Green Legacy

The greenest building in the United States may now stand in Wisconsin, on land reclaimed by one of the nation’s groundbreaking environmentalists. The Aldo Leopold Legacy Center received LEED Platinum certification and one of the highest rankings yet awarded from the U.S. Green Building Council (USGBC). The award was presented on Oct. 18 at the center in Baraboo, Wis.

Built to the highest standards of energy efficiency and sustainability, the center employs some of the most innovative materials and systems ever integrated in commercial construction in the United States. The project received 61 of 61 points submitted (out of a possible 69), which is the highest point total yet recorded by the USGBC LEED rating system.

The Aldo Leopold Legacy Center is the first net zero energy building in Wisconsin and the first carbon neutral building certified by LEED. To achieve net zero energy performance, annual building energy demand is matched by the output of clean, renewable energy systems on site. The center will produce approximately 115 percent of annual building energy needs.

The 12,000-square-foot Legacy Center was completed in spring of 2007 and serves as a visitor center and headquarters for the Aldo Leopold Foundation. It was designed by The Kubala Washatko Architects Inc.; construction management and LEED consultation were provided by The Boldt Co.

"Aldo Leopold cared deeply about people and land, and this building carries his values and principles into the 21st Century. As concern grows about our future and life on this planet we call home, the Leopold Legacy Center demonstrates the positive contributions we can make to both the built and the natural landscape," says Buddy Huffaker, executive director of the Aldo Leopold Foundation. A renowned writer, forester and ecologist, Leopold died in 1948, but his book A Sand County Almanac has sold over 2 million copies and can be found on the shelves of many of today’s most innovative green leaders. In the 1930s and 40s, the Leopold family planted thousands of trees to protect the farm’s eroding soil, to improve wildlife habitat, and to demonstrate care and respect for the land. The experiment continues today on the Leopold Memorial Reserve.

"As architects, we took inspiration from[a cottage on the property], but we did not seek to copy it," says Allen Washatko, principal of The Kubala Washatko Architects Inc. "Beyond mere technical solutions, we wanted to capture a sense of the deep ecological and aesthetic spirit of Aldo Leopold and his family."

When the project team set a goal to create a building that produced as much energy as it consumed, architects from The Kubala Washatko Architects Inc. looked to design influences from Europe. High energy costs overseas have driven that market to use techniques and systems not in the mainstream in the U.S. "We wanted to be the team that took the huge step to show how extreme energy efficiency worked in a commercial setting and to show that it is relatively easy to install," says Joel Krueger, project manager from The Kubala Washatko Architects Inc.

Individuals brought varied areas of expertise to the project. One team member was a University of Wisconsin—Milwaukee School of Architecture faculty member who designed extensive and sophisticated computer energy modeling. Associate Professor Michael Utzinger used a hybrid modeling system which allowed the team to isolate individual energy components in the building and assess each system’s impact on the whole building. In all instances individual systems and total building energy modeling were measured against typical buildings constructed according to state code requirements.

"Based on our experience relative to other LEED buildings, we’re confident that the Legacy Center will be in the range of operating 75-80 percent better than code and we’ll achieve a net-zero energy building," Utzinger says.

Energy usage assumptions are based on the track record Boldt, the architects and other partners have with LEED construction. "This team isn’t cutting their teeth on the project, but pushing the envelope based on their experience," Utzinger says.

Boldt credits the Leopold Foundation for being the driving force for this project. "The owners had to be on board and agree to this level of sustainability," says Theresa Lehman, Boldt’s LEED consultant. "Plans called for installing systems that required an initial up-front investment, but will greatly reduce energy costs and the impact on the environment," she says.

The building is literally green from the ground up. Part of Leopold’s legacy is the result of his mission to return his 80 acres from worn-out farmland to a mosaic of pine forest, prairie grassland, and other ecosystems native to Wisconsin which he and his family did by replanting native species. In winter of 2006, the trees were carefully harvested from the Leopold forest and used to create the columns and beams that hold up the Legacy Center.

"The use of Leopold wood is the most visible, and perhaps most symbolic, of the project team’s efforts to design a building within the resources—sun, water, and earth—available on the site," says Tom Kubala of The Kubala Washatko Architects, Inc.

From the inside the pitched roof will be tongue and groove paneling—all made from Aldo Leopold’s trees. "When you look up, you’ll see Leopold overhead," says Gregg Tucek, Boldt project manager.

The energy system is the most unusual component in the building which uses modeling the Boldt team had never encountered before. "We have a lot of experience in LEED certified construction," says Tucek, "but from day one we were breaking new ground on this project." The building uses an innovative approach to energy management to create a net zero energy building. The building’s performance has so far matched the modeling, which projects that the building will actually produce more energy than is consumed on an annual basis. This landmark net zero performance is rooted in fairly old-fashioned ideas—like maximizing insulation and capturing daylight and natural breezes—as well as advanced technologies that harvest the huge energy resources of the sun and the earth.

The site uses a roof-mounted photovoltaic solar array projected to produce as much electricity as is typically used by six households in one year or 110 percent of the Legacy Center’s expected electricity use. When more electricity is being produced than is consumed, the surplus is sold to the local utility. In June and July 2007, the Leopold Foundation sold 8,948 kWh and purchased 1,920—a 7,000 kWh surplus.

"What I like most is it’s the most simple, pure way of producing energy as a system," says architect Joel Krueger. What starts with the sun proved an engineering challenge for construction.

The building incorporates a geothermal heat exchanger used in the water-based heating system. Wells were drilled deep into the ground and a closed loop of piping went in below the frost line. The system uses the earth’s stable temperature to pre-heat or pre-cool water relative to the air temperature. "The ground is always about 55 degrees Fahrenheit, so in the summer air brought into the building will already be cooler than the surrounding air and in the winter it will already be warmed," Tucek says. Highly-efficient heat exchangers multiply this temperature gradient to further heat or cool the fluid that runs through the radiant floor system.

In many ways the Legacy Center is the ultimate "smart building." The instrumentation in the building will not only collect data on the innovative systems, but it will monitor how fast the air moves through the earth tubes or the temperature of the water in the in-floor heating system to keep the building at a net-zero level.

"It’s almost like a living laboratory," Tucek says. "Some buildings integrate a portion of green elements, but in this project we’re seeing Leopold’s vision come to life in every facet of design and construction."

The project was led by The Kubala-Washatko Architects, Cedarburg, Wis. The Boldt Co. provided construction management and LEED consultation for the project. Boldt provides strategic planning, sustainable consulting, and design management and construction solution services to customers in industrial, institutional and commercial markets nationwide. The Kubala-Washatko Architects provides planning, architectural design and sustainability consulting for projects in the United States and internationally.