive
High resistivity to bi-metallic corrosion Requires proper ventilation when applying due to strong fumes
Dries quickly Not suitable for painting bare steel surfaces


How to Properly Paint Galvanised Steel - Expert Guide


Learn the proper way to paint galvanised steel with our expert guide. Follow these steps for a long-lasting and durable finish that stands up to the elements.


Painting galvanised steel can be a tricky process as it requires a specific approach to ensure the paint adheres properly and lasts . Galvanised steel has a protective layer of zinc coating, and any paint applied directly on it can peel off easily. ISO 12944 is the globally recognised standard for the corrosion protection of steel structures by protective paint systems.


With our expert guidance, you'll learn everything you need to know about how to properly paint galvanised steel, from understanding the material to curing and maintaining painted galvanised steel. Read on to discover the best techniques for painting galvanised steel and get your job done right, first time, as re-work is even more costly!



Painting Galvanised Steel


Painting galvanised steel is simply a type of steel coated in a layer of zinc to protect it from corrosion. This coating creates a barrier that prevents the steel from coming into contact with moisture and oxygen over time, which are the two primary causes of corrosion. While galvanised steel is somewhat resistant to corrosion, it is still susceptible to bi-metallic corrosion when it comes into contact with bare steel or other metals.


Bi-metallic corrosion occurs when two dissimilar metals come into contact with each other in the presence of moisture and oxygen. When this happens, an electrochemical reaction takes place, which causes one of the metals to corrode faster than normal, this is often called a "anode". In the case of galvanised steel, if it comes into contact with bare steel, the zinc coating will corrode faster than it normally would, leaving the steel vulnerable to corrosion, unless expert advice is sort.



Understanding Galvanised Steel and Bi-Metallic Corrosion


In order to prevent bi-metallic corrosion, it is important to use the proper isolation methods when working with galvanised steel. This can include using gaskets or washers made from materials like rubber or nylon, that are compatible with both the galvanised steel and the other metal it will come into contact with. It is also important to avoid leaving any bare steel exposed when working with galvanised steel, as this can create a direct path for bi-metallic corrosion to occur.


Tip: When working with galvanised steel, it is a good idea to use tools, fasteners, and other materials that are specifically designed for use with galvanised steel, as these will be less likely to cause bi-metallic corrosion.


It is also important to note that while galvanised steel is partly resistant to corrosion, it is not completely immune. Over time, the zinc coating can wear away, leaving the steel vulnerable to corrosion. For this reason, it is important to monitor galvanised steel for signs of wear and damage and to address any issues as soon as possible to prevent corrosion from occurring.

Note: If you are unsure about the condition of your galvanised steel or how to properly maintain it, it is always best to consult with a professional industrial painting company, like Dangle to ensure that your steel is properly protected.


Painting Newly Galvanised Steel


The process of painting newly galvanised steel, is similar to that of aged galvanised steel, so it is important to properly prepare the surface first as you would with any substrate. Failure to do so could result in poor adhesion and premature paint failure, leading to costly rework and maintenance.


It is essential to remove any contaminants, including oil, grease, and dirt, from the surface. This can be accomplished using a mild detergent or solvent and a soft-bristled brush or sponge. Rinse thoroughly with clean water and allow the steel to dry completely.


Next, inspect the surface for any defects, such as rough spots and sharp edges. Surface imperfections are usually defined in ISO 8501-3 with a rounding of sharp edges to no less than 2mm. Uneven surface imperfections should be smoothed out using a suitable power tool like a grinder or a wire brush to ensure an even surface before painting.


It is also important to consider the age and condition of the galvanised coating if not newly galvanised. If the steel has been exposed to the elements for an extended period of time, the zinc coating may have oxidised or developed a white powdery film known as "white rust." This must be removed using a chemical or mechanical treatment prior to painting, if not the paint will not adhere correctly and eventually peel off.


Consult with our professional industrial painters for the best course of action.


Finally, it is recommended to use a high-quality primer specifically designed for galvanised steel. This will enhance adhesion and help mitigate corrosion. Always follow the manufacturer's instructions for the best results.



Choosing the Right Paint for Galvanised Steel


Choosing the right paint for galvanised steel is crucial to ensure maximum longevity of the painting job. Not all paints work for galvanised steel, and selecting the wrong paint can lead to early peeling and flaking.


The ideal type of paint for galvanised steel is zinc paint. Zinc paint is epoxy-based and has a high resistivity to bi-metallic corrosion, which occurs due to the presence of bare mild steel in close proximity to the galvanised steel.


