600 Mass Avenue

Featuring the Finest Materials, Systems, and Green Spaces
Washington, D.C.
Gould Property Company and Oxford Properties Group
400,000 Square Feet
Year Completed: 
LEED Platinum

The building features Class-A office space, a two-story glass atrium in the lobby with stone flooring, and a four-story atrium from the second floor ascending to the fifth floor. The primary roof  incorporates green spaces with planters and heavy vegetation, and offers views of the Capitol and the Washington Monument. In addition, the building features six significant terraces throughout.

The core and shell of this 400,000 rentable square-foot office building is comprised of a concourse level and three below-grade levels of parking. Designed by CORE™, the 10-story building is  clad in curtain wall glazing, composite metal panels, brick veneer, and a stone façade.

In addition to constructing the building, Clark also renovated a previously relocated historical townhouse, which is on site. Renovations include the restoration of the existing masonry exterior walls, and the installation of wood windows and doors, roofing, and base-building mechanical, electrical, and plumbing systems.

600 Mass Avenue boasts LEED Platinum certification.  Among its many sustainable features are five individual terraces that provide tenants with easy outdoor access, high performance windows that allow daylight to enter the building while blocking the sun's heat, and a rooftop garden that provides shaded outdoor space throughout the seasons.  Two rainwater cisterns also collect over 93,000 gallons of water for reuse. During construction, Clark used locally-sourced materials and managed an intensive recycling program.   

Clark self-performed the excavation and support of excavation for the project.

WBC Craftsmanship Award - Underpinning, Foundations and Excavations (Clark Foundations)