Twenty times stronger than wood, highly recyclable, and fire-resistant. When it comes to metals, steel really is in a class of its own. It’s prized as a construction material for its high tensile strength and relatively low cost, making it enormously popular in the industry. In fact, construction is responsible for over 50% of the entire world’s demand for steel, which is commonly found in buildings’ structural components, exteriors, and even on their roofs.
One thing that sets steel apart from other metals is that its unique properties allow it to be recycled again and again without diminishing quality or performance. This helped the overall recycling rate of steel reach 86% in 2014, and it’s why two out of three tons of new steel are made from old steel.
More than 82 million tons of steel were recycled in the U.S. in 2008 alone, more than aluminum, glass, and paper combined, according to the Steel Framing Alliance. Using certain lighter varieties of steel in building construction even allows companies to use less heavy machinery on site, so it is even more eco-friendly.
Earth-Friendly Light-Gauge Steel
Conventional steel is already pretty eco-friendly compared to common building materials like brick and concrete. However, there are types of steel out there that are even greener. Light gauge steel, sometimes called cold-formed steel, is made by forming sheets of the material into various shapes, either with a press or by roll-forming. Unlike conventional structural supports, there is no heat required, cutting down on emissions. As a result, cold-formed steel is less expensive and faster to produce.
“Light-gauge steel framing is a modern and efficient construction technology which is getting popular all over the world. In addition to offering strength to the overall structure, it also allows greater design flexibility at lesser costs,” said IZA Canada Technical Expert Kenneth D’Souza at a recent webinar discussing sustainable construction technologies.
“In addition to offering strength to the overall structure, it also allows greater design flexibility at lesser costs.”
Light-gauge steel construction has become popular in Europe, India, and New Zealand, where wood framing beams have been replaced with thin galvanized steel. The method requires minimal usage of heavy equipment, less water and sand as compared to conventional structures, the panelists noted.
Steel’s Journey Toward Sustainability
Steel production has gotten considerably greener over the decades, not just in deference to the environment, but also because using less energy and recycling usually saves money. Over the last three decades, steelmakers have reduced the amount of energy necessary to produce steel by one-third, and nearly all water used in its production (95%) is cleaned and reused. According to the American Institute of Steel Construction (AISC), by weight, 81% of all steel products can be recovered for recycling at the end of the product’s lifecycle.
Steel’s strength also means builders need less of it than they would weaker materials, allowing for more usable open spaces in completed structures. The U.S. Green Building Council’s LEED rating system gives maximum credits for structural steel because of its high proportion of recycled content and its high rate of recycling. U.S.-produced steel typically contains around 93% recycled scrap steel, and AISC singles out the steel industry as going above and beyond regulatory requirements when it comes to energy efficiency and emissions.
Steel’s flexibility as a material also makes it a boon for prefabrication. Steel can be fabricated to exact specifications off-site and transported to be quickly assembled at the jo site, allowing for fewer workers on-site and reduced emissions from construction vehicles. Its durability also means it needs significantly less ongoing maintenance than other materials, saving firms time and money while helping curb emissions even further.
Steel is everywhere we look. It’s used to make everything from buildings to infrastructure, to machines, trains, cars, and boats. Its reputation as one of the world’s most popular building materials is well-deserved considering its strength and durability alone. The fact that it’s also one of the most sustainably-produced and most highly recycled building materials is an added boon, making it even more desirable as the construction industry seeks new ways to be better stewards of the environment.