| Sustainability in the
National Parks--Part II, Yellowstone
Of the many national parks I visited this summer, perhaps the one most
familiar to me is Yellowstone--now the destination of more than 3
million visitors annually (nearly 25,000 visitors a day in the summer
season). I had spent many childhood summers hiking to Yellowstone’s
geysers and fishing in the park’s lakes and streams. It had been almost two decades since I had last visited the park, but I wasn’t surprised at the ecological-savvy changes that I had read about--bears no longer beg along the roads (begging bears is a strong childhood memory), wolves (not a sight in my youth) now can be glimpsed in Lamar Valley and recycling and sustainability efforts have reached levels not even dreamed of at age 10 when I would pick up trash I found along Yellowstone's trails. To me, the real revelation was that in December 2004 Yellowstone had received LEED certification for its two new employee homes, making them the first LEED-certified concessions buildings in any national park. Completed in July 2004, the 2,000-square-foot buildings are home to employees of Xanterra Parks & Resorts (Yellowstone’s concessionaire), including Jim Hanna, environmental affairs director for Xanterra in Yellowstone. Built by Martel Construction, the three-story houses are located at Yellowstone’s northwest gate just north of Mammoth Hot Springs in the town of Gardiner, Mon. The homes are intended to be the benchmark for other green, energy-efficient construction developments within Yellowstone and other national parks.
I wasn’t the only one impressed by this latest Yellowstone development. This year, the National Park Service presented its 2005 Environmental Achievement Award, which acknowledges exceptional achievements and contributions in a broad range of environmental areas including sustainable design/green building, to Yellowstone National Park and Xanterra Parks & Resorts for the environmentally sensitive design and construction of the two Xanterra employee housing units. It is expected that the sustainable homes' special construction and passive solar design will save up to 70 percent in energy costs, compared to conventional construction. Constructing to LEED In its quest for LEED certification, Xanterra worked with park service personnel and had on its preplanning team a number of LEED-accredited professionals. The team included a LEED consultant, architects, and civil, electrical, mechanical and structural engineers. The team determined that sustainable energy strategies for the houses should include a photovoltaic energy system, passive solar heating, a super-insulated envelope, construction waste recycling and extremely efficient plumbing fixtures. A previous industrial site that contained a fuel transfer facility was chosen as the site for the buildings. The site required the removal of old concrete slabs, tin sheds, rusted fuel tanks, rebar, leaking oil drums, solid waste, noxious weeds and oil-contaminated soils. When designing the home, the architects (Overland Partners Architects and StudioForma Architects) were told to make the homes at least 40 percent more energy-efficient than a standard home. To create a super-insulated envelope, they chose insulating concrete forms--Quad-Lock panels from Quad-Lock Concrete Building Solutions. Since the building site is located on a slope, the lower level of the houses is partially below grade. The houses’ foundations feature 8-inch-thick concrete and 6-inch-thick insulating concrete form walls with 2-inch-thick interior foam and 4-inch-thick exterior foam. The walls offer R38-rated insulation versus R14 found in traditional stud and fiberglass insulation walls. More than 20 percent of the LEED certification points used in the application process was a direct result of using Quad-Lock materials. Quad-Lock helped allocate points to Materials & Resources, Construction Waste Management, Local & Regional Materials and Energy & Atmosphere. The roof system was constructed of structural insulated roof panels. Using a sandwich of oriented strand board (OSB) and 12-inch foam insulation, the roofs offer R60-rated insulation versus the standard R30. In addition, the panels allow a large interior space that provides for cathedral ceilings on the third floor. Letting the Sun In Each house has a photovoltaic electric system on the roof, which generates 10 percent to 40 percent of the building’s electricity demand. In addition, the homes incorporate passive solar heat and thermal heat sinks in concrete floors and walls. The concrete slab floors of the houses are 12 inches thick in the main level sunrooms, 6 inches thick in the kitchens and 2 inches thick in the upper level open spaces. Combined with southern orientations, special window glazing allows greater ultraviolet heat transfer. An exposed concrete wall between the sunrooms and kitchens and the slab floors absorb the sun’s heat and transfer it throughout the homes during the winter when the sun is low in the sky. Each building also includes a high-efficiency propane boiler that provides hydronic heat through the baseboards for the entire house. (There are three heating zones, each piped to a different floor.) As the boiler heats the hydronic baseboard heaters, the hot water tanks are heated by re-circulating boiler water. The boiler is 93 percent efficient versus 80 percent for standard boilers, and the hot water tanks are 93 percent efficient compared to 54 percent for standard tanks. Additional sustainable building and energy efficient features of the houses include: --Air-to-air heat exchanger. Essential for highly insulated homes, the air exchanger draws warm, “dirty” air from the bathrooms and cold “clean” air from outside, exchanging heat energy before circulating it throughout the houses. --Energy Star appliances and water-saving fixtures. The Maytag Neptune stack washer/dryer and the Frigidaire dishwasher, refrigerator and range all exceed federal Energy Star standards by 15 to 45 percent and reduce daily water consumption from 57 to 34 gallons on average. --100 percent compact fluorescent lighting. The lighting uses 70 percent less energy and lasts 10 to 13 times longer than incandescent bulbs. --Dual flush toilets. This system allows users to select either a 1.6-gallon or .8-gallon flush, saving thousands of gallons of water over the toilet’s lifetime. --Xeriscape landscaping. Plantings include nonirrigated, native and drought-resistant varieties. No potable water is used to irrigate the landscaping. A “Greener” Future Next on the agenda for sustainable building at Yellowstone? The Old Faithful Visitor Education Center (OFVEC), which is slated to be the first visitor center in the National Park system to earn the U.S. Green Building Council’s Silver LEED (Leadership in Energy and Environmental Design) certification. Some of the “green” features of the new center will include a design that allows for a reduced heated space during winter months and the use of certified wood and water conserving fixtures. In addition to helping visitors understand and appreciate Yellowstone’s hydrothermal features and volcanic activity, the new visitor’s center will also showcase the park’s commitment to environmental practices and sustainability. The project received a boost last fall when Toyota donated $1 million for the center and offered consultation from its building engineers regarding green building construction. (Toyota built its own Gold LEED certified building in 2003.) Toyota’s donation to the Yellowstone Park Foundation brought the total amount raised for the center to $14.6 million. Construction on the center could begin as early as spring 2006, following the planning and design process.
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