20 Massachusetts Ave NW Amenity Spaces

The $200 million redevelopment of 20 Massachusetts Ave NW transforms a 1970s seven-story federal office building into a vibrant, ten-story, mixed-use destination in the heart of Washington, D.C. The project repositions the architectural focus to porosity, visual prominence, and connectivity, successfully re-stitching an outmoded building back into the city’s urban fabric. Located at the crossroads of Massachusetts Avenue and F Street NW, the site enjoys privileged proximity to Union Station and iconic landmarks such as the U.S. Capitol and Supreme Court.

The reimagined 20 Mass includes 13,800 SF of street-level retail, the 274-key luxury Royal Sonesta Washington, D.C. Capitol Hill hotel, 183,000 SF of upper-level Class A office space, and a 14,500 SF penthouse ballroom, executive suite, and extensive green roof with 360-degree views. Hospitality-focused amenities, including a French restaurant, bar, lounge, and outdoor café, set the building apart, providing a unique experience for office tenants and visitors alike.

The renovation preserves the existing structure while adding three floors and extending the building’s footprint. A new glass curtainwall facade and two atria infuse the interiors with natural light, creating seamless indoor-outdoor connectivity. The design emphasizes sustainability and wellness, achieving LEED Gold and WELL certifications. High-performance glazing, low-flow water fixtures, and advanced HVAC systems contribute to a 20% reduction in energy consumption and a 40% reduction in water use. The project also features a 23,000-SF green roof and flexible floor plans to accommodate organizations of all sizes.

The result is a dynamic, sustainable, and inclusive workplace that blends modern design with historic inspiration, enhancing the pedestrian experience and contributing to the vibrancy of the Capitol Hill neighborhood.

Design: LEO A DALY
Photography: Michael Kleinberg