At 1.5-million ft2, Seattle Convention Center’s (SCC) additional building, Summit, is the single largest construction effort in Seattle history. Working in collaboration with Seattle’s LMN Architects, the addition project doubles SCC's current capacity and will introduce a new 30-story residential tower and 16-story office building, along with a number of public spaces. Developer Pine Street Group estimates that the expansion will generate as many as 2,300 new jobs and bring the city an additional $200m in visitor spending. Located in the heart of downtown, the project has transformed several under-utilized blocks into a thriving mixed-use district and improves connections between Capitol Hill and the waterfront.
Arup performed mechanical, electrical and plumbing engineering and fire/code consulting for the SCC addition, which started construction in 2018 and opened to the public in early 2023.
Maximizing sustainability and cost savings without compromising design
The SCC expansion has achieved new national benchmarks in convention center sustainability. The project is targeting LEED Gold and has been awarded the Vision Award for Water by the Seattle 2030 District. To help the project meet these goals, our MEP experts worked closely with the design team to develop systems that redefine performance standards.
$2bn project cost
2,300projected new jobs created
$200mprojected visitor spending
Strategic MEP solutions
The original convention center’s open concept pre-function areas were challenging to heat and cool, particularly during the winter. The new addition’s lobby and circulation area call for even greater vertical stacking and connectivity. To ensure that the space achieves the required comfort level while reducing energy use, we designed a hybrid heating and cooling solution that combines the benefits of variable air volume (VAV) and radiant floor heating and cooling. In addition to being more sustainable than an industry-standard approach, this solution enabled the design team to maximize ceiling heights and cut floor-to-floor heights, reducing mechanical construction costs by $1m. Together with other energy efficiency measures, including a large solar PV array on the ballroom roof, the project achieves 38% operational carbon emission reduction compared to baseline performance.
We also worked closely with the project team to identify “found” space for a large rainwater harvesting vault, located below the loading dock truck ramp. This system will help recapture rainwater from the adjacent office tower roof and maximize rainwater reuse while minimizing cost by connecting the system to the restrooms with the most expected use throughout the year, reducing regulated potable water usage by 50%.
Supporting safety and design
Our fire and life safety experts brought more value to the project by developing a performance-based fire engineering strategy that reduced smoke exhaust and makeup air by more than 1 million cubic feet per minute, enabling the architect to achieve the desired space usage and interconnectivity goals. The performance-based design developed reduced exit widths using modeled egress timing and computational fluid dynamics fire simulations. The team worked closely with the Seattle Fire Department and Seattle Department of Construction and Inspection to ensure all life safety and fire-fighting needs were met while allowing over 200ft of vertical connectivity from the below grade exhibit hall to the ballroom level at the top of the building.
Arup is proud to have played a role in helping the SCC addition achieve new standards in sustainability and performance within a new paradigm of vertically programmed, urban convention centers. ” Anne Marie Moellenberndt Associate Principal
Streamlining energy performance analysis
Recent changes in Seattle’s envelope systems requirements meant that early code studies were crucial to achieving compliance. The Arup team evaluated multiple approaches in the early phases of design, using Rhino and Grasshopper. We also created custom tools to generate building performance models that leveraged the benefits of Rhino and EnergyPlus. This approach aided the client in efficiently vetting various mechanical and architectural design options, and helped to identify the path with the lowest cost and least risk.
BIM: Improving efficiency and collaboration
To accelerate coordination and enhance constructability early in the design process, the Contractor’s BIM detailers worked alongside Arup staff in our offices to co-create a detailed BIM model for the project. This approach allowed the construction team to provide critical constructability input–of particular importance when single duct fittings can weigh 20,000lbs.