Adopt an Artifact: Northwestern Terra Cotta Collection

The National Building Museum’s Northwestern Terra Cotta collection is one of the largest and most sophisticated of its kind in the United States, comprised of more than 64,000 architectural drawings of decorative terra cotta used on over 13,000 buildings constructed nationwide between 1900 and 1956. August 2025 marks the 100^th anniversary of one of the Northwestern Terra Cotta Company’s (NTCC) (1877-1956) most enduring contributions to the American built environment: the prototypical public schoolhouse, first implemented in Chicago and later adopted as a model for public educational spaces nationwide. 

Architectural terra cotta gained prominence following the devastating Great Chicago Fire of 1871, which underscored the need for industrial-scale fireproofing in American urban centers. By the early 20^th century, terra cotta was firmly established as America’s premier material for detailing commercial and civic structures, defining the new, steel-framed skyscrapers in Chicago and New York City until the rise of modernist glass curtain walls in the 1950s. 

At the material’s peak popularity, the NTCC pioneered terra cotta manufacturing. By 1920, its Clybourne Avenue plant in Chicago covered 24 acres, making it the largest facility of its kind in the world. The company recruited European craftsmen to bring expert artistry to its model shop where skilled draftsmen then translated architectural blueprints into detailed “shop drawings.” These drawings identified exactly where and how each puzzle-like piece would be secured to its supporting structure. 

NTCC worked on over 15,000 building projects throughout the company’s lifetime. Its portfolio included works by international architectural luminaries like Louis Sullivan, Daniel Burnham, Albert Kahn, and Frank Lloyd Wright. NTCC also contributed to the distinctive Wrigley Building, the first skyscraper completely clad “from sidewalk to searchlight” in terra cotta, and left its mark on countless public-facing projects, from the Chicago Theatre and Opera House to school buildings across the country.  

Edward Mertes, a Chicago-based terra cotta restorer, acquired this collection of NTCC’s records after it shut down in 1965. He donated 64,000 drawings to the Museum in 1983. The collection was the first significant donation to the newly formed Museum and cemented its reputation as the nation’s repository for architectural heritage. 

Help us preserve this history!  

The NTCC is not only significant nationally, but also remains essential to currently practicing restoration experts working to save historic buildings. Approximately 70% of the research requests the Museum receives about the collection are from companies that restore and replace architectural terra cotta. Original “shop drawings” are essential to safely and accurately repair complex terra cotta tile arrangements. The remaining research requests come from historic preservation advocates working to save a building from demolition.  

Through the Museum’s Adopt an Artifact program, you can play a direct role in safeguarding historic structures. Your support helps conserve rare and delicate objects, ensuring they’re preserved for future exhibitions, research, and generations of curious builders.  

Click here to Adopt an Artifact and help protect this legacy. 

The National Building Museum is home to the nation’s foremost archive of American architectural and design heritage. The Adopt an Artifact program allows you to directly support the proper care and preservation of objects with critical conservation needs, helping the Museum continue its mission to inspire curiosity about the world we design and build. To support this initiative, click here.