Concrete Cancer Repairs

What is Concrete Cancer?

Concrete cancer is the result of the steel reinforcement within a concrete slab rusting.  As the steel rusts it expands and displaces the concrete around it which causes it to become brittle and crack; effectively destroying the concrete from the inside out, thus jeopardising the integrity of the structure.  The term “cancer” is used because of the nature of the corrosion – the cracks allow further exposure of the steel to environmental contaminants, which in turn speeds up the corrosion process.

How to Treat Concrete Cancer?

There are three most common types of treatment for concrete cancer.  If the problem is related to concrete carbonation and low concrete cover, the solution involves implementing a polymer modified repair system. This includes repairs to all spalled areas by removing the concrete behind the steel reinforcement, removing the rust and following with an application of a steel primer and polymer modified materials. Then finish the process with an anti-carbonation protective coating. If the problem source is associated with chloride contamination of the concrete, the repair process is more complex and usually involves speciality concrete repair solutions such as cathodic protection. If the concrete cancer is less severe, then you could use the simple replacement method of removing the damaged concrete, cleaning and/or replacing the exposed steel that’s rusted and then filling the cracks.  

Concrete cancer treatment should only be completed by professionals.  Applying an incorrect repair method, or using the wrong materials, could become a costly mistake – the unsuitable treatment will conceal and the unsuitable treatment will only conceal the damage and delay the foreseeable repair.


    Did you know that currently concrete repairs are unregulated in WA? How do you know who to trust? Read more...

    What causes Concrete Cancer?

    Concrete cancer is caused by carbonation, moisture, efflorescence and salt.  This can occur due to a number of reasons such as:

    Badly Poured Substrate

    Badly poured concrete allows moisture to penetrate into the cracks and voids, interact with the steel reinforcement and initiate concrete cancer.

    Poorly prepared steel reinforcement

    Poorly prepared steel reinforcement when the original concrete was poured leaves the slab vulnerable to concrete cancer.

    Failed waterproofing

    Concrete structures that have not been waterproofed sufficiently due to cost-cutting or general degradation allow for water ingress which results in concrete cancer.

    Incompatible metals

    Incompatible metals in close proximity to each other cause a chemical reaction which permits water to penetrate the slab, access the steel reinforcement and initiate the concrete cancer process.

    Structural cracks

    Structural cracks in concrete retaining walls, columns, beams and slabs commonly attributed to defective design, workmanship or materials, allow water to enter the structure and concrete cancer to form.

    Stress fractures

    Stress fractures caused from weight bearing or general wear and tear lets water infiltrate the concrete and react with the steel which leads to concrete cancer.

    Low quality materials

    The use of poor-quality materials during the initial stages of forming reinforced concrete may result in inadequate cover around the reinforcement, allowing the corrosion process to commence, which in turn leads to concrete cracking and concrete cancer.

    Poor steel placement

    When the ends of the steel reinforcement are placed too close to the surface of the concrete, water is able to seep through and trigger oxidisation of the steel’s lime and other chemicals, triggering concrete cancer.

    Failed repairs

    Unrealistic and low quotations lead to failed repairs as it may encourage contractors to carry out only partial repairs, use less steel reinforcement in the concrete or use low quality materials.

    How to repair concrete cancer?

    Concrete cancer repair is not a DIY job and there is no “one size fits all” solution.  The concrete spalling repairs should be completed by an experienced professional who can determine the best repair solution based upon the building materials and the extent of the damage.  


    Is concrete spalling dangerous?

    Concrete cancer on a structure not only looks unappealing, it can be very dangerous. If the structure is in an area that is accessed by people, the spalled concrete can be dangerous in terms of falling debris or trip hazards – potentially injuring or killing a person and/or causing damage to property (i.e. vehicles); putting building owners at risk of a negligence lawsuit. Left unchecked and with increased exposure to the elements, concrete spalling will accelerate and spread resulting in larger and more costly repair costs and/or an unstable structure.

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    Professional repairs can have a disproportionate impact on asset value and therefore it’s important to select a capable contractor to complete the repairs.  Drawing on our experience and industry best practice, BUSS’ team have been servicing our clients in the commercial, industrial, residential, mining and resources market for more than 20 years.  Our specialist remedial team have been applying their expertise in completing condition assessments, creating action plans to remediate issues, developing repair methodologies, providing product recommendations and undertaking repairs via trusted techniques to eradicate underlying problems and renew assets to their desired state.

    Our proven track record in effective remedial solutions and quality workmanship, supported by our affiliation with leading industry organisations – Australian Institute of Waterproofing, the Australasian Concrete Repair Association and the Strata Community Association, along with our Cert III accredited applicators, offer our clients peace of mind for all their concrete repairs.  Our association with these leading organisations allows us the advantage of being one of the most qualified, trusted and reputable remedial contractors in WA.

    BUSS is your ‘go to’ contractor for all your concrete cancer repair needs in Perth and the metro area, as well as Regional WA.  For more information, please feel free to contact us below, or call us on 08 9444 1732.

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