Any conscientious property manager or real estate investor must know the risk of concrete cancer in buildings. As the name suggests, concrete cancer is something you want to avoid.
Therefore, anyone involved in real estate needs to know how to identify concrete cancer and understand the common causes of concrete cancer. Understanding concrete cancer can be integral to protecting your investment in a property and the safety of any occupants.
We’ll go through a thorough explanation in this article and also share how to fix concrete cancer.
What is concrete cancer?
The name cancer is apt since concrete cancer is a neglected disease within a building that spreads. Just like cancer in humans, identifying concrete cancer early can be crucial to avoid the worst-case scenarios.
The concrete slabs that make up concrete buildings depend on steel reinforcement, as steel bars help support the concrete. Concrete cancer happens when the reinforcing steel within the concrete starts to erode.
Concrete is a porous material, meaning the concrete surface easily absorbs moisture. When the air and water mix in the concrete, a weak carbonic acid forms that can corrode the steel.
Depending on the concrete grade and the concrete cover level between the concrete and steel, this water permeates the internal wall and causes water damage to the steel reinforcing bar. The steel rusts, putting the building’s structural integrity at risk.
Salt in the air worsens the effect, speeding up the corrosion, and Australian homes near the ocean are at greater risk.
Concrete cancer can lead to building collapse when left untreated. So, you must conduct regular property inspections to look for building defects and potentially perform preventative maintenance.
What are some of the common signs?
Building inspectors can look for many telltale signs of concrete cancer as steel rust. The steel expands as it rusts. As the steel expands, the concrete can break, causing some pieces to fall away.
The process is called concrete spalling. This spalled concrete indicates the broader problem that requires building repair. Yet, before this clear indication of concrete cancer, regular building inspections can help spot other signs:
- Rust stains on concrete.
- Bubbling in the concrete render.
- Leakages from concrete ceilings.
So, before buildings get to the point where there is severe cracking and breakages of the concrete, there are ways to spot damaged concrete and undertake concrete repairs. To best understand concrete cancer repair, let’s take a closer look at those concrete cancer causes.
What causes it?
We have already mentioned that concrete cancer isn’t an issue with concrete but results from the corroding steel that reinforces concrete instead. Therefore, what causes concrete cancer is anything that facilitates the reaction of air, water, and carbonic acid with steel.
Let’s run through a few of the most common concrete cancer causes:
- Stress fractures in the concrete from bearing too much weight or general wear and tear, allowing water to seep through.
- In the past, poor building practices used incompatible metal fabrication that caused a chemical reaction corrosive to the concrete and steel. This building choice was a significant problem when developers started using concrete in Australia in the 50s and 60s.
- Concrete spalling due to concrete cancer leads to further exposure to the elements, creating a vicious cycle.
- Poor waterproofing of concrete.
- Poor design (flattop roofs susceptible to leaks).
- The movement of the earth underneath causes the concrete to crack.
- Poor quality concrete.
- Salt chlorides significantly affect homes near the sea.
How to repair it?
The key to concrete cancer treatment is preventing steel corrosion. It’s also essential to spot the signs early. The earlier you catch and treat it, the more likely you can avoid paying more for repairs than you have to.
Suppose you think you can spot some of the telltale signs of concrete cancer. In that case, it’s best to work with a structural engineer who will perform a thorough diagnostic analysis of the state of the residential or commercial building.
A qualified engineer can identify the leading cause of concrete cancer in your building and help determine what action to take. Here are a few potential solutions, depending on your issue:
1. Polymer-modified repair system solution
This solution is for the issues of concrete carbonation and low concrete cover. This solution entails removing the concrete around the steel and cleaning the steel before applying a steel primer and a polymer-modified material to protect the steel. They may also add ant-carbonation protective coatings to the whole surface of the concrete.
2. Electrochemical treatment solution
This option treats the case of homes near the ocean that are significantly affected by chlorides. These cases need specialist repair work, sometimes involving electrochemical treatment.
3. Replacement
If you are fortunate and catch concrete cancer early, you may be able to replace some broken concrete and rusted steel and simply fill in any cracks.
4. Preventive concrete cancer treatment
If you fix the issue and remove concrete cancer, you must undertake preventive measures to stop the recurring issue. Apply waterproofing solutions to protect the newly repaired concrete and steel.
These preventive measures could include waterproofing products like protection matting or waterproofing membranes over the concrete. Again, a professional can help recommend the best action to prevent any further signs of concrete cancer from returning.
Summing up
Concrete cancer is caused when moisture seeps through concrete and corrodes the reinforcing steel. When this happens, the eroding steel puts the structural integrity of the building at risk.
It’s vital to catch this issue early to avoid costly repairs or building collapse. There are various telltale signs to look out for, including concrete spalling, rust stains, and leakages.
It’s best to get in a professional to diagnose the primary cause of your concrete cancer and to identify the best treatment option. Various waterproofing solutions can help prevent further cases of concrete cancer.
Contact MrPaint today if you need a hand with painting your residential or commercial building. We paint everything from roofs to walls and ceilings.
In 2014 Adrian quit his job and opened a painting business called MrPaint. Adrian is a strong believer in the ‘healthy body, healthy mind’ principle and backs this up by being a competitive track cyclist here in Australia.