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Architecture

Hart Senate Office Building

Overview 

The Hart Senate Office Building is the third office structure designed and built to serve the United States Senate. Located northeast of the Capitol on a site bounded by Constitution Avenue, C Street, First Street, and Second Street N.E., it adjoins the Dirksen Senate Office Building.

Location: 

Northeast of the Capitol, adjoining the Dirksen Senate Office Building, site bounded by Constitution Ave., Second St., First St., and C St., N.E.

Date Occupied: November 1982

Area: 1,271,030 square feet

Earlier efforts to provide space for the Senate had included the construction of the Russell Building and the Dirksen Building. By 1967, the Senate began to experience a strain on its existing office facilities and initiated the process that led to the creation of the Hart Building.

In 1972, the Senate Committee on Rules and Administration asked the Architect of the Capitol to survey the space occupied by senators and staff and report on their work environment. In the decade and a half since the Dirksen Building had opened, the number of persons working for the Senate had grown from 2,500 to 7,000.

The Senate Office Building Commission authorized Architect of the Capitol George M. White to commission John Carl Warnecke & Associates to prepare studies. In addition to satisfying space and design requirements, the architects were required to preserve the neighboring 19th-century Belmont House.

Rendering of the Hart Senate Office Building by architect John Carl Warnecke, 1975.

Rendering of the Hart Senate Office Building by architect John Carl Warnecke.

On August 8, 1974, the Senate Office Building Commission and the Senate Committee on Public Works approved a proposed nine-story "extension" to the Dirksen Senate Office Building. The design included suites for 50 senators, with over one million square feet of interior space, including three floors of garage and service facilities, eight floors of offices, and a mechanical equipment floor at the top. A central atrium provides offices and corridors with light in an energy-efficient manner. To allow flexible office space design, Warnecke introduced a two-story "duplex suite," consisting of a Senator's office with traditional 16-foot ceilings and two staff levels that can be easily rearranged by the use of demountable partitions.

Construction of the Hart Senate Office Building in August 1979.

The first construction contract was awarded on May 20, 1975, excavation began in December 1975 and the building was named in honor of former Senator Philip A. Hart in August 1976. The first occupant, Majority Leader Howard H. Baker, moved into the building in November 1982.

Installed in 1986 in the building's atrium was the sculpture Mountains and Clouds by Alexander Calder, creator of the mobile. The matte black aluminum clouds, the largest of which weighs one ton, are suspended from the roof, revolving above the 39-ton steel mountains.

Last Updated: December 15, 2015