Zinc paint also has good adhesion properties, which helps in ensuring the paint sticks firmly to the galvanised steel surface.


It is important to note that other types of paint, such as oil-based or acrylic paints, are not recommended for galvanised steel painting. These paints can lead to peeling or flaking of the paint layer due to poor adhesion to the galvanised surface no matter how well the surface prepared.


When choosing the right paint for galvanised steel, it is also important to select a paint that matches the intended use of the painted steel. For example, if the painted steel will be exposed to harsh weather conditions, it is recommended to choose a paint that has a high UV resistance. The selection of coating systems is also defined in ISO 12944-2 and ISO 12944-5.



Paint for Galvanised Steel


Now that the galvanised steel has been properly cleaned and prepared, and the right paint has been chosen, it is time to apply the paint to the galvanised steel. Follow these steps to ensure an even and long-lasting coating:


  1. Apply the paint in thin coats using a brush, roller, or spray gun. It is better to apply several thin coats than one thick coat, as thick coats can result in drips, sags, and an uneven finish, as well as increasing the curing time.
  2. Allow each coat to dry completely before applying the next. The drying time will depend on the type of paint and the temperature and humidity of the environment. Check with the paint  manufactures technical data for specific instructions.
  3. If necessary, lightly sand the surface between coats to ensure optimal adhesion, if not you really rely on a process called chemical cohesion, which in simple terms is the chemical bonding of the two coats of paint.
  4. Avoid painting in direct sunlight or when the surface is hot to the touch, as this can cause the paint to dry too quickly and result in a poor finish, with coating defects likely to occur.
  5. Use a high-quality brush or roller to avoid leaving brush marks or roller sleeve stipple. If using a spray gun, follow the manufacturer's instructions for use and maintenance.
  6. Apply enough paint to cover the surface completely, but avoid overworking the paint, as this can result in brush marks, roller sleeve stipple, or an uneven finish.
  7. Repeat the process until the desired number of coats has been applied. In general, two to three coats are sufficient for most applications, however always follow the coating specification and manufactures technical data sheets.


Note: Remember to use caution when working with paint, especially when using a spray gun. Wear protective clothing and a respirator if necessary, and take appropriate safety measures to avoid inhalation, ingestion, or contact with skin and eyes.


"Applying paint to galvanised steel requires patience and attention to detail. Take your time and follow the manufacturer's instructions for the best results." - Simon, Industrial Painting Expert & Author


Maintaining Painted Galvanised Steel


After painting galvanised steel, it is vital to allow the paint to cure properly. This ensures that the paint adheres to the steel surface and provides long-lasting protection against corrosion and other forms of damage.


Typically, curing time for paint on galvanised steel ranges from 24 to 48 hours. However, the exact curing time may vary depending on the type of paint used and environmental conditions such as temperature and humidity. It is crucial to follow the manufacturer's instructions for curing time to achieve the best results.


Proper maintenance for painted galvanised steel


After curing, the painted galvanised steel requires proper maintenance to ensure it remains in good condition. Regular cleaning and inspection can help to identify any defects or issues that may arise.

When cleaning painted galvanised steel, take care to avoid harsh chemicals or abrasive materials that may scratch or damage the surface. Instead, use a soft cloth or sponge with mild soap and water to gently clean the surface. It is also essential to avoid using high-pressure water jets or steam cleaning, which can damage the paint and expose the steel to corrosion.


Inspect the painted galvanised steel regularly for signs of damage, including peeling, cracking or rusting. Promptly address any issues to prevent further damage and ensure the steel continues to provide optimal coating protection.


Benefits of properly curing and maintaining painted galvanised steel


By properly curing and maintaining painted galvanised steel, you can enjoy a range of benefits, including:

  • Long-lasting protection against corrosion and other forms of damage
  • Cost savings by avoiding the need for frequent maintenance or replacement of damaged or worn steel
  • Enhanced aesthetics for a more professional appearance
Proper maintenance of painted galvanised steel is crucial for ensuring optimal performance and longevity. By following the manufacturer's instructions for curing time and regularly cleaning and inspecting the surface, you can enjoy long-lasting protection against corrosion and other forms of damage.


Common Mistakes to Avoid when Painting Galvanised Steel


Painting galvanised steel requires special attention to detail to ensure a long-lasting and durable finish. However, there are several common mistakes that can undermine your efforts and lead to disappointing results.


