Ross Patrick Robinson

Neighborhood apartments, commercial buildings and even some downtown office structures have glazed terra-cotta—one of the most prominent features of turn-of-the-century Chicago architecture. Passing by the Wrigley Building on Michigan Avenue, the Reliance Building on State Street or those white corner-lot buildings at the intersection of Lincoln, Halsted and Fullerton in Lincoln Park, you’ve probably wondered about their luster. Their facades are largely intact, even after 100 years. While wildly different in scale, each building is striking in its architectural sumptuousness. They're part of what makes Chicago one of the best cities for architecture, with details that are rarely executed today, including terra-cotta exteriors.  In the latter half of the 19th century, catastrophic fires in many American cities coincided with technological developments to propel the once niche use of baked earth into mainstream urban design. After the Great Chicago Fire in 1871, it was found that many cast iron structural supports failed in the brutal heat of fire, while stone and brick components often cracked. In response, engineers made a concerted effort to develop more fire-resistant materials to protect structural components and maintain the façade's integrity. In the search for something stronger, terra-cotta turned out to be flame resistant and adequately protect structural metal beams and other vulnerable areas. With high-rise architecture, skyscrapers and steel-framed buildings came