1717 K Street

A Landmark Washington, D.C. Location
Washington, D.C.
Connecticut & K Associates LLC
Pei Cobb Freed & Partners
Additional collaborations with Pei Cobb Freed & Partners:
WDG Architecture, PLLC
386,000 Square Feet
Year Completed: 
LEED Platinum

Located in the heart of Washington, D.C., 1717 K Street blends luxury and sustainability. The home of law firm Arent Fox, the project features Class-A office space within a LEED Platinum building.

1717 K Street is a 12-story office building at the intersection of K Street and Connecticut Avenue in Washington, D.C., across from the Farragut North Metro Station. The project also includes ample ground-level retail and four levels of below grade parking. Joining a handful of area office buildings with the LEED Platinum designation, the project team ensured that the green features met their client's standards. Clark also completed the interior fit out for tenant Arent Fox.


1717 K Street reduces energy use by over 20 percent compared to a building built to code minimum. The curtain wall system that faces Connecticut Avenue and K Street is comprised of stainless steel, stone, and glass. The owner requested the manufacturer add argon gas between panes of glass, to make the stunning facade more thermally efficient.

On top of the building is a green roof of more than 16,000 square feet, and  the building's efficient MEP systems contribute to a total water savings of over 40 percent. Among the project’s most innovative sustainable elements are three water-cooled frictionless chillers that use magnetic levitating bearings instead of oil. These chillers require less maintenance and generate less noise. They can be utilized in series or parallel, depending on the season and time of day.


While 1717 K Street's central location benefits its tenant Arent Fox, the constraints posed numerous challenges for the excavation process and foundation design. Clark Foundations worked around existing utilities below K Street to the south, an alley that had to remain open to the north, and buildings with below-grade levels to the north and west. The the east, the team installed tie back bracings in close proximity — many of them within 15 feet — to the Farragut North Metro Station, an active and heavily-trafficked station. This demanded great care in drilling them accurately; if they were over drilled or installed at the wrong angle, they would have damaged the station. They also worked closely around a highly sensitive and critical fiber optic ductbank that services the White House, located nearby.

ABC of Metropolitan Washington - Excellence in Construction Award - Commercial, $40M+
USGBC - NCR Project of the Year (Core & Shell Building)
WBC Craftsmanship Award - Underpinning, Foundation, Sitework
WBC Craftmanship Awards - Curtain Wall
WBC Craftmanship Awards - Exterior Stone