Here are some pit-fall things to avoid:


Skipping preparation - Newly galvanised steel requires thorough cleaning and preparation before painting to remove any surface contaminants that can interfere with paint adhesion.


Using the wrong type of paint - Zinc paint is recommended for painting galvanised steel because it is designed to adhere to zinc-coated surfaces. Using a different type of paint can result in poor adhesion and premature peeling.


Overlooking bi-metallic corrosion - If galvanised steel comes into contact with bare steel or other metals, bi-metallic corrosion can occur. This can undermine the integrity of the paint and lead to rust formation.


Not allowing sufficient drying time - Paint needs adequate time to dry before curing. Rushing the process can cause the paint to bubble, crack, or peel prematurely. Always consult with the paint manufactures technical data sheet.


Applying too thin or too thick a coat - Failure to apply paint evenly can lead to an unattractive finish and poor adhesion. Applying too thin a coat can also result in inadequate protection, while applying too thick a coat can cause the paint to crack or peel.


By avoiding these common mistakes, you can help ensure that your painted galvanised steel surfaces look great and provide long-lasting protection against corrosion and wear.



Benefits of Hiring Professional Industrial Painters


While painting galvanised steel may seem like a simple task, it requires expertise and experience to ensure a long-lasting, quality finish. Hiring professional industrial painters from Dangle for your galvanised painting needs comes with several benefits:


  1. Expertise: Professional industrial painters that have the knowledge and skills to properly prepare and paint galvanised steel, ensuring the finish is durable and resistant to corrosion.
  2. Efficiency: With specialised tools and techniques, our professional industrial painters work quickly and efficiently, minimising downtime for your business.
  3. Quality Results: Dangles professional industrial painters use top-quality paints and coatings, ensuring a smooth and even finish that will last for years to come.
  4. Safety: Industrial painting can be dangerous, with hazards such as fumes and working at heights. Professional painters are trained to follow safety protocols and have the necessary equipment to minimise risk.
  5. Cost Savings: While it may seem more expensive upfront to hire our professional industrial painters, their expertise and efficiency can actually save you money in the long run by ensuring a long-lasting finish that won't require frequent touch-ups or repairs.


When searching for a professional industrial painting company, be sure to choose one with experience in painting galvanised steel and a reputation for quality, safety and training.



Why Choose Dangle's Academy


Here at Dangle, we pride ourselves on offering a wide range of professional and comprehensive inspection, access, coatings, and composite (IACC) industrial services and training courses to cater to the needs of both the private and public sectors. Our dedication to providing high-quality work at height solutions and training has helped us establish a strong reputation in the industry.


With a team of highly skilled and experienced professionals, we are committed to delivering exceptional results that not only meet but exceed our clients' expectations. Our on-site working at height services are designed to minimise maintenance costs in the long and short-term, allowing our clients to save on valuable resources.


Located in Belfast, Northern Ireland, our headquarters serve as the centre of our operations across Ireland. However, we also have a Dangle office based in Scotland, ensuring that we can extend our services to a wider clientele across the United Kingdom. No matter where you are located, our team is always ready to assist you with your industrial maintenance or training needs.


If you would like to learn more about how our dedicated team can help you, we encourage you to get in touch with us today. Our friendly and professional staff are always available to provide you with the information and support you require.


Contact us now to discover the Dangle difference and let us be your trusted partner in meeting your industrial service and training needs today.




FAQ


  • Q1. Can I paint galvanised steel without any preparation?

    No, you cannot. Proper preparation is crucial for successful painting of galvanised steel. The surface needs to be cleaned, degreased, and etched or anchor profiled before painting to ensure adhesion.

  • Q2. What type of paint should I use for galvanised steel?

    You should use a paint that is specifically designed for galvanised steel. Zinc-rich coatings are the best choice as they offer excellent adhesion to the surface of the steel.

  • Q3. Can I use any paint primer on galvanised steel?

    No, you cannot. It is crucial to use a primer that is specifically designed for use on galvanised steel. Regular primers won't adhere to the surface and will lead to paint failure.

  • Q4. Can I paint over existing paint on galvanised steel?

    If the existing paint is in good condition, you can paint over it after cleaning and degreasing the surface. However, if the existing paint is peeling or flaking, it needs to be removed before applying new paint.

  • Q5. Can galvanised steel be painted in any color?

    Yes, it can. You can choose any color you want for your galvanised steel. However, it is best to use light or reflective colors to avoid excessive heat build-up. Dark colors tend to absorb more heat, which can cause the steel to warp or buckle.

