Going Green On The Rooftop!
By Laura Gibbs-Green
Visitors to Nicholas Conservatory & Gardens in Rockford, Ill., have been seeing plenty of green—not on the ground—but on the roof. Construction of a 4,300-square-foot green-roof garden at the conservatory began in July 2012 and was completed in August 2012. A viewing deck, which can accommodate 20 to 30 people, opened to the public during select hours beginning in the latter month. The green roof is the first project of its kind in the park district.
The LiveRoof hybrid green-roof system from LiveRoof LLC (Spring Lake, Mich.) was selected for the project. Christiansen Roofing Inc. of Rockford installed the roof, which was made possible by the financial support of Aqua-Aerobic Systems Inc. (Loves Park, Ill.).
“The green roof decreases storm water runoff, reduces energy use by insulating the rooftop, and extends the service life of the building’s structural roof by shielding it,” says Ruth Miller, manager of the facility. “In addition, [it] allows us to enhance educational opportunities by teaching visitors about sustainability during select times when the green roof is available for tours.” The conservatory is a LEED-certified facility, and the new roof will increase the building’s LEED points.
Situated along the banks of the Rock River, Nicholas Conservatory & Gardens brings the tropics to the Midwest. The facility is the third-largest conservatory in Illinois, with a total of 22,000 square feet. A tropical setting includes an 11,000-square-foot plant-exhibition area complete with water features, seating areas, and sculptures.
For more information, visit www.rockfordparkdistrict.org/ncg.
Effective storm-water management—Extensive green roofs can reduce the volume and velocity of storm-water runoff into sewer systems by 50 to 90 percent.
Improved water quality—Green roofs filter pollutants out of rainwater, and act as buffers against acid rain.
Longer roof life—Green roofs serve as shields to prevent UV radiation and temperature extremes from degrading roof components.
Energy conservation—By shading and insulating the rooftop, green roofs keep rooftop temperatures in line with ambient air temperatures, thereby reducing peak energy demand, especially for air conditioning in summer. That decreases facility operating costs.
Energy efficiency—Green roofs boost the efficiency of air-conditioning units and solar panels on the rooftop. This also decreases building costs.
Urban heat-island effect mitigation—Plants release oxygen and evaporate water through photosynthesis. That makes a green roof function like a natural evaporative cooling system that moderates temperatures, not only on the rooftop but at street level as well.
Improved air quality—As with all plants, green roof plants sequester carbon dioxide from the air and release oxygen. Every 1,000 square feet of an extensive green roof can capture over 80 pounds of CO2 annually. Green roofs also naturally filter harmful particulates and air pollutants. Every 1,000 square feet of an extensive green roof can filter about 400 pounds of dust and smog particles per year.
Green building credits—Green roofs can contribute to U.S. Green Building Council LEED credits in potentially multiple categories.