What Is Foam Concrete?

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Foam concrete is a cement material manufactured by mixing a cement paste, also called slurry, or mortar with a manufactured foam material. This makes a substance that is porous and lightweight. The volume of slurry to foam in the mixture dictates the density of the final product and how it will be used.

About Foam Concrete

Foam concrete, also called cellular concrete, is typically made of water, cement and foam. This mixture may also include aggregates or chemicals added to change its physical properties. It is a lightweight material with low density and limited strength in most applications. It is typically a self-levelling and compacting material that is more resistant to cracking and shrinkage than standard concrete mixes.


The strength and durability of foam concrete varies depending on the components mixed into it. For example, foam concrete made with sand is stronger and has a higher density than foam concrete made with just concrete and foam. Some foam concrete mixes include Portland cement that is mixed with the cement and foam by itself or mixed with pulverised fly ash. It may also include limestone. Each of these mixtures makes a cement product ideal for different applications, but typically all foam concrete products become more resistant when compressed and aren't vulnerable to liquefication or settlement once hardened.


Foam concrete is lightweight, so it's ideal in applications where large concrete forms are needed because it is easier to move from one location to another. It is easier to cut than standard concrete, making it ideal in situations where holes for wiring and pipe must be cut into the concrete. Foam concrete contains no toxic substances that might be harmful for the environment, making it an eco-friendly building material as well. Because foam concrete may consist of up to 80 per cent air, it has excellent insulation, sound-absorbing and fire-resistant properties.


Foam concrete made with cement and foam only is typically used in roofs and floors as an insulating material. Its low density makes it unsuitable for structural applications but it may be used to fill hollow blocks and voids between bricks and to fill unused culverts and underground voids such as old pipes. Foam concrete made with sand, cement and foam is denser, making it ideal for applications that require a structurally sound material such as when making precast blocks, for insulation and sound- proofing in residential and commercial buildings, foundations and for concrete slab work. Foam concrete may also be used for filling arches in bridges and viaducts, soil replacement and stabilisation, and for road foundations.