Thornton Tomasetti worked closely with architects Goettsch Partners and developer Clayco, to help deliver Zurich Insurance Group‘s new 784,000-square-foot North American headquarters in Schaumburg, Illinois.
As sustainability consultant for the project, Thornton Tomasetti played a key role in developing and analyzing project strategies to achieve LEED Platinum certification and a 62.7 percent whole building energy cost savings.
The building includes multiple green roofs, energy efficient technologies, rainwater harvest and re-use, accommodations for electric and low-emitting vehicles and native landscaping with more than 600 trees on 40 acres.
To verify performance and optimize the façade for reduced energy consumption, Thornton Tomasetti provided computational fluid dynamics (CFD) modeling on the ventilated double-wall façade on the lower portion of the south-facing, three-story cafeteria. The 4.5-foot-wide double wall with integrated shades is designed to reduce solar gains in summer, while increasing the gains in the winter, as well as to improve daylighting, resulting in an estimated 33% energy savings in the adjacent space.
The building is composed of three primary “bars” stacked and arranged to maximize views of the surrounding landscape and to optimize solar orientation. Thornton Tomasetti provided detailed daylighting studies using Honeybee software to evaluate the effects of automated interior blinds and fine-tuned the depth of the exterior shading devices for each orientation. The analysis optimized the depth of the shades for energy performance, which reduced peak solar gain for better thermal comfort and the size of the mechanical systems.
“Thornton Tomasetti’s expertise in high performing building systems was instrumental in achieving our goal of LEED Platinum certification,” said Joseph Dolinar, partner at Goettsch Partners. “The firm’s energy modeling of the building, targeted studies of façade shading concepts, daylighting studies and double-skin wall analysis enabled us to optimize the façade design and greatly improve the overall building energy performance.”
The Zurich’s new headquarters is the largest LEED Platinum Core and Shell v2009 project in the U.S. and the only LEED Platinum CS v2009 project in Illinois.