Tips for Choosing the Right Coating System for Australian Climate
From arid deserts to coastal salt spray and industrial zones, Australia’s landscapes are truly breathtaking. At times, however, these environments can be extremely harsh on infrastructure assets, concrete, and steel. If the systems are not tailored to their specific environments, coatings can get compromised quickly by chemical exposure, UV degradation, and corrosion. This is why long-term durability, safety, and compliance of industrial coatings demands selection of the right protective coating.
At Coating Management Solutions, we have a track record of assisting clients across Australia in selection, testing, and inspection of coating systems capable of withstanding the toughest conditions.
Here are a few tips to get your coating system right.
Understanding the Environment
Environmental classification is the starting point in any coating specification. Based on corrosion severity, AS 2312.1 and ISO 12944 categorises environments from C1 for very low to CX for extreme. Here are a few examples.
- Industrial regions (C4–C5): chemical-resistant coatings are required for preventing damage caused by pollutants and chemicals.
- Coastal and marine zones (C5–CX): These environments tend to accelerate corrosion due to the presence of humidity, high salt concentration, and UV radiation.
- Desert and arid environments: The main threats in these areas are UV degradation and wind-borne abrasives.
- Tropical or inland humid areas: These environments require moisture-tolerant and antifungal systems to prevent the impact of moisture and biological growth.
A precise environmental assessment makes it possible to choose a coating system that continues to deliver desired performance throughout its service life.
Well Defined Substrate and Service Life
Whether steel, aluminium, concrete, or galvanised surfaces, coating selection is greatly influenced by the substrate. Cathodic protection, barrier protection, and chemical resistance are critical for steel structures. On the other hand, concrete requires coatings capable of dealing with porosity, moisture ingress, and carbonation.
Service life expectation is another key factor. For example, a 5-year system may be sufficient for temporary construction element. However, a marine piling or bridge may require 25 years or more. When a longer service life is required, a multi-layer system is recommended along with superior surface preparation. Also, the system must be thoroughly inspected at each stage.
Surface Preparation
When the surface is inadequately prepared, no coating is likely to perform well. In fact, almost 80% of coating failures can be attributed to poor surface preparation.
For steel, it is possible to ensure the correct anchor profile for adhesion by abrasive blasting to standards such as AS 1627.4 / ISO 8501-1 Sa 2½. Before application, concrete must be dry, clean, and mechanically profiled.
During surface preparation, it is also important to control and document environmental conditions such as temperature, humidity, and dew point.
Appropriate Coating System
Today’s advanced coating systems are designed to address specific threats. Some of these include
- Epoxy coatings are recommended for marine and industrial environments because of their chemical and abrasion resistance.
- Polyurethane topcoats help maintain gloss and colour stability by providing protection against UV and weathering.
- Zinc-rich primers are ideal for coastal or offshore structures as they can offer galvanic protection for steel.
- Moisture-cured urethanes are effective for damp or high-humidity sites where surface dryness is difficult to achieve.
- Fluoropolymer and polysiloxane systems are extremely effective as high-performance options for environments that demand superior weatherability.
If you want to find out more about choosing the right coating system for your specific requirement, please contact us at Coating Management Solutions.