This week's hot item


Concrete Cancer

Print-friendly Version

Concrete Cancer

What is concrete cancer, and how to prevent it

If you have concrete cancer in your home, this may call for a renovation. Preventing concrete cancer when you are building is the best form of cure, to avoid an expensive and unnecessary renovation in the future.

What is concrete cancer? Concrete when used in construction, needs to be reinforced with steel, in the form of bars or mesh. However, when exposed to air or water, steel corrodes, which causes it to expand. The expansion of the steel causes the surrounding concrete to crack, and therefore undermine the strength of the building. The cracking or break down of the concrete is known as spalling. The cancer aspect is due to the progression of the corrosion of the steel spreading through the inside of the concrete. Once the concrete cracks, it further exposes the steel to the atmosphere, and the process continues.

It is straight forward to assume that as long as the steel reinforcements are protected from air and water, they can’t corrode, and therefore concrete cancer can be avoided. The porous property of concrete is something which can be affected by the quality of the constituent ingredients in the concrete materials, such as the aggregate. Another cause is the presence of chlorides in salt water can enter the concrete after it is built, and cause corrosion. This is an issue with buildings near the ocean, such as beach apartment blocks.

Other factors causing the exposure of steel to the elements include building defects, for example the concrete not being set properly, or not effectively covering the steel. Environmental factors such as the movement of earth under the building can cause the concrete to crack, thereby exposing it to the elements, or water soaking up from underground. Weathering and erosion of concrete, as well as exposure to chemicals such as acid or even bacteria can undermine concrete. Temperature and climate are also factors which can cause concrete to break down, as water can freeze and thaw on its surface.

What is the solution to preventing concrete cancer? Changing material of the internal reinforcements is one option, and bamboo has been proposed as an alternative in some places in the world. Although its strength may be similar to steel, the concrete has difficulty binding to the bamboo. Coating the concrete in paint is another option, especially if the paint contains chemicals which are resistant to chloride.

If you experience concrete cancer, it can be fixed, however it is important for the problems to be correctly diagnosed by a professional.

Return to External Work

Auction (New)

Bid Go

Sell Go

Buy Now! Visit the Auction Page to bid on renovation products and building materials online. Check out our auction site and start your home renovation today!