Joseph C. O'Mahoney Federal Center, Cheyenne, WY

The Joseph C. O’Mahoney Federal Center is representative of the Formalist style of architecture and consists of a two story building with a tower that projects up from the north end of the building. The building has a polished red granite base at the basement level. The first floor of the building is clad with reddish precast concrete panels with exposed aggregate. Above the first floor, the main building and the tower portion of the building have very different façade treatments. A solar screen composed of tan precast concrete tiles in a geometric diamond pattern wraps around the second story of the building but stops at the tower. The east and west ends of the tower are clad with tan precast concrete panels that are slightly proud of the panels at the first floor. Both of these elevations have two vertical aluminum grilles that run from the second floor through the eighth floor. The north and south elevations of the tower have tan precast panels at the ends and top that surround an articulated egg crate pattern of precast panels punctuated by windows. Penthouses with vertical aluminum panels are located on the roof of the main building and the tower.

Typical of Formalist architecture, the design has a simple arrangement of the building volumes that creates interesting visual relationships between the different building parts and the building as a whole. The building incorporates high quality building materials including marble, precast concrete and glass and has flat roofs, in keeping with Formalist design principles. Sun screens are also a common element in Formalist architecture and are present on both the main building and the tower. The main building has a concrete tile solar screen in a geometric pattern that wraps around the entire second story of the building and the tower has vertical aluminum sunscreens in a geometric pattern on the east and west ends. The north and south sides of the tower have concrete fins in an egg crate pattern which provides sun shading for the windows on this elevation. Other Formalist design elements that are incorporated into the building design include recessed windows, expression of corners and monumental scale. Formalist design ideas are also incorporated into the site which has a rectangular plaza located at the southeast side. The plaza has granite clad planters, trees, walkways and seating areas. Originally the walkways were composed of flagstone and concrete in a geometric pattern which has since been removed and replaced with new concrete. The intact interior spaces also exhibit Formalist design principles, especially the use of high quality materials including terrazzo flooring, marble wall panels and wood wall panels. Artwork is incorporated into the building in the form of an original bronze bas relief which is mounted on the wall in the tower lobby.

The main (east) building elevation faces Capitol Avenue and has two distinctly different cladding systems – the cladding on the main building and the tower. The main building has precast concrete panels punctuated by a series of large rectangular window openings. The solar screen runs continuously along the east elevation until it meets the tower. The tower portion of the building projects east from the east elevation of the main building and the south elevation of the tower has precast concrete panels in an articulated egg crate pattern. The east elevation of the tower has red precast panels at the first floor with tan precast panels above it. There are precast concrete tie back covers at the corners of the panels. There are two vertical slots on the east elevation of the tower for recessed windows which are covered by an aluminum solar screen that runs continuously from the second to the eighth floor. Two aluminum seals and aluminum lettering stating the building name, function and address are located at the first floor on the east elevation of the tower. The polished red granite building cornerstone is located at the north end of the tower and is dated 1964. Aluminum letters identifying the Post Office are mounted on the east elevation of the main building. The east elevation has two entrances – one into the Post Office and one into the tower. The Post Office vestibule is located approximately in the middle of the main building and the tower entrance vestibule is located at the southern facing portion of the tower. There is another projecting vestibule that has had the doors removed and been converted to a window, located between these two vestibules. The vestibules have a polished granite base below aluminum storefront windows and flat roof with a ribbed aluminum fascia.

The majority of the north elevation is the tower though the west end of the elevation is the two story portion of the building. The first floor of the tower is clad with red precast concrete panels punctuated by an emergency exit door and a series of ten vertical window openings at the east end. The upper floors of the tower have tan precast concrete panels surrounding tan precast fins in an articulated egg crate pattern. The penthouse with aluminum corrugated panel cladding is visible above the concrete parapet of the tower. The west end of the elevation is two stories high and the solar screen wraps around this section of the building.

The west elevation is composed of the two story main building with the west elevation of the tower and the second floor penthouse stepped back from the west edge of the building. The first floor of the building has red precast concrete panels punctuated by various man and garage doors. A loading dock, installed in 1980, steps out from the elevation and has a slightly rougher finish than the precast panels on the original building. At the south end of the elevation, the concrete foundation is exposed at the garage entry doors and above them the elevation is clad with the polished granite base and precast concrete panels with a horizontal strip of windows. At the second floor, the solar screen constructed of tan precast concrete tiles runs across the entire west elevation. The solar screen is held off the building by stainless steel attachments and conceals the window openings behind it. The west elevation of the tower is similar to the east and is clad with tan precast concrete panels with two recessed vertical slots for windows shaded by continuous aluminum grilles. A tan brick chimney projects above the roof line. The penthouse on the second floor roof is clad with vertically corrugated tan aluminum panels.

The south elevation is clad with a red polished granite base with red precast concrete panels at the first floor and the solar screen above that. A series of ten vertical windows is located below the solar screen on the west end of the elevation.

