Concrete Spalling.
Spalling is usually caused by moisture penetrating the concrete and reaching the steel reinforcement. When the steel corrodes, it expands, creating internal pressure that forces the surrounding concrete to crack and break off. Common contributors include:
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Water ingress and poor waterproofing
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Carbonation (CO₂ reducing concrete alkalinity)
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Chloride exposure (coastal or de-icing salts)
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Poor-quality or under-designed concrete cover
Why it’s a problem
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Reduces structural capacity and durability
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Allows ongoing corrosion to accelerate
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Creates safety hazards from falling concrete
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Can lead to costly structural failure if left untreated
How it works
1
Remove Loose Concrete
The repair begins with removal of all loose, delaminated, and contaminated concrete back to sound substrate, ensuring that hidden defects are fully exposed.
2
Treat Reinforcement
Any corroded reinforcement is then cleaned, treated, or replaced, and protected with corrosion inhibitors or protective coatings to prevent further steel deterioration.
3
Reinstate Surface
Once the reinforcement is stabilised, the affected areas are reinstated using engineered repair mortars or concrete systems designed to match the original structural and durability requirements.
4
Finish
The repair is then finished with protective coatings or waterproofing systems, where required, to limit future moisture and contaminant ingress.
This approach restores structural capacity, extends service life, and improves long-term durability, preventing the recurrence of spalling and ensuring the ongoing safety and performance of the structure.
