Analysis of the Bill and melinda gates foundation headquarter, seattle, USA
Research Paper about Energy modeling and design
Fall 2016, Energy Modeling and Design Process
Professor Dason Whitsett, the University of Texas at Austin
Collaboration with Isabel Albert and Johanna Molander
The Bill & Melinda Gates Foundation Campus is centrally located in downtown Seattle, Washington. The campus that serves as the headquarters for the Foundation features conference centers, data centers, offices and other amenities. The building houses about 2,000 occupants and was designed for 2,500 occupants. The 900,000 square feet large complex features two acres of green roofs and a one-million-gallon underground rainwater storage tank. The modern building that is designed to enhance employee work-culture through design has been awarded several distinctions, such as:
- LEED Platinum-NC 2.2, 2011
- 2013 ASHRAE Technology Awards, New Commercial Buildings–Second Place
- IES Illumination Awards, Award of Excellence, 2012
The total cost of the building was 500 million dollars and it was completed in 2011.
The foundation is a privately owned philanthropic organization working towards the enhancement of healthcare and reducing poverty worldwide. As the foundation is conscious of its impact on the world and as such the desire was to construct an environmentally conscious building. The aim was to mimic the foundations mission through the building, using a transparent curtain wall as a metaphor for its reputation as the world’s largest transparently operated private foundation in the world.
The campus’ downtown location puts it right next door to Seattle’s iconic Space Needle. The site, that formerly was a city parking lot, was chosen for its vicinity to public transit and other attractions. The site still has a parking; a garage that features a green roof designed to reduce energy consumption by approximately 40% as well as to reduce rainwater runoff by approximately 90%.
design strategies for sustainable building and energy simulations
outdoor space and community
Certain features were adopted as a means to maximize building energy efficiency and sustainability. Seattle is situated in a Marine climate zone in the northwestern corner of USA. As a result, the majority of the energy of the building will go towards heating as opposed to cooling. As a result of Seattle’s mild climate, the data center can operate 100% in outside air mode. Featured on site are excavated solar hot water panels. These are excavated tube panels added to the site midway, as a result of a change in predicted energy consumption. The panels are able to cater to approximately 50% of the campus hot water use. The site’s use of rainwater harvesting storage is able to store one-million-gallon and is used for irrigation and toilet flushing, reducing the water consumption by almost two million gallons annually. The system is designed to provide for 95% of the buildings annual non-potable water needs. The site also uses air cooled chillers in place of water cooled chillers as a means to reduce water consumption.
Although previously the site was used as a parking lot, before that the site was a wetland meadow situated between a lake and the ocean. As a result of the parking lot, much of the water previously habituating the site, was diverted to a municipal sewer system. A desire when designing the building and the site, was to try and restore the ecological system by reinstating the site’s water balance. One of the ways to reduce storm water flowing to municipal systems was the incorporation of the green roofs on top of the parking garages. Other methods involve designs that aim to copy the original characteristics of the site, such as wetland plantings and open water. Enriched soil mixes work to help the plant retain water in the plant root. The runoff from pavements and courtyards is diverted into the one-million-gallon storage cistern.
One of the most important characteristic elements on the building is the atrium façade. The transparent glass atrium serves as the primary entry, centrally located and programmatically versatile with grandeur to host receptions, banquets or other events.
It features two custom point clamped glass walls supported by a series of slender vertical cables, elegant by design and innovative in their responsiveness to programmatic demands, climatic context and an aggressive project schedule. The portal acts as a fulcrum between indoor and outdoor space, while establishing a strong connection to the immediate public realm and emphasizing the character of the Foundation. The atrium’s point-supported approach minimizes thermal bridges within the envelope and exemplifies the degree of high-performance that can be attained outside the traditional curtain wall facade paradigm to achieve a transparent environment with sustainable priorities.
The glass has a Low-E coating applied to the inner surface of the outermost pane to provide solar control and moderate the visible light transmittance characteristics with a relatively color-neutral coating. The insulated glass units with Low-E coating and argon gas are designed to reduce heat loss but permit solar gain – a solution most appropriate for a heating dominated climate such as Seattle. The extensive use of Low-E glass with argon throughout.
