Concrete literally surrounds our lives. With an estimated 10 billion tons of concrete produced each year, it has become the single most widely used material in the world. It is also one of the most consumed substances in the world, only losing out to water. More than two thirds of all people on this planet live in a concrete structure. Of course, with this, it also means that traditional concrete is becoming one of the most active contributors to greenhouse emissions and global climate change. It’s not so much because we have so much concrete, but more because we produce such a staggering amount of it.
Concrete is essentially a mixture of cement, air, water, sand, and gravel. The production of cement in particular contributes to around 8% of the world’s carbon dioxide emissions. Similarly, water, sand and stone need to be sourced from large areas of natural resources. This takes up even more energy, especially when you consider that concrete production makes up around 20% of the world’s industrial water consumption. With growing populations around the world, we will begin to see an even larger increase in cement production and, therefore, carbon emissions.
So what can be done about the rise in carbon emissions due to the adverse effects of concrete production? It’s been suggested that total emissions created by concrete production need to be reduced by at least 16% by 2030 before we risk irreversible damage due to climate change. Though long term concrete/cement replacement solutions are already being considered, some architects and developers are already experimenting with carbon neutral, eco-friendly alternatives.
Sustainable & Environmentally Friendly Alternatives To Traditional Concrete
In this blog, we explore 5 alternatives to concrete which will have less of an impact on climate change and help us achieve carbon neutrality.
AshCrete
AshCrete is composed of at least 97% recycled materials and is created from what is know as Fly Ash, which is a byproduct from burning coal dust. Much of the Fly Ash we produce end up in landfills where itself has it’s own negative environmental impact. However, there is a way to combine fly ash into concrete through molecular engineering, which creates AshCrete. This type of concrete does not use the traditional burning or cement production methods during production. It also needs less water than traditional concrete, which overall is much more eco-friendly. It’s even suggested to be superior to traditional concrete in a number of ways including reduced bleeding, reduced shrinking, has a stronger resistance to chemical reactions (such as alkali-silica reactivity) and the end result is a much stronger and tougher concrete overall. Though AshCrete has shown so much promise as an alternative to traditional concrete, there are some drawbacks. The biggest problem is whether there maybe any adverse health benefits from living in a structure made from this material, due to the fact that AshCrete derives from coal. It also may take considerably longer for AshCrete to reach it’s full strength than traditional concrete after being poured and it’s problematic to use this material during cold months. Overall, a lot more research is needed to assess whether it really is a viable replacement.
Ferrock
Ferrock is a relatively new concrete solution but it has shown to be very promising. Essentially, Ferrock uses a mixture of Iron Powder, Fly Ash, Lime Powder, Metakaolin and Oxalic Acid. It’s similar to AshCrete in the sense that it’s produced from recycled materials including steel dust from the steel industry and silica from ground up glass. Iron that is within the steel dust reacts with CO2 to form iron carbonate. This results in a particularly durable building material which is stronger than traditional concrete – up to five time stronger to be precise. Further, it has been suggested that Ferrock is strong yet very flexible which makes it potentially suitable for towns and cities that deal with a lot of seismic activity. It’s also excellent in marine environments, because the unique properties of Ferrock actually make the building material stronger when around salt water. Most importantly however, Ferrock has been show to absorb and trap carbon during the drying and hardening process, which means it’s both carbon neutral and even carbon negative. Despite of the many benefits, it has been suggested that large scale development use may be extremely expensive and that it might be better suited for small scale projects. Only time will tell if Ferrock is a good substation for concrete.
Micro Silica Concrete
Micro Silica, or “Silica Fumes”, is an extremely fine powder which is the by-product of ferrosilicon alloy and silicon production in high-temperature electric arc furnaces, particularly when silicon dioxide condensates. When mixed with concrete, this super fine substance can increase the durability and strength of traditional concrete. This is due to two reasons. First, Micro Silica itself provides a much more even distribution and larger volume of hydration. Secondly, when mixed with concrete, Micro Silica can decrease the average size of pores in the cement. Overall, it can displace anything from 7% – 12% cement in concrete due to it’s unique properties. The result is a product with lot more compressive strength while being considerably less porous. It fares much better against harsh chemicals compared to traditional concrete and even reduces the rate of carbonation, which makes it a more eco friendly alternative too. The downside of Micro Silica is that it’s difficult to handle due to the extreme fineness of the powder.
Mass Timber
Unlike some of the other alternatives in this article, Mass Timber Construction can completely replace concrete altogether. Mass Timber, or Massive Timber, embodies a number of products such as laminated veneer lumber (LVL), nail-laminated timber (NLT), glue-laminated or glulam beams, and dowel-laminated timber (DLT). However the most popular and sought-after Mass Timber is cross-laminated timber (CLT). CLT is made from layers of solid timber planks which are trimmed, kiln-dried and then glued together in alternating directions to make stable solid wood panels that can be used in construction. This construction material can be large – up to 30 centimetres thick, over 5 metres long and nearly 30 metres wide. It’s strong, durable, and can easily match or even succeed traditional concrete. Contrary to what you may believe, it’s actually none flammable and bares well against heat and fire compared to structures made of steal. It also reduces carbon emissions substantially, can make construction projects faster and cheaper, holds up well against earthquakes (in experiments), and can help create new jobs. CLT has already been used to create the worlds largest timber based tower in Norway with plans for an even bigger wooden skyscraper in Chicago. Despite being such a promising replacement for concrete, there have been some set backs to Mass Timber – particularly with how a sudden demand for wood will have an impact on forestry. Experts believe that the use of Mass Timber must be coupled with sustainable forestry, otherwise all the good that Mass Timber offers can easily be undone.
Mycelium
Mycelium may seem like an odd substitute for concrete, but the truth is that there has already been a considerable amount of research into its constructive potential. Simply put, Fungal Mycelium is comprised of the root structure of fungi and mushrooms, which in turn is used to create a sustainable building material such as Mycelium Bricks. The threads of Mycelium, known as Hyphae, is extremely strong and can be grown in such away that it creates a durable brick. These bricks can then be used in a number of construction applications including structures, buildings, and more. The upside of Mycelium as a construction material is that it’s 100% organic, biodegradable, and completely carbon neutral. It also has shown to trap more heat than fibre glass, is fire proof, non toxic, and low cost to produce. Though it’s suggested not to be as strong as traditional bricks (unless comparing pound-to-pound), this is compensated by the fact that it’s a much lighter construction material. Due to which, relatively large structures are still possible as was shown in 2014 with the completion of “Hy-Fi” at MoMA which stood over 12 metres high. Despite it’s many advantages, one of the big disadvantages is that Mycelium Bricks tend to become less water resistant over time and is not suitable for humid environments. This limits where Mycelium construction projects can be built. Also, because of the lightness of the material, it can only really be used for non-load-bearing structures.
Conclusion
Though there some exciting new developments when it comes to sustainable and eco-friendly concrete alternatives, there are also some challenges that come with it. This article only explored a small fraction of the different substitutes to traditional concrete. There are many new projects exploring a range of alternatives which are already underway. It’s exciting to see what the future will bring as we continue to combat climate change and carbon emissions.
Environmental and Social Governance
If you would like to learn more about Knightsbridge Development Coporation’s commitment to Environmental and Social Governance, then be sure to check out our web page on the matter. If you would like to get in-touch with one our offices on some consultation on a development project, then you contact us right here: https://knightsbridgecorp.ca/contacts/