  • Q6. How long does painted galvanised steel last?

    The lifespan of painted galvanised steel depends on many factors, such as the type of paint used, the quality of the application, and the environment it is exposed to. However, with proper maintenance, painted galvanised steel can last for many years.

  • Q7. What maintenance does painted galvanised steel require?

    Painted galvanised steel needs to be regularly cleaned to maintain its appearance and prevent corrosion. Mild soap and water can be used to clean the surface. Avoid using harsh chemicals or abrasive cleaners as they can damage the paint.

We'd Love a Share...

You might also like

A man in a hard hat is sitting in a confined space hole with a ladder.
by Dangle Academy 18 April 2025
Why More Companies Are Choosing Rope Access for Confined Space Work In today’s industrial landscape, confined space work remains one of the most challenging and high-risk tasks for companies across a wide range of sectors. Whether it’s cleaning inside storage tanks, inspecting silos, or conducting maintenance in utility tunnels or petrochemical plants, the complexity, danger, and logistical hurdles of confined space operations demand nothing short of excellence in planning, access, and execution. Traditionally, this type of work required extensive scaffolding, large teams, and lengthy setup times — often resulting in increased cost, risk, and downtime. But that’s changing. More companies across Ireland and the UK are turning to Dangle and rope access in confined spaces as a faster, safer, and more cost-effective solution for confined space work . In this article, we’ll explore why rope access is becoming the go-to method for confined space work , and how it enhances safety and efficiency. What is Confined Space Work? A confined space is defined as any fully or partially enclosed space that: Is not designed for continuous occupancy Has limited entry and exit points (usually only one) May pose health and safety risks such as lack of oxygen, toxic gases, or physical hazards Examples include: Storage tanks Boilers Silos Incinerators Underground vaults Utility shafts Vessels Sewers and pipelines Confined space work involves entering these environments to carry out inspections, repairs, cleaning, welding, painting, or maintenance. Given the physical restrictions and potential hazards, it’s classified as high-risk confined space work and must comply with stringent safety regulations in Ireland, the UK and across the EU. Rope access is proving to be a transformative approach in the realm of confined space work . This innovative method is rapidly gaining traction among companies seeking to overcome the traditional challenges associated with confined space operations. The appeal lies in its ability to deliver enhanced safety, efficiency, and cost-effectiveness. The Traditional Challenges of Confined Space Work Performing confined space work presents several operational and safety challenges for asset owners: Limited mobility and access Poor ventilation and oxygen-deficient atmospheres Risk of toxic exposure or flammable gases Difficulties in rescue operations Cumbersome entry methods using scaffolding or mobile platforms These factors not only increase risk but also drive up operational costs and project timelines. In many cases, companies must halt or limit production during confined space entry, resulting in revenue losses. Rope Access: A Modern Solution for Confined Space Challenges Rope access is revolutionising the way companies approach confined space work . Instead of relying on large, immobile access structures, technicians use ropes, harnesses, lanyards and fall-arrest systems to safely enter and operate within tight spaces. The method is rooted in climbing and caving techniques but has evolved into a globally recognised safe system of confined space working developed by organisations such as IRATA ( Industrial Rope Access Trade Association ) . How Rope Access Works in Confined Spaces Rope access in confined space work typically involves: Pre-entry permit to work, risk assessment and atmospheric testing like gas testing Installation of rope access and retrieval systems Certified technicians using two-rope systems (working line + backup line) Continuous monitoring and standby rescue teams Use of communication systems, gas monitors, and RPE and PPE This method allows highly skilled rope access technicians to carry out precise work in confined environments with greater mobility, speed, and control. Why Companies Are Switching to Rope Access for Confined Space Work Unmatched Safety Standards Safety is paramount in confined space work . With rope access, the entire operation is built around redundant systems and rigorous safety protocols. • Dual-rope system provides fall protection and redundancy • Certified technicians undergo regular training and assessments • Pre-installed rescue systems allow for immediate extraction • Gas detection and atmospheric monitoring are continuous According to industry data, rope access has one of the lowest incident rates in the industrial sector — a testament to its controlled, methodical approach. Rapid Deployment and Project Turnaround Rope access technicians can mobilise quickly, often completing setup within hours instead of days. There’s no need for large scaffolding crews or heavy equipment. • Faster setup and teardown • Minimal interruption to plant operations • Jobs completed in a fraction of traditional timelines This speed translates to reduced downtime, which is critical in sectors such as oil & gas, energy, pharmaceuticals, and