What You Need to Know About the NCC 2022 Changes to Corrosion Protection
The National Construction Code (NCC) 2022 update introduces significant changes to the corrosion protection standards for structural steel, impacting the way Australian construction projects are designed and executed. These changes aim to enhance the durability and longevity of steel structures, ensuring they withstand the test of time.
We’re here to help you navigate these changes and understand how they apply to your projects.
What Are the New Changes?
The NCC 2022 introduces updates to corrosion protection under Clause 6.3.9 of the Housing Provisions Standard, replacing Clause 3.4.4.4. The main changes include:
- Alignment with AS4312:2019: Environmental classifications for corrosion now align with the AS4312 standard, providing a more accurate categorisation of atmospheric corrosivity zones in Australia.
- Enhanced Durability Requirements: All structural steel elements must meet a minimum design life of 15 years, ensuring long-term protection and performance.
- Updated Corrosion Tables: The new provisions include more detailed guidance and additional options for protective coatings based on location and environmental exposure.
These updates apply to construction projects submitted for council or certifier approval after May 1, 2024.
Corrosion Zones and Protection Needed
For details about what this means, please refer to the below graphic:
Why Were the Changes Made?
The Building Codes Committee’s review highlighted outdated environmental categories and assumptions in the previous corrosion protection tables. The updated code ensures:
- Improved Accuracy: Corrosion zones better reflect actual environmental conditions.
- Increased Safety and Durability: Enhanced protective measures reduce the risk of structural failure due to corrosion.
- Modern Standards: Alignment with AS4312 ensures best practices are maintained across the industry.
How Does Steel Builders Ensure Compliance?
At Steel Builders, compliance and quality are our highest priorities. To meet the new NCC 2022 standards, we’ve implemented a new compliant paint system for structural steel applications. This system provides superior durability, with a 25+ year lifespan to first maintenance—far exceeding the code’s minimum requirements.
Key applications include:
- Internal locations in all corrosivity zones for steel not in contact with masonry.
- Internal locations not subject to wetting for steel in contact with masonry.
Our updated system is cost-effective, operationally seamless, and delivers exceptional performance without adding to project lead times.
What Are the Cost Implications?
The new compliant paint system comes with a price increase of 6% to 7% per metre for beams and columns. However, the long-term benefits of enhanced corrosion protection outweigh the upfront costs, offering significant savings on maintenance and repairs over the life of your project.
Preparing for the Transition
Starting January 1, 2025, the older zinc phosphate primer will no longer be offered. Instead, our new compliant coating will become standard, identifiable by its dark grey colour with the SB gold stamp of compliance.