Dr. Olivier Vassart, Chief Executive Officer Steligence at ArcelorMittal, and a constructsteel Vice-Chair.

As part of a series of Q&As, constructsteel is interviewing experts within the construction sector on aspects of steel’s performance and sustainability in the built environment.

In 2015, the Paris agreement was a turning point to tackle climate change. It set ambitious targets to substantially reduce global greenhouse gas emissions and limit the global temperature increase in this century. This agreement set the tone and since then countries and even industries have started to do their homework. In the construction business, steel has been used for centuries, it will remain a key material and has great credentials in terms of sustainability.

Steel is by nature a sustainable material. There is no need to recall the simple fact about the total recyclability of steel without any loss of its properties, and this indefinitely. This makes it the perfect material to respond to the new circularity criteria for our construction projects. But the sustainability benefits of steel do not stop here. There are plenty of other advantages of steel as an important player in the circular economy that should be talked about more. Let’s take a quick look at three of them.

First, a simple way to reduce the impact of steel is by using less quantity but better quality material. Designing a building can be improved with a good knowledge of the specifications of the material and the different options there are on offer.  High strength steel is a good example. Using S460 or Grade 70 and above, instead of S235, S355 or Grade 60 can drastically reduce the weight of the steel needed to achieve the same result. And there is nothing better for the environment than material that is not used. A key point in this matter is the interaction between the engineering offices and the steel producer. We have a key role to play in helping them think about their projects and share our knowledge.

The second option to reduce the impact of a building is to look at the design itself and to propose options that will make it more flexible during its lifespan without an additional cost that must be paid today. Long spans with steel can meet this requirement and can make building more “reusable”, increasing their lifespan. After their first use, the steel can be easily refurbished and won’t need to be destroyed. This could be called a holistic approach to the full life cycle of the building, keeping in mind the future use of the building without compromising further options. In addition to this, with the rise of digitalisation and BIM objects, a building can be designed with the aim of easily dismantling it and to have pieces that will be re-usable after minimum refurbishment.

Third, steel companies have clear strategies to decarbonise their production to meet the 2030 and 2050 objectives. Today’s innovations already allow some producers to put steel products on the market with a carbon footprint that is significantly lower than average steel products. Combining these possibilities with the use of the high strength steel mentioned before, means that solutions exist for construction that uses steel with an embodied carbon which meets today’s strongest environmental requirements.

When looking at the trends in today’s regulation, for example in Europe, the increase of greener requirements in the construction market is a positive sign and will support the developments of a better use of the material (less material, more re-use, refurbishment and recycling) but also in the development of more sustainable steel. At ArcelorMittal, we already have the product portfolio today that can help real estate owners to deliver low carbon buildings, and we can also provide the necessary expertise and support to architects and designers to create high value built assets with the lowest carbon footprint.