In addition to maintaining the roof, Mortenson was charged with sav- ing the iconic glass curtain wall that every fan, visitor, and Seattleite will see walking by Climate Pledge Arena, while preserving the view of the Space Needle, cityscape, and more. To accomplish this, each glass panel had to be carefully marked, catalogued, and stored before reinstallation in its original location. Working towards Net Zero Climate Pledge Arena is working to be the first net Zero Carbon arena in the world, powered exclusively by renewable energy rather than natural gas. The arena will run solely on electric power for daily operations, eliminating all fossil fuels from the building and utilizing the first all-electric dehumidification systems in the NHL. This meant Mortenson had to replace natural gas infrastructure with electrical systems. From kitchen systems and concessions, to air handling units, and building conditioning – all systems were changed to be served by electricity instead of natural gas. Overall water usage is critical to limiting energy use and sustainability goals. Rainwater will be stored in a 15,000 gallon below-grade cistern and filtered as needed for the “rain to rink system.” Waterless urinals and low flush fixtures were added to increase water usage efficiency. The mechanical, electrical and plumbing (MEP) system was also de- signed with efficiency in mind. Energy recovery ventilators, serving all the locker rooms, collect 100 percent of the air that is exhausted and use the captured energy to preheat or cool the incoming air streams. Changing out gas to electrical conversion substations almost doubled the amount of electricity coming into the building, requiring more electrical equipment. With equipment in order, immediate decisions were needed. Luckily important changes were able to be made at the fabrication stage, and the custom electrical equipment production stayed on schedule. Next, situating heavy electrical gear presented a real space utiliza- tion conundrum. Mortenson and the design team needed to determine where the equipment was going to live. Typically, it’s located on the first floor, but construction sequencing hindered that possibility. The entire construction and design team needed to find the best location
that was cost and schedule efficient and required the least amount of rework, which resulted in a substation on an elevated metal deck. Renewable Energy The original 160,000 square-foot arena roof is historic and, as such, could not be used to host solar panels. Instead, solar panels are planned to be installed on the roof of the new atrium building entrance and on the facility parking garage. The energy generated by the solar arrays will be used to power to arena alongside additional renewable energy sources. Project Delivery The construction and design team used several tools to ensure design, construction and marketing efforts dovetailed together to create a seamless project delivery. Mortenson used 4D building information modeling (BIM) as a basis for multi-trade coordination and scheduling. The entire building was constructed virtually to aid with major trade system coordination. For instance, the steel team could use the model to track fabrication and installation tasks. Color coding was used to aid schedulers while tracking procurement, upcoming tasks, and com- pleted work. Using the 4D model, the MEP systems were modeled to not only assist in clash detection (field installation coordination) but also in prefabrication efforts. Changing horses in midstream to create a net zero arena was a major effort by the entire team. Mechanical and electrical contractors were essential in giving their input, as were the architecture and engineer teams that jumped in to determine construction sequencing. Climate Pledge Arena will be a beacon of corporate responsibility across the sports landscape. Together, Mortenson and Oak View Group are setting new sustainable standards for the built environment and inviting others to join The Climate Pledge to reduce carbon emissions for a better future.
GREG HUBER is Project Executive at Mortenson.
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may 2021
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