20 Mass: Transforming a Former Federal Building Into a Mixed-Use Destination

20 Massachusetts Ave NW, Washington, DC

RMR reimagined 20 Mass from a former government building into a vibrant, mixed‑use destination in Capitol Hill. Delivered in 2023, the project activates the site with top‑floor offices featuring dramatic city views, a 271‑key Royal Sonesta luxury hotel, chef‑driven restaurants and street‑level retail, turning a legacy asset into a marquee address.

By expanding the structure, modernizing systems and curating a high‑impact mix of uses, we positioned 20 Mass to energize the streetscape, attract premier tenants and guests and perform across cycles.

Conversion strategy

We redeveloped and expanded the building, upgraded core systems and integrated wellness and sustainability from the start - earning LEED, WELL and ENERGY STAR certifications. Our teams coordinated design, construction and leasing to compress timelines, manage complexity and deliver a flexible, future‑ready asset. Property uses include:

Office: Delivered Class A office floors with panoramic views, modern infrastructure and direct access to premium amenities that support productivity and engagement.

Royal Sonesta Hotel (271 keys): Anchored the project with upscale hospitality, driving daily activity and elevating the guest experience.

Retail & F&B: Curated chef‑driven concepts and activated retail to bring energy to the block and connect seamlessly with the neighborhood.

Amenities: Elevated the experience with an amenity penthouse and roof terrace, conference facility, fitness club, bike storage, EV charging, valet parking and branded food & beverage.

Strategic impact

20 Mass now anchors a key corridor in Capitol Hill. The project boosts daytime and evening activity, attracts office users seeking high‑amenity environments and draws visitors with a luxury hotel and destination dining. The result: a revitalized, mixed‑use landmark that strengthens the neighborhood and drives durable performance.