Issue 3 of 2014

In its first year, the Federal Center South Building reduced energy usage by 40 percent.

As part of federal initiatives to increase the energy efficiency of government buildings, the U.S. General Services Administration (GSA) invested $72 million to revamp an old industrial site and build a new headquarters for the Seattle, Wash., U.S. Army Corps of Engineers (USACE). The location, classified as a brownfield site, was previously occupied by a warehouse built in the 1940s by the USACE, which had gone through several private owners before being returned to the government. This left the design-build team of Sellen Construction and ZGF Architects LLP with the task of not only creating a 21st Century office building, but bringing the site up to environmental standards.

The GSA’s goal was to create a workspace that would balance form and function, meet demanding performance requirements and set new standards for sustainable, cost-effective and energy-efficient workspaces. As a goal, a LEED ® Gold certification from the United States Green Building Council was set as the minimum standard.

Design-Build Done Right

In many ways, the entire project exemplifies Design-Build Done Right, following many of DBIA’s best practices. The owner’s goals were established early in the process, with the design-build team communicating and working with the GSA to determine needs and desires. Sellen and ZGF had a history of teaming on projects which laid the foundation for creating an environment of cooperation and collaboration. In addition, the sub-contractors were involved early, greatly increasing the knowledge available to the team.

Calling upon the experience of the entire team — design-builders, sub-contractors and owners — the team was able to program, plan and design the entire project in less than 18 weeks. Since the owner had used performance requirements to specify what they wanted, but not how they wanted to achieve the result, the team had the freedom to innovate and leverage their broad knowledge base to deliver.

The advance planning paid off. Using BIM, the team was able to detect clashes and correct them before proceeding to construction. The team also used unneeded space in an adjacent warehouse to build mock-ups to test how things would look and function when built. These mock-ups were used to refine the design and to determine systems and finishes before ordering them.

Energy Efficiency, Sustainability and Innovation

Energy efficiency was a critical feature and again the design-build team rose to the challenge. The soil under the building is liquefied, which required that the building be set on piles driven at least 150 feet deep. While this would usually be a negative, Sellen and ZGF turned it into a positive. With the steel pipe piles going so deep, they provided geothermal wells that offer enough heating/ cooling water that the team could eliminate one boiler and one cooling tower, improving energy efficiency without sacrificing comfort. This is one of the first instances where geothermal heating and cooling have been combined with structural piles.

The team also used an exposed “diagrid” structure, which is not only durable, it allowed for a 15-to-20-percent reduction in the amount of structural steel needed around the outside of the building.

Verified Success

At completion, the GSA project manager, Rick Thomas, stated in a letter, “They not only delivered what they originally proposed during the design excellence competition phase, but they worked closely with the GSA to find ways to further enhance the project after they were awarded the project.”

GSA had specified that a portion of the contract amount would be held in escrow for a year to verify that the energy savings would meet their requirements. At the end of its first year of operation, Federal Center South met the standard set. Energy use was reduced by 40 percent, achieving an Energy Usage Intensity of 25, saving more than 18,350 million BTUs in that year.

“This project represents the next evolution in the design-build delivery model — one in which the client remains engaged in project decisions, honors beautiful design, and incentivizes and guarantees energy performance — all within a guaranteed price structure,” said Jack Avery, senior project manager and integrated delivery specialist for Sellen Construction. “For a long time, the industry has believed that it was not possible to deliver higher quality and more scope without impacting the cost and schedule. On Federal Center South, using design-build, we proved it can be done.”

Awards:

Design-Build Institute of America: 2013 National Design-Build Award
American Institute of Architects: 2013 COTE Top Ten Green Projects
Associated General Contractors: 2013 AGC Build Washington Awards, Construction Excellence, Public Project $50-$100 Million
Construction Management Association of America: 2013 Vertical Project Award
National Institute of Building Sciences, Sustainable Buildings Industry Council: 2012 Honor Award — First Place for High-Performance Buildings, Beyond Green High-Performance Building Award

Snapshot:

Owner:
U.S. General Services Administration, Acquisition Solutions Branch
Design-Builder and General Contractor:
Sellen Construction
Architect:
ZGF Architects LLP
Construction Manager:
Heery
Engineers:
WSP Flack + Kurtz, KPFF, Hart Crowser
Subcontractors:
University Mechanical, Sequoyah Electric, Site Workshop
Additional Team Member:
Gordon Plume