USACE Federal Center South Building 1202

Seattle, WA
LEED Platinum
Services/Project Type
Structural Engineering
Civil Engineering

Federal Center South Building 1202 is the result of both the 2009 American Recovery and Reinvestment Act funding (ARRA), and the U.S. General Services Administration’s (GSA) Design Excellence program which was established to procure the nation’s best engineers and architects in order to achieve the most innovative and high performance design in federal government building projects. Building 1202 transforms an 8.9 acre brownfield site into a highly flexible and sustainable 209,000 SF regional headquarters for the U.S. Army Corps of Engineers (USACE) Northwest District, which is in the top 1% of energy efficient office buildings in the country.KPFF provided civil and structural engineering services for this award-winning design-build office building that sits along the Duwamish River in South Seattle. Some of the great engineering contributions include:

A perimeter diagrid was employed to serve against the progressive collapse design requirement. The diagrid consists of sloping columns and spandrel beams with bolted (pinned) connections between the members that creates an efficient and inherently redundant structure. The diagrid is celebrated as an integral part of the building’s architectural expression as well as a physical manifestation of the Corps’ motto of “Building Strong”.

Composite Timber‐Concrete Beams
An innovative approach using composite timber-concrete beams was implemented to construct the entire central "Commons" with the available on-site reclaimed timber supply. 

Energy Piles
A majority of the building’s pile foundations contain ground source heat exchange loops, creating “Energy Piles”, that form the backbone of a geothermal system that works in concert with the building’s high performance mechanical systems. This is one of the first projects in the region to combine the use of geothermal heating and cooling systems with structural piles.

Progressive Collapse and Blast
The diagrid was constructed as a result of a primary design requirement that the building be designed to resist progressive collapse in the event of a terrorist attack. Enclosures were designed for blast criteria.

Drainage & Site Sustainability
One of the primary goals was for the drainage design to mimic natural drainage systems to the greatest extent possible, while achieving required water quality and quantity controls. Leveraging the site design, surface features and topography route runoff around the site through weired bioretention facilities, allowing infiltration and evapotranspiration of the stormwater prior to discharging to the Duwamish River.
• Project increases pervious coverage from 0% to 66% 
• Retains 95th Percentile Rainfall Event
• Treat 99% of site through WQ facilities, including 39,000-sf of bioretention facilities

Awards & Recognition

  • 2014 Honor Award, Commercial Office Building of the Year, Wood Works
  • 2013 Outstanding Project Award, New Buildings $30M - $10M National Council of Structural Engineers Associations
  • 2013 Committee on the Environment (COTE) Award, American Institute of Architects
  • 2013 DBIA Office Buildings, National Design-Build Award
  • 2013 ENR Best Projects, Government/Public Buildings, Best Project
  • 2013 Excellence in Structural Engineering Award, National Council of Structural Engineers Associations
  • 2013 Green Washington Award Winner, Special Recognition for Cutting-Edge Buildings, Seattle Business Magazine
  • 2013 National Design-Build Award, Design-Build Institute of America
  • 2013 Office Development of the Year- Public, NAIOP Night of the Stars