The E. Ross Adair Federal Building and U.S. Courthouse occupies a parcel of land bounded by Douglas Avenue and Harrison, Brackenridge, and Webster streets.
It is designed in the Stripped Classical style of architecture, which was frequently used for federal building design during the Depression era and was advocated by Louis A. Simon, who oversaw federal building design under Acting Supervising Architect James A. Wetmore.
It features classically inspired symmetry, massing, and materials, but without the abundant ornamentation that was common on some earlier styles of federal architecture.
Instead, its stylized decorative elements are characteristic of those found in Art Deco architecture.
The imposing building portrayed the dignity and stability of the federal presence during a difficult time in American history.

The building rises three stories above a basement and is clad in gray-buff limestone with a granite base and entrance steps.
Replacement aluminum sash windows are found throughout the building.
The facade faces east toward the entry plaza and Harrison Street.
The bays are divided by classically inspired columns with carved capitals in a stylized leaf pattern reminiscent of Corinthian columns.
Eagle motifs are found on metal spandrel panels that separate the first and second floors; limestone panels with simple medallions separate the second and third levels.
The building is topped by a cornice that contains the gutter system and features carved lion heads at evenly spaced intervals.

Projecting pavilions at each end of the facade contain entrances that are topped by original cast-aluminum grilles.
The door openings have stone surrounds with carved cornices containing stylized floral and leaf patterns.
Carved stone medallions containing eagle motifs are located above each entrance.

The interior contains several significant spaces that retain their historic finishes and features and continue to convey the grandeur of the building.
The entry vestibules have floors covered in contrasting marble that forms a central star design with a diamond-shaped border.
Walls are also clad in marble with molded door and window surrounds and fluted pilasters.
Built-in marble benches are below windows.
The pale marble is St. Genevieve Golden Vein and the darker marble is Verde Antique.
Elaborate plaster coffered ceilings glazed a rich golden brown top the space.

The postal lobby on the first floor features marble floors, marble walls, decorative plaster ceilings, and ornamental cast-aluminum door and window surrounds.
Although postal services are no longer located in the building, original postal window openings with cast aluminum surrounds and marble sills remain.
Above the postal windows are large transom windows with leaded glass.

The district courtroom on the second floor is another important space.
Its walls have dark green marble bases below mahogany wall panels with walnut burl inlay.
Ornate bronze grilles and wall sconces are original features.
The ornamental plaster cornice transitions into a plaster coffered ceiling with alternating octagonal and square designs that have been painted in a polychromatic color scheme.

One of the most impressive features of the site is the elaborate plaza along the Harrison Street facade.
The plaza is reached by granite steps that contain a landing with a flagpole with a simply decorated bronze base.
Integral granite benches form walls that enclose the plaza.
The rear plaza bench, which is 40 feet long, is carved with the signs of the zodiac on the back while the arms have carved stylized leaf motifs.
The E. Ross Adair Federal Building and U.S. Courthouse occupies a parcel of land bounded by Douglas Avenue and Harrison, Brackenridge, and Webster streets. It is designed in the Stripped Classical style of architecture, which was frequently used for federal building design during the Depression era and was advocated by Louis A. Simon, who oversaw federal building design under Acting Supervising Architect James A. Wetmore. It features classically inspired symmetry, massing, and materials, but without the abundant ornamentation that was common on some earlier styles of federal architecture. Instead, its stylized decorative elements are characteristic of those found in Art Deco architecture. The imposing building portrayed the dignity and stability of the federal presence during a difficult time in American history.
The building rises three stories above a basement and is clad in gray-buff limestone with a granite base and entrance steps. Replacement aluminum sash windows are found throughout the building. The facade faces east toward the entry plaza and Harrison Street. The bays are divided by classically inspired columns with carved capitals in a stylized leaf pattern reminiscent of Corinthian columns. Eagle motifs are found on metal spandrel panels that separate the first and second floors; limestone panels with simple medallions separate the second and third levels. The building is topped by a cornice that contains the gutter system and features carved lion heads at evenly spaced intervals.
Projecting pavilions at each end of the facade contain entrances that are topped by original cast-aluminum grilles. The door openings have stone surrounds with carved cornices containing stylized floral and leaf patterns. Carved stone medallions containing eagle motifs are located above each entrance.
The interior contains several significant spaces that retain their historic finishes and features and continue to convey the grandeur of the building. The entry vestibules have floors covered in contrasting marble that forms a central star design with a diamond-shaped border. Walls are also clad in marble with molded door and window surrounds and fluted pilasters. Built-in marble benches are below windows. The pale marble is St. Genevieve Golden Vein and the darker marble is Verde Antique. Elaborate plaster coffered ceilings glazed a rich golden brown top the space.
The postal lobby on the first floor features marble floors, marble walls, decorative plaster ceilings, and ornamental cast-aluminum door and window surrounds. Although postal services are no longer located in the building, original postal window openings with cast aluminum surrounds and marble sills remain. Above the postal windows are large transom windows with leaded glass.
The district courtroom on the second floor is another important space. Its walls have dark green marble bases below mahogany wall panels with walnut burl inlay. Ornate bronze grilles and wall sconces are original features. The ornamental plaster cornice transitions into a plaster coffered ceiling with alternating octagonal and square designs that have been painted in a polychromatic color scheme.
One of the most impressive features of the site is the elaborate plaza along the Harrison Street facade. The plaza is reached by granite steps that contain a landing with a flagpole with a simply decorated bronze base. Integral granite benches form walls that enclose the plaza. The rear plaza bench, which is 40 feet long, is carved with the signs of the zodiac on the back while the arms have carved stylized leaf motifs.
E. Ross Adair Federal Building and United States Courthouse