Aircrete Vs Concrete - uceed-nid-nata-GK

Our modern world is built out of concrete. Every major city is filled with this material and most new buildings are based out of its physical and morphological properties. 

With such presence in our industry and day-to-day lives, one might assume that concrete is the most effective and versatile material we have, and that’s why we’d use it so much. 

The reality, however, is different. While, indeed, its versatility is pivotal to our cities’ continuous growth, its effects are also very dangerous to society, especially the environmental damage of the concrete production and industry.

The impacts of producing concrete and one of its main components, cement, are countless. The cement industry, for example, is one the world’s leading carbon dioxide generators, which is a potent greenhouse gas. It has many other damaging effects which are widespread in the news today with the growth of green consciousness.

And not to play devil’s advocate, but  let’s make it clear: some components of making concrete are actually good for the environment, since it uses many materials that would otherwise be filling landfills or polluting riverbeds and forests. Also, there have been active efforts in order to increase the smart use of said materials.

Although that’s important, concrete production’s gas emissions and extremely high water usage- which is often overlooked- undoubtedly make it a mediocre material choice when it comes to green building, clearly overcoming its ‘good deeds’ to nature.

So, how can we replace this material that’s so important to the building industry? Replacing, actually, may not be the answer, if not for adapting. In this case, Aircrete has become an interesting alternative material whose use has been growing recently. It is a building source that uses the traditional concrete mixture and incorporates either foam, expansive agents, compressed air or aluminum powder with other non-toxic elements which, due to their chemical nature, expand and create bubbles inside the concrete block, making it more lightweight and easier to transport and build. This means that there are many ways to make Aircrete, and some of them can even be done by normal people with normal equipments at home. So, the term Aircrete is actually very broad, normally referring simply to concrete with air inside rather than one specific way to do it.

 

And maybe you’re asking yourself if having air inside your brick-walls is really a good idea, but the structure, proportion and composition of Aircrete develops on the benefits of all of its components. The air inside helps with thermal and acoustic insulation, also making it easier and softer to carve and work than normal concrete.

The cement in it, as in its ‘rival’, provides for high compressive and low tensile strength, meaning it can be a replacement for old concrete without having to make structural changes in renovations, for example. It also doesn’t require specialised labor, since the physical properties of both materials are similar, amounting for a reasonable substitution plan to move on from old concrete to new Aircrete buildings.

Besides Aircrete’s interesting composition, it’s also a very rich building material from the all-round consumer perspective. As concrete, it’s fireproof, weather and water resistant; it isn’t organic as wood, so it doesn’t decay easily nor does it attract pests. But more than that, it has one characteristic every consumer loves: Aircrete is a fairly cheaper option to build.

 

Construction is as simple as with normal concrete, so labor won’t be expensive, it is extremely low maintenance, doesn’t require aggregates and it has any type of insulation one may need included in its structural function (the block can thicker or thinner to suit the climates needs). That means that using Aircrete is not only easier, but requires fewer side materials which occupy a lot of space, time, transportation and money.

And it’s benefits are even bigger when the environmental aspect comes into play. We’ve seen already that normal concrete can lead to a lot of greenhouse gases and water usage when being fabricated, and in this department Aircrete also has some advantages. Since its composition is more mixed and includes less cement, the water, electricity and heat needed to produce it are lower and therefore less costly to nature, also generating less damaging gases. Now, with newer alternatives to the traditional cement which is normally used, Aircrete tends to be an even more renowned green  building material by the day.

 

So, why aren’t we seeing Aircrete everywhere instead of concrete? The reality is that we are so immersed in using normal concrete that its influence and industry are extremely strong.

In most countries, Aircrete is still completely unknown and concrete is the be-all and end-all material in construction. How to change that? Through brave architects who push it into use, just like those who in the twentieth century praised concrete until our cities were covered in it.

 

Autoclaved aerated concrete (AAC, Aircrete)

Autoclaved aerated concrete is a versatile lightweight construction material and usually used as blocks. Compared with normal (ie: “dense” concrete) aircrete has a low density and excellent insulation properties.

 

The low density is achieved by the formation of air voids to produce a cellular structure. These voids are typically 1mm-5mm across and give the material its characteristic appearance. Blocks typically have strengths ranging from 3-9 Nmm-2 (when tested in accordance with BS EN 771-1:2000). Densities range from about 460 to 750 kg m-3; for comparison, medium density concrete blocks have a typical density range of 1350-1500 kg m-3 and dense concrete blocks a range of 2300-2500 kg m-3.