The McCormick Apartments consists of four stories, a mansard, and a raised basement. The entrance bow faces the intersection of Massachusetts Avenue and 18th Street, and the building measures about 80 feet, including the bow, along the five-bay Massachusetts Avenue side (southwest), about 111 feet on the seven-bay 18th Street side (west), and about 100 feet across the eight-bay P Street side (north). At one time, portions or all of the two east walls adjoined structures in row house fashion.
The top-floor apartment of the National Trust owned McCormick Apartments commemorates Andrew Mellon's national significance. He lived here from 1922 to 1932 while serving as the Secretary of the Treasury under Presidents Harding, Coolidge, and Hoover. After 1932 Mellon occupied the apartment intermittently until his death in 1937. Here he planned the National Gallery of Art and assembled the collection of artworks that he gave the Federal Government for display in the gallery. Mellon is remembered as a great Secretary of the Treasury for his financial program dubbed the "Mellon Plan" which stimulated the economic boom of the 1920s.
At the time that Mellon moved into the McCormick Apartments, the building was about 5 years old. About 1915, Stanley McCormick, a businessman who had purchased a large single-family house on this corner lot in 1906, decided to raze that dwelling and erect a luxury apartment, one of Washington's first. McCormick commissioned French-born architect J. H. de Sibour to plan the apartment, and de Sibour designed a five-sided, semidetached edifice that was well suited to its trapezoidal site. Inside, the first floor was divided into two apartments. Each remaining floor held one apartment, and servants' sleeping quarters occupied mezzanine levels. Rentals began in 1917, and in addition to Mellon, at various times, such illustrious figures as Robert Wood Bliss and Pearl Mesta occupied the building.
DC designation: November 8, 1964
National Register listing: April 3, 1973
National Historic Landmark designation: May 11, 1976