Common signs of concrete cancer include cracking, crumbling or peeling of concrete, rust stains or bubbles on concrete or cement plaster, and leaks in the ceiling and walls. Concrete cancer occurs when steel reinforcement inside a concrete slab begins to rust. As steel rusts, it expands and displaces surrounding concrete, causing it to become brittle and crack, exacerbating the problem. It's a good idea to watch for tell-tale signs that your building may be affected by concrete cancer.
One of the first tell-tale signs is the presence of ferrous stains on the surface of the concrete. If the steel rusts inside the concrete, rusty water can bleed the steel to the surface, leaving brown stains on the surface. If corrosion has progressed to the point where steel is expanding, it will usually start to cause concrete to burst or break (known as flaking concrete). There are some telltale signs of concrete cancer, and the most obvious one is the peeling itself.
But already before visible cracks form, crumbling concrete, leaks on internal walls, expanding walls, bubbling concrete plaster and rust stains can tell you what is happening inside the walls. If you suspect that your building has been affected by concrete cancer, make sure that a professional (such as repair builders or waterproofing contractors) review it to know what type of repair work needs to be done. Some common causes of concrete cancer are salt water chlorides, poor waterproofing, construction defects, and concrete that is left without maintenance for a long period of time. Effective Building & Consultancy has more than 20 years of experience in repairing Sydney homes and buildings from concrete cancer.
Our experts conduct an on-site inspection, which provides a comprehensive estimate detailing the best methods for permanently treating and repairing the particular cancer. If the damage from concrete cancer is moderate, you may be able to remove damaged concrete, clean and replace rusty and exposed steel, and fill in cracks. Testing for a particular cancer requires experts, and EBC has the experience and training to identify the particular cancer and repair it. This minimizes the risk of future water damage and prevents harsh chemicals that contaminate concrete from entering through the pores.
Repairing heavily damaged concrete can cost thousands of dollars, so it may not be profitable compared to replacing it. This solution involves removing the concrete around the reinforcing bars and cleaning the steel, before applying both the steel primer and a polymer-modified material. Without repair, particular cancer can cause structural integrity issues making it too big of a repair problem and costing much more if a complete replacement is needed. When it comes to your concrete building or structure, you should constantly maintain it with waterproofing coatings and regularly inspect it for imperfections.
Flat concrete roofs are an example of a building structure that is particularly vulnerable to leakage and water-driven concrete cancer if not adequately waterproofed.