courtesy BTHL

This post is part of a monthly series that explores the historical applications of building materials and systems through resources from the Building Technology Heritage Library (BTHL), an online collection of AEC catalogs, brochures, trade publications, and more. The BTHL is a project of the Association for Preservation Technology, an international building preservation organization. Read more about the archive here.

Although architectural terra cotta is an ancient form of masonry, it is still used extensively today. With a name that literally means “cooked" or "baked earth” in Italian, the durable material is used in pottery, floor tile, and roofing. Beginning in the 1870s, architectural terra cotta found popular use in building exteriors, due in part to the successful white- and cream-glazed terra cotta buildings of the 1893 World’s Columbian Exposition in Chicago. These early buildings created a dramatic contrast to the dark masonry color palette of the Victorian era. In the later decades of the 19th century, however, architectural terra cotta was used much like brick in bearing-wall construction, with individual, unglazed terra cotta elements resembling standard brick colors.

In the early 20th century, architectural terra cotta became an exterior cladding system that could be hung from a steel frame. Manufacturers promoted terra cotta panels, pointing out that they were lighter than carved stone but comparable in durability. The material also had an economic advantage for builders: the repetitive nature of terra cotta's fabrication process made it cheaper than carved stone for elaborate building exteriors. In the mid-20th century, terra cotta evolved stylistically with the Modernism movement into a simple glazed-face building block.

The most prominent use of architectural terra cotta, however, was as a decorative cladding system, particularly for urban commercial buildings. The Flat Iron Building in New York, the Wrigley Building in Chicago, and the Arctic Club Building in Seattle are three terra cotta icons of the early 20th century. Thanks to their durability and ability to mimic large masonry walls, smaller examples of terra cotta building façades can be found in many urban areas across the United States.

Architectural Terra Cotta Work, Part 1, Chicago Terra Cotta Co., Chicago, 1873

Terra cotta door and window caps were a highly decorative lintel that was easily integrated into a masonry wall. This catalog was published during a Chicago building boom just two years after the city's Great Fire in 1871.

Architectural & Decorative Terra Cotta, Baltimore Terra Cotta Co., Baltimore, Ohio, circa 1880

This terra cotta catalog features unglazed panel designs using red or buff bricks, which would have been integrated into masonry bearing wall construction. Inside, 39 beautifully illustrated plates show the details achievable by molded clay.

Architectural & Horticultural Terra Cotta, North Western Terra Cotta Works, Chicago, 1882

The North Western Terra Cotta Co., later Northwestern Terra Cotta Co., was one of the largest U.S. terra cotta companies. Although its original factory complex was located in Terra Cotta, Ill., the company is now headquartered in Crystal Lake, Ill. This early catalog features an array of exterior architectural elements including window hoods, sills, and several pages of elaborate cornice designs.

William Thomas & Co. Patent Steam-Powered Brick, Tile, Pottery and Terra Cotta Works, William Thomas & Co., Wellington, England, 1888

This English catalog features a complete line of fired clay products including brick, terra cotta, roofing, floor tile, and chimney pots. Its extensive illustrations show unglazed and solid terra cotta panel designs for use in masonry bearing wall construction.

New York Architectural Terra Cotta Co., New York Architectural Terra Cotta Co., New York, 1888

This elaborate catalog features unglazed terra cotta units and assemblies for building exteriors and interior fireplaces. The document also contains an interesting history of early terra cotta manufacturing in the U.S.

Conkling-Armstrong Terra Cotta Co., Conkling-Armstrong Terra Cotta Co., Philadelphia, 1898

This catalog doubles as a portfolio of completed projects, mostly in the Philadelphia region. In addition to photographs of building fronts, the publication includes detailed photos that show the major terra cotta units for many of the buildings. The terra cotta is often shown with a glazed finish, and detail shots show use as a material hung from a steel frame structure.

Midland Terra Cotta, Midland Terra Cotta Co., Chicago, circa 1920

This catalog is a set of 100 plates with architectural illustrations and photographs of architectural terra cotta. The drawings show how the terra cotta units could be used in both bearing wall construction and mounting on a structural steel frame.

Store-fronts in Architectural Terra Cotta, New Jersey Terra Cotta Co., New York and Perth Amboy, N.J.,circa 1920

This delightful catalog features both architectural illustrations and photographs of smaller terra cotta commercial buildings. Storefronts like these lined America’s main streets and urban shopping centers.

The Northwestern Terra Cotta Co. Chicago, Northwestern Terra Cotta Co., Chicago, 1925

This catalog highlights major projects and displays illustrated plates of terra cotta details. The Northwestern Terra Cotta Co. produced the terra cotta ornament for buildings designed by Louis Sullivan. Terra cotta elements that evolved from Sullivan’s original designs later became stock units that found widespread use in smaller commercial building façades.

Stock designs in Architectural Terra Cotta, Winkle Terra Cotta Co., St. Louis, Mo., circa 1920

This document is typical of stock design catalogs, showing standard elements and details for individual assemblies including cornices, door surrounds, and even fireplaces. Most of the stock elements in this catalog are for use in bearing wall construction.

Architectural Terra Cotta—The Store, National Terra Cotta Society, New York, 1915

Part of a five-part brochure series on building types, this promotional piece from the National Terra Cotta Society showcases examples of store buildings across the U.S. with terra cotta façades. The remainder of the series focuses on schools, theaters, banks, and garages.

Architectural Terra Cotta—Theaters, National Terra Cotta Society, New York

As part of the National Terra Cotta Society's showcase series, this catalog provides examples of performance spaces and movie theaters across the U.S. with terra cotta façades.

American Terra Cotta, American Terra Cotta, Chicago, 1940

This small brochure shows the transformation of architectural terra cotta into a “streamline modern” material. Smooth surface clay tile with bold colors were “the modern terra cotta facing.”