Unit 3/1-3 Whyalla Place Prestons NSW 2170
Level 1, 1 Burelli Street, Wollongong NSW 2500
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180 Lonsdale Street, Melbourne VIC 3000
As a leader in end to end waterproofing solutions, including, investigation and remediation – and with exceptional in-house expertise – Danrae Group can recognise and remedy every type of issue.
According to founder and project manager Ron Caruana, one of the most common issues he sees can also be one of the most destructive – concrete cancer.
“I would say we see concrete cancer or concrete spalling in about 50% of cases. Typically, when there is a leaking membrane, there is a significant chance the concrete beneath the membrane will be affected.”
While the impact of concrete cancer is generally very similar – corrosion and loss of structural integrity – there are several causes. Understanding those causes, and having an idea of the treatments, will help you protect your property now and years into the future.
To be clear, concrete cancer and concrete spalling are distinct – if related – issues. They originate when the reinforcing steel framework within concrete is exposed to air or water. With exposure comes corrosion.
Concrete spalling describes the initial stage of the process, when the concrete begins to fall apart. It’s marked by cracking or crumbling, bubbling paint, rust stains and overhead leaks. Untreated concrete spalling will worsen – and without intervention it leads directly to concrete cancer.
There are several potential causes of concrete spalling and concrete cancer. Natural factors that may play a role include saltwater chloride corrosion (for properties near the ocean) and extreme weather, which may prematurely age a waterproofing membrane, leading to leaks.
Sometimes these defects mean the metal reinforcement mesh does not have adequate concrete above it – so there’s insufficient protection from the elements. And poor-quality waterproofing can be the culprit.
“When we walk into a building we tend to look up,” says Ron. “It’s force of habit. If we see a roof with water or rust stains, it often indicates a problem – and that problem may be the first stage of concrete cancer, or it may already be advanced. People generally do tend to leave it until it’s been there for a while.”
Following are some of the most common concrete cancer causes:
One of the most common issues he sees is steel positioned too close to the surface. “The steel has to be a minimum distance from the surface to avoid the likelihood of air or water seeping in. If the property is near water, you need around 50mm. In other areas, it will be 30mm.”
And crucially, anything left untreated or with makeshift repairs will worsen. Choosing to put off waterproofing repairs will in most cases lead to significant building faults. And that means more costly and time consuming repairs later on.
Remedies for concrete cancer vary, dependent on the nature and location of the problem – and how quickly it’s caught. If treated early, it can be a relatively quick process.
Concrete cancer that has spread however, involves a much longer, and costlier, fix.
Repair options include a polymer modified repair system which involves removal of the affected concrete, cleaning of the internal steel and the application of a primer and polymer modified material, then an anti-carbonation protective coating. In severe cases, the steel may need replacement.
A second option is electrochemical treatment, and this is particular to buildings affected by saltwater corrosion.
If the damage from concrete cancer is moderate, the repair will be much smoother.
Concrete cancer is pervasive, so the best approach is to be on the lookout for the tell-tale signs. If you discover leaks, bubbling paint, rust stains or cracks, take action.
Danrae Group has decades of experience and a diverse team trained in every waterproofing technique and every brand. We also provide full diagnostic, solution design and site remediation.
Our end to end process covers every stage from quote to completion. We provide fully certified services, and we always leave a site in pristine condition.
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