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The central library could get taller. (rendering from savedclibraries.org)

Over the past week, a panel of real estate, marketing, and library experts have been interviewing dozens of local figures, pouring over market statistics, and touring the surrounding neighborhoods to figure out what to do with Washington’s central library. The experts, coordinated by the Urban Land Institute at a cost of $125,000, evaluated three scenarios: The library remaining in Mies van der Rohe‘s landmark building as the sole tenant, another tenant coming in to share the space, and the city selling the building and moving somewhere else entirely.

This morning, they came back with their recommendation: Add two floors on top of the four that already exist, and lease it to somebody else, which would generate between $4.1 and $5.5 million annually in rent. The co-tenant would have their own entrance on the northeast corner. That, in turn, could help finance renovations on the rest of the building, estimated to cost between $200 and $250 million (which also drags down the potential return to the city should it choose to sell the building outright; the panel estimated it would only fetch between $58 million and $71 million in the current market).

What? Won’t the historic preservation community scream bloody murder to alter the landmark so drastically?

Probably not, according to my informal poll of mucketymucks after the presentation. As Kriston Capps so lyrically stated last year, the central library is a “Mies cut off at its knees.” Most of his other boxy buildings were taller, and so the proportions would work out. Furthermore, the design-centered panelists suggested that two additional floors could have an inner atrium, which would allow light to pour into spaces that in the lower floors are currently enclosed and unusable. It would be an engineering challenge, but allowing more floors could be the only action at this point that would allow the library to remain in the lower floors (given that administrative functions would move off site, likely to some needy spot east of the Anacostia).

A sketch of how things would work.

Mostly, said panelist and historic architect Mimi Sadler, van der Rohe wanted his spaces to be flexible, and to be used. “If adding two floors makes this building viable into the future,” she said, “I’d say Mies would be out there applauding.”

The full powerpoint presentation—-including a sketch of how the floors would sit—-will be available this afternoon [UPDATE: Here it is!], and the panel’s full report within two months.