Credit: Darrow Montgomery

We know D.C. Get our free newsletter to stay in the know.

It’s not quite Brutalist. Unlike the hulking FBI and HUD buildings and the castle keep of the Hirshhorn Museum, 2501 M wears its concrete exterior meekly. It couldn’t really be called late modernist either, because it doesn’t have the sharp geometries, mirror walls, or other hallmarks of that style.

Built in the early 1980s, the eight-story West End building is a bland grid of precast concrete and deep-set windows of darkish glass—features echoed in structures all over D.C. The only detail that sets 2501 M apart from dozens of buildings of the same vintage is a quirk in its otherwise rectangular form: The mass of the top three stories protrudes over the five floors below, like a lid sliding over a cardboard box.

To Ron Ngiam, an architect with the Georgetown firm CORE architecture + design, the building looks like a mushroom—or it did, until recently. Ngiam and his colleagues are almost finished with an idiosyncratic renovation and expansion of 2501 M. They claimed the unused square feet on either side of the lower part of the building, its “stem,” with new glass bump-outs and also carved out space for a restaurant on the ground floor. What was headquarters for a nonprofit, the American Association of Medical Colleges, will be reborn this fall as luxury condos with a Nobu downstairs.

Condo conversions are par for the course in gentrifying D.C., but 2501 M is a stranger building than it seems at first glance. The top three floors, or the “cap,” are already condos and always have been. Back in 1979, before breaking ground, developer Mel Lenkin did some zoning-code math and realized he could combine what was then a high-demand use (commercial) with a less lucrative but still profitable use (residential) to maximize the floor area and his financial return. At the time, the city had to incentivize people to move downtown—if you can imagine—and Lenkin’s project fit nicely into the new C/R (commercial/residential) zoning category.

The residents of 2501 M’s existing condos have stayed put during the renovation, and CORE has worked around them, phasing the project carefully to minimize disruption and preserve access to the top floors. The design team combined what had been two separate elevator lobbies (one for the condos, one for the offices). But the biggest difference between an office building and a residential building is pretty simple: bathrooms. Dozens had to be added, and the architects drilled more than 2,500 new holes in the concrete floor slabs for running pipes and wires. “After we were done, the whole building looked like Swiss cheese,” Ngiam says.

They plugged the holes with materials such as carbon fiber reinforcement (which looks like duct tape, according to Ngiam) and reinforced the structure under the additional weight of the bump-outs. When the condos inside are done, workers will brighten the gray-brown exterior by applying a clingy acrylic coating called Granyte that’s flecked with black, white, and silver like the stone it mimics. The building will look sprightlier and more contemporary while still owning its ’80s pedigree.

The possibilities of building around the “stem” make this project unique, but in other ways 2501 M could be a bellwether for a huge number of buildings across the city. You know the ones, even if they’re hard to picture: boxy offices from the 1960s, ’70s, and ’80s, often with horizontal bands of windows or vertical concrete ribs and stocky columns at the base. If they seem interchangeable, it’s because many of them sprang from the same drawing board.

Credit: Darrow Montgomery

Vlastimil Koubek, a Czech architect who immigrated to the U.S. in the early 1950s, designed more than 100 buildings in D.C., including (no points for guessing) 2501 M. Among Koubek’s many other commissions were the Brutalist-light International Square and the Motion Picture Association of America building; two of the four buildings at L’Enfant Plaza; the renovation and expansion of the Willard Hotel; and Metropolitan Square (with Skidmore, Owings and Merrill), which takes up most of the block bounded by 14th , 15th, F, and G Streets NW.

Koubek was a developer’s architect, not a visionary. His Washington Post obituary from 2003 diplomatically described him as “an authority on drafting construction documents for commercial buildings.” Yet he played a major role in shaping the modern city of Washington. As a young man, CORE’s Ngiam worked for Koubek, fine-tuning details while his boss padded around the office in slippers, a lingering mittel-European habit. Ngiam estimates Koubek had a hand in up to 40 percent of D.C.’s current commercial building stock. In 1975, The New York Times reported that Koubek had designed about half of Washington’s office buildings since the 1950s. 

Koubek’s legacy, then, is both ubiquitous and unremarkable. As the bulk of his buildings reach their 30th and 40th birthdays, they look increasingly dated but fall short of landmark status. Yet it doesn’t make sense to tear them down—they’re solidly built and occupy prime sites. No wonder that many of them have received or are in line for extreme makeovers: the MPAA building, Metropolitan Square, International Square, and 1100 Vermont Avenue NW. 

In their fancy new clothes, a few nice architectural moments may be lost. Especially at the Brutalist corner plaza at K and 19th Streets NW, with its staggered setbacks, thicket of columns, and high and angled concrete wall announcing “International Square” in a space-age font. It represents Koubek at his best and would be compromised by any attempt to jazz it up. Most of Koubek’s buildings are more forgettable—but so too are the glass boxes that developers are making them over to be.

Unquestionably, though, extending the lifespan of these buildings is a good thing. From an environmental perspective, it means reusing old stock instead of ripping it out and sending it to the landfill and saving the copious energy required to build a brand-new structure. Also, buildings from this era have an important role to play in D.C.’s economy. 

Now mostly demoted to Class B status, they’re ideal for conversion into apartments, co-working suites, maker spaces, and (depending on ceiling heights) artist studios. The co-working giant WeWork partnered with developer Vornado to turn an aging Crystal City office building into its co-living experiment, WeLive, which opened last May. The company then took over two floors of Metropolitan Square for a 2,000-desk co-working location that opened in December. In Silver Spring, Koubek’s 1965 World Building now hosts both the maker space Catylator and a co-working venture called Creative Colony. 

In the end, 2501 M is an elegant solution to an uncommon architectural problem. But finding new uses for these tired buildings in general is a goal that deserves greater creativity and more architectural interest than it has gotten in the past, especially with affordable living and workspaces so hard to come by. The city needs old workhorses as well as new trophy buildings and prized landmarks to support a well-rounded economy and culture. Few are candidates for historic preservation, so designers and their clients should experiment with ways to reanimate them—at least as much as zoning regulations allow.