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Future Farmstead Program, Univ. of Georgia, Tifton, Ga.
Georgia-Pacific Gypsum’s DensGlass sheathing was used for the exterior of Atlanta’s National Center for Civil and Human Rights Museum.
Brian Wolfe, LEED AP BD+C, keeps tabs on all things green for HKS Architects. Wolfe explains that the path to net zero begins with knowing the space type, location and project code baselines. It’s also important to apply energy use intensity—energy being consumed per sq. ft.—to the parameters that are needed to be known. When it comes to envelope design, he sees window-to-wall ratio as the biggest challenge. “The market favors extensive amounts of glass,” he says. “This benefits views, but negatively impacts the energy savings. Finding the ‘happy medium’ is a team effort.” One option is determining the optimum balance between decreasing the window-to-wall ratio and installing daylight sensors. In addition, knowing if the glazing system will be operable or not can potentially allow for strategies such as natural ventilation, which can reduce peak demand of the mechanical systems. Holistic thinking is crucial. "Each design option affects the other."
42 | 06.14 | NET ZERO BUILDINGS
The Future Farmstead Program at University of Georgia, is a 3,000-sq.ft., two-story structure in Tifton, Ga., that serves as a research facility dedicated to the sustainable production of food and energy.
Strong Curves The new National Center for Civil and Human Rights Museum in downtown Atlanta is cradled between two powerful, convex-curved walls. The exteriors of each flowing wall serve as a terracotta rain screen envelope to ensure energyefficiency and sustainability of the 42,000-sq.-ft, three-story facility, and DensGlass sheathing from Georgia-Pacific Gypsum was chosen for exterior sheathing material. “We needed a product with the dimensional stability and flexibility to work with compound curves,” said Michael Katzin, vice president for architecture, senior project manager and principle at HOK Atlanta, the architect of record for the project. DensGlass’ flexural strength is approximately the same in both directions, meaning it can be installed either vertically or horizontally without sacrificing wall strength between studs, and the panels also protect and help stabilize structural framing—an important consideration for the curved walls of the center.
Also being the residence for the project’s graduate students, it is also a test lab for using sustainable building materials. One of these is the Home Slicker rainscreen from Benjamin Obdyke.
Employing a vegetated double skin for passive cooling, RMA Architect's design of this office in Hyderbad, India is up for a 2014 Zumtobel Group Award. Its inner facade has operable windows for natural ventilation; the outer facade's trellis is covered with vegetation that not only helps with IAQ, but allows for a dynamic facade as it changes with the seasons.
The system creates an air space between the back of the cladding and the face of the waterresistance barrier, which reduces the forces that draw water into the wall assembly and drains excess moisture via the air space. This helps prevent deterioration and mold that can result from skin materials that don't account for rainwater drainage.
Highlighting the Path Toward Net Zero Building Design.