The Greenest Green House
The two-story, 20,000-square-foot Juliet Rice Wichman Botanical Research Center is Kauai’s first LEED-certified building. The certification given by the U.S. Green Building Council is the gold standard in green construction.
The $12 million concrete structure at the National Tropical Botanical Garden’s Kalaheo headquarters will hold a herbarium with 56,000 plant specimens (some endangered), a research library, a laboratory and research areas. With all the rare and important artifacts, the building needs to have a highly efficient air-conditioning system, but there are plenty of other sustainable features.
Although green building is a hot buzzword, “Designing responsibly is what it comes down to,” says Dean Sakamoto, lead architect on the project. This includes aligning the building north and south to protect from the harsh east and west sunlight, and minimizing the manmade footprint on the natural setting.
Active Roof: A 30 kilowatt-hour photovoltaic panel system built into the roofing membrane converts solar power into usable energy for the research center. Three light wells act as skylights and filter in indirect sunlight, minimizing the need for artificial light inside. The low slope roof channels rainwater to a secondary roof, where downspouts collect the water in a 25,000-gallon underground water catchment.
Hurricane Protection: An exposed concrete exoskeleton, which wraps around the perimeter of the building’s second floor, provides an additional structural support that can withstand Category 5 hurricane (155 mph-plus) winds. In addition, the frame blocks much of the sunlight from the windows in the library, cutting down air conditioning costs. Moreover, with 8 feet between the concrete perimeter and main structure, the frame also doubles as a catwalk, allowing staff easy access for cleaning and maintenance.
Local and recycled materials: The weather enclosure of the building is clad with reclaimed tropical hardwood from Southeast Asia. Local stones were used at the base of the building, and Kauai sand was used for aggregate in the reinforced concrete.