Interior spaces on the first floor have been greatly altered from their original design with the exception of the first floor lobbies. The lobbies retain their original terrazzo flooring and marble wall panels. The second floor corridor, courtrooms and a judge’s chamber are still mostly intact and have been minimally altered over the years. The corridor retains the original terrazzo flooring with an integral coved base, marble panel wainscot and plaster walls. The courtroom has the original decorative plaster and acoustic tile ceiling finish, wood wall paneling, judge’s bench, clerk’s desk, jury box and public seating benches. The judge’s office retains the original wood wall paneling and layout and the adjacent library also retains the original wall paneling and many of the original bookshelves.

The city of Cheyenne was platted in July 1867 and was originally in what was called the Dakota Territory, and later the Wyoming Territory. It was named Cheyenne after the Native American Cheyenne nation. The first charter for the government of the City of Cheyenne was established on August 8, 1876, and the next month a mayor was elected. A Federal Building was constructed in Cheyenne in 1932 and by the 1960s, the federal agencies had outgrown the available space in the Federal Building so a new facility was needed. Funds were gathered and the planning and design of the Post Office & Court House (later named the Joseph C. O’Mahoney Federal Center) began. Two architecture firms, Porter & Porter and J.T. Banner & Associates, Inc., were hired to design the Post Office and Court House. J.T. Banner and Associates was established in 1947 by Joseph T. Banner at Laramie, Wyoming. The firm offered engineering, architectural and consultation services. The firm also designed the Dick Cheney Federal Building in Casper, Wyoming which was constructed from 1968-1970.

The Post Office and Court House occupies a city block bounded by West 21st Street, West 22nd Street, Capitol Avenue and Carey Avenue. Previously the block was occupied by a church and various other buildings. The final plans for the Post Office & Court House are dated March 3, 1963. The building cornerstone is located on the north edge of the east elevation and is dated 1964 and the building dedication occurred in 1965. The final construction cost was $4,211,152.

Between 1967 and 1973, the building was renamed the Joseph C. O’Mahoney Federal Center. Joseph C. O’Mahoney was a Wyoming senator was appointed to the U.S. Senate in 1933 to finish serving the term for John B. Kendrick who passed away while in office. O’Mahoney was elected to fill this vacancy in November 1934, and was reelected several times. In 1953, he returned to practicing law and in 1954 was elected to fill the vacancy in the U.S. Senate caused by the death of Lester C. Hunt and served until January 1961.

Description Architect
1963 1965 Original Construction Porter & Porter and J.T. Banner & Associates, Inc.
1966 Freeze Protection Equipment GSA Region 8
1966 Landscape Sprinkler System Plan GSA Region 8
1966 Landscape Sprinkler System GSA Region 8
1966 Catwalk & Ladder Details GSA Region 8
1967 New Stairwell Door GSA Region 8
1973 New Opening for Conveyor GSA Region 8
1973 Dock Lift GSA Region 8
1974 Partial Interior Painting GSA Region 8
1975 New Garage Doors GSA Region 8
1975 Painting of Interior Spaces GSA Region 8
1975 1976 Fire Safety Provisions GSA Region 8
1979 New Burners GSA Region 8
1979 Handicap Provisions GSA Region 8
1980 US Postal Service Loading Platform GSA Region 8
1980 Fire Safety & Emergency Repair GSA Region 8
1981 Remodel U.S. Attorney's Office GSA Region 8
1981 Roofing GSA Region 8
1981 Relocate Bankruptcy Court GSA Region 8
1982 Solar Domestic Water Heater GSA Region 8
1982 Fire Alarm Fire Engineering Co., Inc.
1982 Elevator Fire Capture Controls GSA Region 8
1982 Energy Conservation Retrofit GSA Region 8
1983 Court Facilities GSA Region 8
1984 Enclose Mailing Platform US Postal Service GSA Region 8
1984 Office Renovation for U.S. Marshal GSA Region 8
1984 Asbestos Abatement GSA Region 8
1985 Fire Alarm System Modification GSA Region 8
1986 Modify HVAC System GSA Region 8
1989 ATF Remodel GSA Public Building System
1989 Revised Layouts GSA Public Building Service
1989 Court Alterations Edwards & Daniels Associates
1989 Modify HVAC System GSA Region 8
1990 Snow Meter Repair Edwards & Daniels Associates
1991 U.S. Marshals GSA Region 8
1991 Boiler Replacement Silver, Naylor & Associates
1992 Modernize Elevators Silver, Naylor & Associates
1994 Replace Cooling Tower Merrick
1995 Replace Chillers, Cooling Towers, and EMCS Merrick
2000 Fire Alarm System Replacement and Upgrade Rolf Jensen & Associates, Inc.
2000 2003 ISA for USMS EFT Architects
2001 United States Postal Service Permanent Facility Remodel Tobit & Associates, PC
2001 2nd Floor Abatement Oz Architecture
2002 First Impressions Project EFT Architects
2002 Fire Alarm System Simplex Time Recorder Co.
2003 Snow-Melt System Replacement Project EFT Architects
2004 US Attorney Tenant Remodel CTA Architects Engineers
2006 Generator Replacement CTA Architects Engineers
2007 Roof Replacement EFT Architects
Last Reviewed: 2021-09-14