Rome wasn’t built in a day, and neither was the Chicago skyline beloved around the world. It took thousands of talented people, millions of work hours, the vision of architects, and the skills of engineers and workers to transform a sketch into the scenic vista we enjoy today. At the heart of this grand project is American steel, providing the literal frame for the city of Chicago that houses thousands of innovative businesses that make this city what it is.  

But the role of steel in building the Chicago skyline we see today wasn’t preordained — it was born in tragedy. The Great Chicago Fire of 1871 leveled the city, precipitating the need for rapid reconstruction of fire-resistant buildings. The steel frames that became the basis of the first skyscrapers provided strength, durability and resistance to fire, as well as an adaptable material that gave architects the scope to both literally and figuratively reach for the sky. The first skyscraper in the world was built here in Chicago in 1885, a half-century before New Yorkers built their own. The Willis Tower, Inland Steel building and other icons of the Loop use steel frames that have defined our city’s skyline for the last century.

Chicago’s past is deeply intertwined with steel, and yet recently, it has become fashionable to push mass timber as a building material for Chicago’s urban development. This would be a mistake. Independent reading of the facts shows the extent to which mass timber’s sustainability is exaggerated by producers and pro-timber architects. For instance, carbon footprint figures commonly cited by the wood industry do not take into account the carbon released by the 64% of a tree’s biomass that is simply left to decay after harvesting; only 36% of that tree actually makes it into a column or beam, according to The Wilderness Society.

Informed design and construction decision-making relies on accurate numbers, and every decision matters — we are leaving both this city and this planet to our children. The steel industry’s significant reductions in carbon emissions have been independently verified and celebrated. Since 1990, the American steel industry has reduced its emissions by 36%, seven times what was prescribed by the Kyoto Protocol, and Illinois’ senators are now at the forefront of granting millions to businesses around Illinois and Chicago for the further development of green technology in steel.

Conversely, steel is an indefinitely recyclable building material which allows for the extension of its life cycle. In fact, the average new steel beam that comes out of an American mill today consists of 93% recycled appliances, cars, and steel from decommissioned buildings and bridges. The steel in a building from the 20th century can be reused in the 21st, 22nd and beyond — over and over again, with no loss of properties. Chicago’s past is the literal foundation of its future.

The refurbishment and revitalization of the Thompson Center mirrors the suggested design for the new Bears stadium. Both projects have similar appearances and use the same construction material — steel, because of its sustainability and strength. Architects who are looking to realize different visions for buildings with different purposes find themselves relying on steel to provide a frame they can depend on. Steel is a versatile material as well as a sustainable one, and this makes it the optimal choice for architects looking to redefine the landscape with striking constructions with lasting aesthetic appeal.

Steel continues to be a versatile building material that can be used in innovative ways by architects to reimagine downtown Chicago. Beyond the aesthetic appeal, steel is more durable, recyclable and sustainable than other building materials — a breadth of strengths that made it the material of choice in the past and the one that should guide us in the future.

Chicago’s skyline of American businesses is iconic, and the landmarks of our city were built with American steel. As we picture the Chicago skyline of the future, steel should remain the sustainable building material of choice.

Brian Raff is vice president of the American Institute of Steel Construction and leads the association's sustainability efforts.

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