metropolitan park, phases 6, 7 & 8
Arlington, Va.
BEST PROJECT
Submitted By: Clark Construction
Owner: JBG Smith
Lead Design Firm: ZFG Architects
General Contractor: Clark Construction
Civil Engineer: VIKA
Structural MEP engineer: Thornton Tomasetti
MEP Engineer: GHT Limited Consulting Engineers
Subcontractors: Clark Concrete; Clark Foundations; Strittmatter Cos.; Miller & Long Concrete Construction; JE Richards Inc.; W.E. Bowers
With completion of Amazon’s second headquarters in April, the Metropolitan Park project team delivered 2.1 million sq ft of space in 39 months, at budget and on schedule. As the first phase of Amazon’s new headquarters, the Arlington, Va., project features two 22-story office buildings, including below-grade parking, street-level retail, 2.5 acres of new public spaces and more than a half-mile of protected bike lanes. The project also included the tenant fit-out of the entire development, with five amenity floors and 38 floors of office space.
General contractor Clark Construction joined the Metropolitan Park project team during design development, providing cost analysis on over 200 scope items. Thanks to those early efforts, the team was ultimately able to establish a GMP at the exact cost estimated in early design development meetings.
The Clark team studied major scopes and the workforce needed to complete the project before construction began in January 2020. Trade contractors were brought onto the team early for nine months to facilitate trade coordination as well as the early release and storage of materials. Several major scopes were divided among multiple trade contractors to maximize productivity, including concrete, drywall, painting, millwork and ornamental metals.
Clark worked closely with the design teams to significantly reduce cost impact for the client by finalizing a conference room design with the structural engineer just before concrete was placed. In addition, the team hung material for early-start mechanical and electrical scopes before the exterior curtain wall was staged on the floors.
Photo courtesy Clark Construction
Updated designs for the landscaping and public park were developed two years into the project. Clark sequenced early procurement of long-lead scopes, obtained permits and sequenced manpower to ensure all 50,000 plants and roughly 400 trees were installed to deliver the park, along with the buildings, in the spring of 2023.
A year and a half before substantial completion, finishes in both building lobbies were redesigned, including the addition of a “bird’s nest” feature. Clark worked closely with the design team to resequence ongoing lobby activities to minimize cost and schedule impacts.
Photo courtesy Clark Construction
The completed project runs with zero operational carbon emissions and is powered by 100% renewable energy. It features green roofs, 2.7 acres of rooftop terraces, electric vehicle charging stations and greywater and heat exchange systems. While under construction, it was the largest LEED v4 Platinum development in the U.S., according to Clark.
As part of its net-zero strategy, the team focused on the structure, setting a target of 10% less embedded carbon in the concrete than regional baseline. It was a significant undertaking, as the building features five times more concrete than a typical Washington, D.C., office building. The team’s solution called for using less portland cement and adding CarbonCure, which introduces recycled carbon dioxide into fresh concrete. The team issued a performance-based specification that allowed trade contractors, Clark Concrete and Miller & Long to each devise an approach to meeting the sustainability goal. The process exceeded expectations, ultimately achieving at least a 15% reduction in embedded carbon in the concrete.