CH-12-C013 -- Integrated DesignBuild Delivery Team Achieves Aggressive Building Energy Performance Goals ✓ Most Recent

As a 2009 American Recovery and Reinvestment Act (ARRA) funded project and part of the General Service Administration's (GSA) Design Excellence program, ambitious building performance goals were set for the new B12021 Redevelopment for the U.S. Army Corps of Engineers (USACE) Seattle District Headquarters. A highly integrated design- build team was essential to creating a high value solution that met the design, energy performance, budget, and schedule goals. From the outset, the building's form, dimension, and organization were shaped by EUI targets (30% below ASHRAE 90.1 2007 benchmarks, or 27.6 Kbtu/SF/yr). Because the project award was made via an accelerated design-build competition, the team had a mere 18-week window to advance the design to a level that allowed the contractor to guarantee a maximum price for delivery, with confidence that the building would perform as expected. This short timeline required a tightly controlled, highly-collaborative process that involved all team members from day one. As a result, the team quickly and efficiently shortlisted, developed, and refined a series of strategies for the site, building, and systems design. After project award, the early inclusion of a mechanical contractor and the proactive engagement of GSA enabled the team to continue to collaboratively optimize the design to further improve anticipated building performance. Currently, the building is predicted to use less than 22 KBtu/sf/year, 40% below the AHSHRAE 90.1 2007 benchmarks, earning an Energy Star Score of 100 (putting it in the top 1% of comparable buildings) and meeting the 2030 Challenge. The design-build team is contractually obligated to ensure that the project energy performance standards are achieved after one year of operation, with 0.5% of the total design-build contract value at risk. The team's analytic and research-based approach to design (including in-depth energy modeling) includes the following energy saving strategies and features:

• A high performance façade, optimized by orientation, that enables both a low energy chilled beam-based HVAC system and abundant daylight to reduce lighting loads
• The addition of a phase change thermal storage tank coupled with a groundloop heat exchanger to capture and reuse otherwise wasted thermal energy, furthering the efficiency of the water-based HVAC system.
• High efficiency lighting (0.7W/sf) with enhanced lighting controls