Two-acres of living roofs that absorb rainwater runoff and a one-million gallon rainwater storage tank are just a few of the elements that have helped the Bill & Melinda Gates Foundation campus earn a Leadership in Energy and Environmental Design for New Construction (LEED – NC) Platinum certification. Announcement of the world’s largest, non-profit LEED-NC Platinum building was made in a recent news release.
The 639,860 square-foot campus is located in downtown Seattle, across from the Space Needle. Taking advantage of the wet climate of Seattle in the form of water conservation is a huge part of the building’s design. A one-million-gallon rainwater storage tank is located underneath the campus. Water runoff is collected in the rainwater storage tank, cleaned of pollutants and filtered back into the campus for reflecting pools, irrigation and toilets. The campus’ potable water use is reduced by nearly 80 percent.
Additional green features of the campus include a roof-mounted solar energy system which provides energy for more than a third of the hot water use. Below the surface is a 750-thousand gallon water storage system that minimizes energy used to cool buildings by chilling stored water at night for recirculation during the day.The building’s overall energy use has been reduced by nearly 40 percent.
The building, which was originally completed this past spring, replaced what had been an asphalt parking lot. It returned what is said to be more than 40 percent of the site back to green space. Taking up nearly 640,000 square feet of space, this large-scale sustainable architecture project was designed by NBBJ and had originally be targeted for LEED Silver.
It is believed the the initial investments made in what is seen as a 100 year, energy efficient building will pay for itself in less than 30 years. The project reportedly was able to recycle construction debris at a rate of 97 percent, while over 20 percent of the project was built with recycled content and regional materials. 21 subcontractors extracted and manufactured materials within 500 miles of the job site.