Volume 48, Issue 11- November 2013
Nothing But Net
Winners of the USGlass Green Design Awards
Green building, green designs and green construction are phrases often used loosely among the design and construction industry. Every building professes to be green these days, but what, exactly, makes it so? According to the Environmental Protection Agency (EPA), “green building is the practice of creating structures and using processes that are environmentally responsible and resource-efficient throughout a building’s life-cycle from siting to design, construction, operation, maintenance, renovation and deconstruction. This practice expands and complements the classical building design concerns of economy, utility, durability, and comfort.”
High-performance glass and glazing products play a significant role beyond their energy-saving benefits when it comes to green buildings. Glazing products can provide a high performance environment for the occupants, such as use of the space (view and daylighting, acoustics, etc); can minimize environmental impact; and provide renewable energy sources (i.e. photovoltaics), among others.
These points were all part of the criteria used in selecting the winners of this year’s Green Design Awards. The winners incorporate many of the design features enumerated by the EPA, and use glass and glazing significantly. They have not only earned at least some level of LEED® certification, but one is also seeking Living Building Challenge Certification (see sidebar, bottom right). These projects epitomize what a green building should be—and set the bar to which others will strive.
Phipps Conservatory and
Surrounded by gardens, nature and the environment, everything about the Phipps Conservatory and Botanical Gardens, Center for Sustainable Landscapes (CSL) is green. In fact, the 24,000 square-foot building is striving to become one the world’s first certified “Living Buildings,” designed to consume zero energy. In addition, the project was awarded LEED Platinum certification from the U.S. Green Building Council (USGBC), earning 63 out of 69 possible points for a new construction under version 2.2. the project is also striving for four-stars Sustainable Sites Initiative certification for landscapes.
“The CSL was created to serve as a model for how we can work with nature to make our communities healthier, safer and more supportive of life,” says Phipps executive director Richard V. Piacentini. “With our LEED Platinum certification, we are excited to earn the first of three rigorous building and landscape standards, showing the world just how inspiring and practical green can be.”
Glass selection was critical to helping the center meet the certifications’ standards for energy use, aesthetics, and human health and comfort. The project features triple-glazed, dual low-E, insulating glass, mechanically controlled operable windows and skylight, aluminum sunshades and interior light shelves.
Piacentini says PPG glass was specified for the project because “we wanted a low-E, high-performing glass that provided state-of-the-art solar and thermal control and energy efficiency, while admitting maximum daylight.”
Chris Minnerly, AIA, LEED AP, principal of The Design Alliance Architects, agreed.
“One of the key aspects of glass selection is to balance the solar heat gain coefficient against the visible light transmission to get the best overall performance,” he explained. “The glass assemblies had to have the best UV transmission in certain light spectrums to facilitate the growth of plants.” Minnerly specified two triple-pane insulating glass units (IGUs) to meet performance requirements in different parts of the building. Sungate 500/clear glass combined with Starphire glass was installed above the sunshade and light shelves, while Solarban 60/Starphire glass was used below.
The center is designed as a long, window-lined rectangle to allow daylight to penetrate into the deepest parts of the interior space. Heating and cooling losses are offset by a thermal well system that captures about 70 percent of the center’s heating and cooling energy from the ground’s consistent 57°F temperature. The remainder of the center’s energy demand is satisfied through solar energy generated by building-integrated photovoltaic cells. Other glass-related energy performance features include: light shelves, louvers and overhangs to minimize summer cooling loads and contribute heat in winter; translucent window shades to reduce nighttime heat losses; and Brise-soleil screens and internal shades to reduce summer cooling loads and glare from low sun angles. The structure, which also houses the conservatory’s administrative offices and education and research programs, meets all of its energy and water needs without drawing a single watt from the grid or tapping water from the city of Pittsburgh.
The CSL is a global showcase of green innovation. It not only produces all of its own renewable energy with solar panels, geothermal wells and a wind turbine but also treats and reuses all water captured on site. Additionally, the CSL is surrounded by a restorative landscape highlighting a wide variety of native plants and a green rooftop garden with a view of Pittsburgh’s Oakland neighborhood. Other sustainable site features include a lagoon, rain gardens and constructed wetlands.
Project Name: Valley View Middle School
Valley View Middle School, which opened in 2012, was a replacement project for the Snohomish School District. Dykeman Architects’ original goal was to create a net-zero school, incorporating sustainability strategies such as highly efficient building envelopes, solar solutions, geothermal loops and rain water harvesting.
Dykeman, along with Dull Olson Weekes Architects, were selected to collaborate on the project. According to Dykeman, “The overriding goal was to create a building that would ‘achieve sustainability and teach stewardship of the environment’ as well as be ‘filled with light and integrated with the natural beauty surrounding it.’” Among the many sustainable strategies employed, the school features a highly efficient building envelope, including triple-pane windows. Architects say the building is designed to accommodate a 900Kw solar array, which would generate all of the energy required to run mechanical systems, lighting and power.
The building itself is designed to be a comfortable, welcoming place for students, faculty and the community. Natural and recycled materials are used throughout the school. Because research has shown that daylighting and outside views help stimulate learning, the spaces are engulfed with daylight. Guardian SunGuard SuperNeutral 68, which was used on the façade, creates a connection from the inside to the outside and the daylighting continues deep into the interior with movable glass walls between classrooms and shared learning areas.
Energy savings is the critical part of the building envelope and the result is significant. According to lead architect Tim Jewett, “The Washington State Sustainability Schools protocol mandates that schools have to meet energy savings based on LEED Silver. We more than exceeded that mandate. We are at the Gold, if not Platinum, level of that metric.”
The Energy Use Index (EUI) design-to-code minimum is 45 and Valley View Middle School came in at 18 EUI. “The glass system was a significant part of that,” says Jewett. “The glazing allowed us to not only meet the new energy codes in place during the design and build phase, but also achieve the new, more stringent codes that came out in July of this year.”
Jewett and team specified triple-glazed insulating glass units composed of three lites of clear 6-mm units with Guardian SunGuard SuperNeutral 68 on the number-two and number-five surfaces.
According to the architects, “The line between exterior and interior is blurred through expansive walls of glass, creating a connection to the environment and inviting the natural landscape inside … Glazing on one side of the library connects it to the commons; the glazing is inscribed with inspirational messaging derived from the educational specifications.”