FEATURE: RESILIENT BUILDING DESIGN AND CONSTRUCTION BUILDINGS ACCOUNT FOR AROUND 40 PER CENT OF ENERGY RELATED GLOBAL CARBON EMISSIONS. WITH OVER 42.2 BILLION TONNES OF MATERIALS CONSUMED ANNUALLY, IT IS LITTLE SURPRISE THAT BUILDINGS ARE RESPONSIBLE FOR AROUND 50 PER CENT OF GLOBAL MATERIAL USE. And the demand for building materials is only growing. For instance, average world steel use per capita has steadily increased from 150kg in 2001 to 224.5kg in 2018. By 2050, worldsteel predicts that steel production will grow by 30 per cent to help meet the needs of the world’s growing populations.
Producing steel is energy intensive. However, once produced, steel is 100 per cent recyclable, and can be infinitely recycled without any loss of quality. With a global recovery rate of more than 70 per cent, steel is the most recycled material on the planet. Being magnetic, steel is easy and affordable to recover from almost any waste stream. Steel has a number of green virtues for construction too. The decision to use steel has benefits right from the initial stages of a project. Its great strength to weight ratio produces a lighter structure that minimises foundation work and the excavation and earthworks involved.
With a rising need to address climate change and raw material depletion, there is growing demand for both sustainable and resilient building design and construction. Industry and consumers alike are placing a greater emphasis on building materials that are easily recyclable and re-usable, and that perform not only for the lifecycle of a building, but beyond.
As building proceeds, steel can be fabricated offsite in a factory and delivered to site as required. This means that the components can be fabricated with great accuracy and be assembled onsite with minimum labour and truck movements. Moreover there is virtually no waste to be disposed of, solving a major logistic and environmental problem on most construction sites.
This type of approach encompasses the use of lighter and high-performance materials that are easier to install and maximise internal spaces—materials like steel.
Using steel in the design of a building allows larger column-free areas to be created, making better use of natural light to save energy. As buildings age they often have to undergo radical
modification to meet changing circumstances and in this event a steel structure is much easier and quicker to modify and get back in use, using much less energy and creating much less waste as any redundant steel has immediate scrap value for recycling. Ongoing research is producing new steels that are even stronger and lighter than those available today. These new steels offer myriad benefits. With their higher strength-to-weight ratio, the newer steels can be used to manufacture tower sections of up to 30m. This reduces emissions during transport and assembly. Higher grade steels are also being developed for construction. They enable the construction of larger and taller buildings in a more efficient way and produce the lowest possible amount of waste. The use of higher grade steels is expected to reduce the quantity of steel used in construction. Transportation costs are reduced thanks to the thinner, and therefore lighter, steel components. They shorten the time needed for processing at plants and on-site construction, largely due to a reduction in the number of welds required.