Another characteristic that the glass panels are 6’-8” wide x 7’-0” tall, fully tempered insulated units with glass edges set ¾” apart to create a joint filled with sealant to the exterior, foam backer rod infill, and a custom gasket lining the interior.
These fully-tempered insulated glazing units have a 1.7” nominal thickness composed of 0.370” SB70XL outer light, 0.50” argon-filled air space, and 0.80” laminated inner lite composed of two 10mm lites with a 0.06” interlayer. The insulated glass unit (IGU) edge deflection limit is L/140, or 0.6” along the 84” height of the typical panel.
Figure 3. Atrium space (left) and Atrium insulated glass unit composition (right). Courtesy of NBBJ.
The building includes acres of living roof that allow the building to achieve a series of sustainable and energy efficient goals: insulate, reduce the heat island effect, limit the rainwater and on-site and leads to water conservation through rainwater harvesting and allow a series of bird species to inhabit the place.
The landscape is designed to mimic the predevelopment characteristics of the site. Campus water features include wetland plantings and open water. The addition of appropriate soil enrichment mixes helps encourage absorption and retention of rainwater in the plant root zone.
Since the Foundation opened, birds have begun returning to the area, including a heron that has been spotted perching near one of the dark-water bogs. Runoff from sidewalks and courtyard paving is channeled into a 1-million-gallon rainwater storage tank, which provides non-potable water for irrigation and for toilet flushing. (This is allowed by code because the interior of the campus is private property.)
Façade system and Thermal performance
The Bill and Melinda gates Foundation headquarter is one of the largest structural glass facades in the Unites States. The Façade system is a significant role of conserving energy while letting in exceptional daylight and views. Because a glazing percentage was designed about 45% of gross wall area, it was significantly effective that there were a series of “sequence review” meetings attended by the mechanical engineer, the architect, and the controls contractor in early construction phase.
The typical type of curtainwall systems was processed by several mockups, which were visual, performance and blast testing. The thermal performance of the point-supported atrium glazing was conducted using computer simulation and physical testing in accordance with the National Fenestration Ratings Council (NFRC) standards to obtain the U-values and solar heat gain coefficient (SHGC).
From the viewpoint of a design aesthetics, unitized curtain wall system with open-joint play a major role of reducing maintenance and allowing effective daylighting. The façade system provides a breezeway between work places and exterior envelopes, and the breezeway is an inner circulation corridor and makes it possible for occupants to see the courtyard like natural environments. This space is also used to extended workplace with comfortable seating.
The new campus was completed in 2011 and it was awarded with a LEED-NC Platinum Certification, making their 639,860 square ft campus the largest certified non-profit building in the world. NBBJ led the design team, who equipped the building with 2 acres of living roofs, 1 million gallons of rainwater storage, solar systems and a long list of sustainable design strategies. Margaret Montgomery, who is principal and lead sustainable designer at NBBJ, said that this project started with the initial target of LEED Silver. They always focused on designing the right building for the occupants and surrounding community. With these sustainable strategies; energy efficient mechanical systems, daylighting sensors, natural ventilation, and high performance glazing, can make the building reduce energy consumption by 40% and this number means that it would make possible to maintain itself in 30 years.
Local and recycled materials are used during construction, which led to big payoffs for the building. Recycling efforts supported human environmental quality and regional ecological systems. After completion, there were post-occupancy workshops and an online survey in November 2011. 90% of respondents said the new space is very beneficial to work and meet with others. Especially they said that atrium space was significantly effective to communicate with other people. The headquarter’s sustainable strategies work well, meeting the needs of occupants and also reducing the energy consumption.
Alspach, Peter. “Impatient Optimism.” High Performing Buildings, (Winter, 2014): 16-26.
Bill and Melinda Gates Foundation. Building a Sustainable Campus, (January 05, 2011), Bill and Melinda Gates Foundation: http://www.gatesfoundation.org
Cheek, Lawrence W. “In New Office Designs, Room to Roam and to Think.” New York Times, March 17, 2012, http://www.nytimes.com/2012/03/18/business/new-office-designs-offer-room-to-roam-and-to-think.html
Vaglio, Jeffrey C. and Mic Patterson. “Sustainable Façade in Tension.” Building Enclosure Sustainability Symposium - Integrating Design & Building Practices, (2011): 280-91.
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