How green is concrete?
There are a lot of claims about how concrete is or isn’t green. The truth, like in so many other things, is mixed. Here are some things to think about:
Is it chemical free? Concrete can be made from all natural material, or have a lot of chemical additives. Everything in the mix we use is from the earth. The contents are ground and fired white limestone (cement) and mineral sands of different sizes and types. What makes the mix we use unique is the specific choices made of particular kinds, colours, sizes and ratios of these natural materials. Concrete does not off-gas chemical air pollutants. Additionally, the sealers we use are entirely water-based acrylic and, unlike lacquer and some other sealers, safe and easy to ship and to apply.
Where is it from? The main components of concrete are local and abundant. The mix we use is made from all natural materials and does not involve cutting trees or forging new roads. The ingredients of concrete are abundant in supply and easily accessible. Quarries, the primary source of raw materials, can be reclaimed for recreational, residential, or commercial use or restored to their natural state.
What about the cement? The process of creating Portland Cement, the main active ingredient of all concrete, is an energy intensive process, requiring a lot of water and high temperatures, generally in a coal or gas fired furnace. Anyone who calls their concrete ‘green’ without addressing the impact of cement is avoiding this key issue. At Concrete Element, we purchase carbon offsets to help balance this consumption.
And the aggregate… We can use a variety of “post consumer” materials, such as recycled glass. At Concrete Element, we’ve extended the amount of cement used relative to the square feet covered by adding recycled material such as rock, crushed recycled concrete, ceramics, and glass. Only your imagination limits the possibilities.
