Rusting reinforcement, cracked and falling concrete, rust stains on balconies and carpark soffits. We remove the damaged concrete, treat the steel and rebuild the section properly, so it does not come back in five years.
Concrete cancer is the everyday name for spalling caused by corroding steel reinforcement. When moisture and salt, or carbonation over many years, reach the steel inside the concrete, the steel rusts and expands. That expansion cracks the concrete from the inside and eventually pushes pieces off the surface.
It is extremely common in Sydney, particularly in coastal suburbs and in apartment buildings from the 1960s to the 1990s, where cover to the steel is often thin and waterproofing has failed. Balcony slab edges, carpark soffits, columns, beams and window heads are the usual places it shows.
Left alone it only gets worse. Every wet season lets more water reach the steel, the section loses strength, and loose concrete becomes a safety risk for anyone below. Treated properly and early, the repair is smaller, cheaper and lasts.
If any of these sound familiar, it is worth a free site visit. We will tell you straight what your site needs.
Brown streaks running from cracks or the edge of a slab are often the first sign that steel inside is corroding.
Straight cracks that follow the line of the reinforcement, especially at slab edges and beams.
Tapping the surface gives a hollow sound where concrete has delaminated from the steel behind it.
Chunks of concrete dropping from balconies, soffits or columns. This is a safety issue and needs urgent attention.
Visible rusted steel bars where the concrete cover has already spalled away.
Failed waterproofing above a slab is one of the main causes. Water in means concrete cancer is not far behind.
Seeing rust stains or loose concrete? Send us a few photos and we will tell you how urgent it is.
From a single balcony edge to a whole carpark, the method is the same: find every affected area, remove the damaged concrete, treat the steel, rebuild and protect.
The most common location in Sydney apartments. We break out, treat the steel, reinstate the edge and re-waterproof the balcony so it stays dry.
Underside repairs to carpark and basement slabs, beams and columns, with propping and staged work so the carpark can stay in use.
Structural elements over openings where corroded steel has cracked the concrete face or rendered finish.
Grit or mechanical cleaning, corrosion inhibitor and primer, and new bars lapped in where section loss is too great.
Polymer-modified repair mortars for smaller areas, formwork and recasting for larger sections, matched to the engineer's specification.
Anti-carbonation coatings and penetrating sealers to slow future corrosion and extend the life of the whole structure.
A selection of recent concrete cancer repair projects across Sydney.
View all projects
Every concrete cancer job follows the same five steps, from diagnosis to documented handover.
We attend site, inspect the defect and its surroundings, and identify the cause rather than just the symptom. Where needed we take photos, moisture readings and cover measurements.
We coordinate a remedial or structural engineer where required and agree a written scope of works that fixes the cause, not only the visible damage.
You receive a clear, itemised written quote with methodology, materials, access, programme and any approvals. No vague lump sums.
Our crew carries out the work to the engineer's specification and Australian Standards, with progress photos and hold-point inspections at each critical stage.
Final inspection, clean-up and a handover pack: photos, product data, engineer sign-off where applicable, and your statutory warranty under the Home Building Act 1989.
Photos of every break-out, steel treatment records, product data and engineer sign-off where required. Exactly what your strata committee, insurer or buyer will ask for.
Concrete cancer repairs fail when the damaged concrete is not fully removed or the steel is not properly treated. We do the part you cannot see properly, because that is the part that matters.
We diagnose why the defect happened. Patching over the symptom is why so many repairs fail twice.
DBP General Unrestricted (BUP4254812). Qualified for Class 2 apartment remedial work under the Design and Building Practitioners Act 2020.
Builder Licence 384697C, $20M public liability, workers compensation and HBCF cover where required.
We work with remedial and structural engineers from diagnosis to sign-off, so the fix is designed, not guessed.
Photos, product data, hold-point records and certification. Exactly what strata committees, insurers and buyers ask for.
Hands-on remedial and heritage work across Sydney since the 1970s, including jobs other builders turned down.
Real reviews from homeowners, strata and builders.
Constatine and his team did an excellent job repairing and waterproofing our garage ceiling and walls, which had been affected by concrete cancer and sandstone erosion. Constatine is highly experienced in remedial works and provided clear advice, transparent costings, and recommended the best products available to ensure a long-lasting result. We highly recommend METCON for specialist remedial works.
I couldn't be more pleased that I found Constatine and his team to assist our strata building with landscaping, waterproofing, and concrete cancer repairs. He was knowledgeable, reliable, patient, and deeply committed to achieving the best result for everyone involved. I am 100% confident that the work completed will stand the test of time. He will absolutely be my go-to moving forward, and I have no doubt we will work together again.
My partner and I own an original 1920s semi-detached home in Vaucluse, with complex sandstone foundations and multiple structural challenges caused by previous defective works. After years of delays, failed consultants, and no progress, I met Constatine and his team. From the beginning, I was impressed by the detailed review of our plans and the identification of numerous discrepancies that previous builders had missed. The team supported us through lengthy council negotiations, neighbour consultations, and COVID-related delays, even before contracts were signed. Once construction commenced, Constatine and the Meteora Constructions team were exceptional. Progress remained on schedule despite heavy rain, unforeseen structural issues, and highly complex underpinning works that previous builders had refused to undertake. They completed the work efficiently and at significantly less cost than other builders had quoted. I cannot speak highly enough of Constatine and METCON Remedial Services. It is no understatement to say that engaging Constatine and his team saved not only our project, but probably our marriage as well.
Straight answers from the builder. Anything else, just ask.
Remedial building is the repair of defects, damage and deterioration in existing buildings, such as concrete cancer, leaking balconies, failed waterproofing, rising damp and cracked facades. The aim is to fix the underlying cause and restore the building's performance, not just its appearance.
For Class 2 apartment buildings in NSW, remedial work is regulated under the Design and Building Practitioners Act 2020. METCON holds DBP General Unrestricted registration (BUP4254812), so we can carry out that work and lodge the required declarations.
It depends entirely on the defect, its extent, access and the specification. A small concrete cancer patch is very different from a whole-building balcony programme. We inspect for free and provide an itemised written quote so you can see exactly where the money goes.
Residential building work in NSW carries statutory warranties under the Home Building Act 1989: six years for major defects and two years for other defects. We provide full documentation at handover.
Remedial problems rarely come alone. Leaks cause concrete cancer, damp causes render failure. We fix the whole chain.
Back to Remedial BuildingPlain-language guides from our team on the questions we are asked most.
Coastal and harbourside suburbs see the most concrete cancer, but we repair it right across Sydney and surrounding NSW.
A few photos of the cracking or rust staining and the location in the building is enough for us to give you an initial view and book an inspection.
