A thoughtful, creative design process successfully resolved disparate challenges of modern code-compliance, public safety, and building preservation while maintaining the building's operation, comfort and occupancy.
As part of the GSA's Design Excellence Program, Swanke modernized the Internal Revenue Service (IRS) building in Washington, DC. This monumental seven-story building, completed in 1936 and listed on the National Register of Historic Places, comprises 1.4 million sq ft (130,100 sq m) housing 2,700 employees.

The building was the first of seven super-block government office buildings completed in the Federal Triangle. The first federally funded urban redevelopment project of this magnitude, it provided the model for American city planning in the 1930s-50s.

Modernization occurred in four phases, over five years, while the building was fully occupied with existing systems remaining fully operational. Mechanical, electrical, plumbing, and life safety systems were upgraded and the existing floor slabs throughout the lower level demolished and reconstructed.

Exterior restoration included repairing and restoring windows, facade repointing and cleaning, and resetting limestone coping. A complete blast assessment was performed and, in response, a laminated system was installed within the existing historic window assembly, meeting a GSA Level C Threat.