The historic Carnegie Library on Mount Vernon Square opened its doors in 1903 and was used as the city’s central public library for almost 70 years. Revitalizing the Beaux-Arts building involved carefully preserving the historic facades, reinstating the interior’s original footprint, and restoring early 20th-century detailing.
The interior preservation strategy relied on identifying hidden historic chases, shafts, and vertical pathways to invisibly add new building systems and lighting. The project team coordinated and documented the removal of load-bearing masonry walls and non-original floor slabs to transform the cloistered interior into an open, engaging space. The addition of a custom skylight above the historic light well and the removal of non-original slab infill have returned natural daylight to the central atrium. The grand south staircase and the Guastavino vault space in the basement of the building were both meticulously restored.
The building’s exterior was also completely restored: deteriorated marble elements were replaced with hand-carved replicas, sculptural elements were repaired, and the historic copper roof was restored. The project also resloped the K Street entry plaza on to provide accessibility and added a new grand entry stair on Mount Vernon Place.