utilities. Operational Cost-Effectiveness Rope access significantly reduces the overall cost of confined space work by: • Eliminating scaffolding and platform hire • Requiring smaller, more skilled teams • Reducing setup and access time • Minimising operational downtime For companies seeking efficient maintenance without breaking the budget, rope access offers an exceptional return on investment, contact Dangle for further advice or to receive a free no obligation quote for your next project. Versatility and Flexibility Rope access adapts to even the most complex and awkward confined space work — whether horizontal, vertical, or with irregular internal structures. From underground tanks to vertical silos, rope technicians can position themselves exactly where needed using only their skills, minimal tooling and equipment. • Navigate complex internal geometries • Perform precision tasks (e.g., welding, NDT, inspection, painting, cleaning) • Easily integrated with confined space work and rescue protocols This flexibility allows rope access to support a diverse range of industries and maintenance tasks. Built-in Rescue Readiness One of the biggest concerns in confined space work is emergency rescue. Dangle's rope access teams are not only trained in confined space entry — they’re also certified in casualty rescue, with dedicated standby technicians on every job. At Dangle, all technicians are trained in: • Rope-based confined space rescue • Use of winch and tripod systems • CPR and first aid for high-risk environments This means your project doesn’t just meet legal safety obligations — it exceeds them. Sectors Benefiting from Rope Access in Confined Spaces Energy & Utilities • Inspections inside turbines, boilers, and tanks • Emergency repairs during shutdowns • Cleaning of heat exchangers Pharmaceutical & Food Processing • Internal cleaning and integrity checks of vessels • Maintenance in sterile, hard-to-access environments Manufacturing • Silo and hopper cleaning • Welding repairs and corrosion protection Water & Wastewater Treatment • Accessing underground chambers and tanks • Structural inspections and leak testing Oil & Gas / Petrochemical • Confined space NDT in hazardous atmospheres • Gas monitoring and ATEX-compliant work methods Rope Access in Ireland: Why It’s Gaining Momentum With a growing focus on safety, compliance, and environmental responsibility, companies are increasingly turning to Dangle's rope access for confined space work . Whether in the green energy sector, industrial hubs like Cork and Limerick, Dublin’s expanding infrastructure or Belfast’s shipbuilding and maintenance at Harland & Wolff , the need for efficient confined space access is rising — and rope access is leading the way. The method’s efficiency and safety benefits have led to its widespread acceptance in industries that demand stringent safety standards and quick turnaround times. Rope access allows these companies to conduct thorough maintenance and repair operations without extensive downtime, thereby boosting productivity and ensuring compliance with industry regulations. Future Trends: The Integration of Technology and Rope Access The future of confined space work lies at the intersection of rope access and smart technologies. At Dangle, we’re investing in tools such as: Wearable gas detectors Confined space entry monitoring systems Breathing apparatus Digital work logging Drone collaboration for external assessments Combining rope access with technology ensures your confined space projects are not only safe and compliant — but also future-ready . Why Choose Dangle’s Academy? Here at Dangle , we pride ourselves on offering a wide range of professional and comprehensive inspection , access , coatings , and composite (IACC) industrial services and training courses to cater to the needs of both the private and public sectors. Our dedication to providing high-quality work at height solutions and training has helped us establish a strong reputation in the industry. With a team of highly skilled and experienced professionals, we are committed to delivering exceptional results that not only meet but exceed our clients' expectations. Our on-site working at height services are designed to minimise maintenance costs in the long and short-term, allowing our clients to save on valuable resources. Located in Belfast, Northern Ireland, our headquarters serve as the centre of our operations across Ireland. However, we also have a Dangle office based in Scotland , ensuring that we can extend our services to a wider clientele across the United Kingdom. No matter where you are located, our team is always ready to assist you with your industrial maintenance or training needs. If you would like to learn more about how our dedicated team can help you, we encourage you to get in touch with us today. Our friendly and professional staff are always available to provide you with the information and support you require. Contact us now to discover the Dangle difference and let us be your trusted partner in meeting your industrial service and training needs today.
A group of people are climbing ropes in a building.
by Dangle Academy 7 April 2025
Essential Guide to Rope Access Training: Benefits, Techniques, and Certification for Safe and Effective Hight Work.
The sun is shining through the clouds on a bridge
by Dangle Academy 24 March 2025
Bridges are crucial for the UK’s transport and economy, but environmental factors, traffic, and aging require regular inspections and maintenance for safety.
More posts

Book a Service Today