U.S. Institute of Peace
Built on one of the last available sites at the northwest corner of the National Mall, the U.S. Institute of Peace (USIP) Headquarters is a functional office set within a monumental building. Notable for its eye-catching design and exceptional craftsmanship, the five-story concrete structure showcases two curving roofs designed to evoke the image of a dove.
The USIP Headquarters is structured as three distinct wings flanking two atria. A five-story curtain wall system at the front of one of the atria creates a grand hall. The top three stories of the Institute's headquarters contain office space for the organization's staff. Each office features an exterior window or an interior window overlooking an atrium below. Additional building facilities include a 230-seat theater, seven conference rooms, a 2,000 square-foot outdoor terrace, a two-level underground parking garage, and a landscaped exterior plaza.
One of USIP's most notable aspects is its roof, which emulates the wings of a dove. From the exterior, it appears white during the day and glows from soft light within at night. The roof is constructed of a steel frame and nearly 1,500 white translucent glass panels. The south roof has a 12,000 square-foot surface area and spans 80 feet between buildings; the north roof has a 7,500 square-foot surface area and spans 55 feet. One of the south roof's "wings" extends 40 feet away from the building toward the nearby Lincoln Memorial.
Clark carefully executed the installation of a three-sided glass and stainless steel tunnel for the two suspended bridges that span the two atria. There are 100 large panes of glass that measured 11 feet by 3.5 inches and eight-feet by 10 inches, which spanned the entire length of the two main atria. These piece had to be hand placed using specialized equipment engineered specifically for the project. The meticulous installation of the punched windows and storefronts allowed for the frameless window design to be successfully achieved.
From the careful placement of each roof pane to the selection of individual stone slabs, Clark emphasized precision throughout construction. Numerous local and national industry organizations recognized the high caliber of craftsmanship at USIP Headquarters.
Clark provided budgeting, constructability reviews, and value engineering from the schematic design phase through the construction documents, over the course of 29 months. These efforts resulted in a GMP that was less than the Client's budget — a tremendous achievement given the extremely high level of complexity in the design.
Throughout the preconstruction phase Clark engaged multiple subcontractors in different trades to provide their expertise in guiding the design towards constructable ways to achieve the intent. This was an effective approach to identifying qualified subcontractors and increasing the subcontracting community’s interest in the project.
Clark also led a formal design-assist procurement for the custom glass roof and and curtain wall on the project. The schematic design was competitively bid and Clark’s project team then managed the design-assist subcontractor through the design process, including architectural modeling, structural check modeling and visual & performance mock-ups. The custom curved roof could not have been designed without the invaluable expertise of the design-assist subcontractor.
The excavation and support of excavation, performed by Clark Foundations, faced logistical challenges, but was completed within the four-month schedule. There was 90,000 cubic yards of excavation, of which 65,000 cubic yards was rock. Clark Foundations worked around buried utility lines and structures, a 72-inch diameter sewer line, and an existing seven-foot-high buried steam tunnel. The project's location, adjacent to the U.S. State Department and two U.S. Navy buildings — one of which is located just 10 feet from the sheeting and shoring line — proved to be a challenge for the project team. Despite the large amount of rock excavation, Clark minimized disruptions to tenants in these neighboring buildings.
A concrete structure, USIP Headquarter's atypical layout made flawless concrete work both essential and extremely challenging. The cast-in-place and precast concrete often met along radial grid lines, which required the Clark Concrete team to carefully match the precast panels. The roof’s trellis, constructed entirely from architectural concrete, was cast using custom architectural forms and unique concrete vibration methods.
The USIP Headquarters was designed and constructed to achieve LEED certification, but through cooperation between the architect and Clark's project team, the project achieved LEED Gold. Elements relating to construction include waste management, recycled materials, local materials, low particle emitting materials, indoor air quality management, and commissioning to LEED criteria.
BIM was integral to the project’s success. Given the complex design, construction of the iconic glass roof and curtain wall required dedicated teamwork from design concept to final installation. The design phase was unique given it fully integrated BIM and final construction approval was based upon the 3D model rather than a 2D drawing set. In addition, the design-assist contract, which was awarded early in the design phase, allowed for maximum input from Clark and Seele, the structural engineer.