Living Learning Center
What if every single act of design and construction made the world a better place? That’s the fundamental question posed by the International Living Building Institute, which created a new building standard that seeks to promote true sustainability in the world’s built environment.
When the leaders of Washington University’s Tyson Research Center in Eureka started planning to expand their facility, they wanted a new building that was “over the top green.” John Chase, director of the facility, found out about the Living Building Challenge, and decided that this was the certification they wanted to pursue.
The Living Building Challenge uses a flower to symbolize sustainable structures, where the building becomes an extension of the environment in which it is placed. The LBC calls for each building to produce all of its own energy from renewable resources, and capture and treat all of its own water and waste. This involves efficiency and conservation, but the standard also includes beauty in the building design. The ILBI uses the petals of a flower to represent the primary facets of sustainable building, including site selection, water, energy, health, materials, equity, and beauty. This standard is more stringent that LEED certification (the US Green Building Council’s Leadership in Energy and Environmental Design standard), with mandatory requirements that form an “all or nothing” certification.
I had the chance to tour Tyson’s Living Learning Center on a recent USGBC outing. Kevin Smith, Associate Director of the Center, welcomed a maximum capacity crowd to talk about the features of the building. It took two months to design and five months to build – an incredible feat given the unique challenges faced in building such a facility. Dan Hellmuth, principal of the architectural firm Hellmuth + Bicknese who brought the idea to the Tyson leaders, directed a team of people with complementary areas of expertise to design the building within a budget that was tightened in the final weeks of the design process. In the end, they created a model for sustainability which continues to receive praise and recognition.
Net Zero Energy
In order to comply with the net-zero energy challenge, the building envelope had to be very well insulated and sealed to minimize heat transfer. The building’s exterior was framed with 2 x 6 inch boards, and the insulation used resulted in an R30 rating, which is significantly higher than typical buildings. Silicone caulk ensured a tight seal around all openings through the structure, and double-pane windows were installed so they can be opened for fresh air ventilation when weather permits.
Because the building’s exterior is so well insulated and sealed, the building’s heating and cooling system doesn’t use much energy. The ground-source geothermal HVAC system that was originally designed had to be cut due to budget constraints, so a high-efficiency air-source heat pump was used instead. All of the lighting used in the building is either compact florescent (CFL) or LED. There is little demand for hot water, so an electric-powered tankless water heater is used.
To generate the energy needs of the all-electric facility, a 20 kW solar PV array was installed on the south-facing roof of the building. As the building managers studied the energy use, they decided to supplement this with a two ground-mounted arrays that are designed to track the sun across the sky during the day to maximize the energy production. The combined system overproduces in the summertime, with the excess energy flowing out onto the grid. In the winter months, any additional required energy is pulled from the grid as needed.
Net Zero Water
The other challenge was to collect and treat all of the water used on site, with zero waste. To do that, water is collected from the standing seam metal roof into a 3,000 gallon cistern buried under the ground. First, leaves and other natural debris are captured in a downspout clean-out. The cistern water is then appropriately filtered for use in non-potable applications, like cleaning outdoor plants. To keep water from stagnating in the storage tank, the water is recirculated through system. For potable (drinkable) water, the cistern water is run through multi-stage filtering system to remove particulate matter. Finally, to remove any remaining bacteria, the water passes through an ultraviolet filter before making its way to the tap.
Compostable toilets are similar to the all-too-common “porta-potties” found at outdoor events, except without the foul odor. The Clivus Multrum toilets use wood chips and water to naturally break down human waste. The wood chips act as a bulking material to keep the waste aerated, which is essential to the breakdown process. This provides oxygen to the aerobic bacteria, which ultimately do all the work. They also added red worms to help with the aeration and to help break down the organic matter into black water that can ultimately be used as fertilizer. This is a key factor in attaining compliance with the zero waste standard of the LBC.
A rain garden captures any additional runoff from the rest of the building, and the grey waste water from sink drains is captured and dispensed into a leaching field on the north side of the building. The small parking lot and sidewalk are made of pervious concrete to absorb the rain water that falls onto the paved surface.
In addition to attaining net-zero use of energy and water, the building designers had to refrain from using a number of commonly used building materials that are toxic. This includes polyvinyl chloride (PVC), which is a standard for plumbing and wiring, and a number of other foams and plastic compounds. Of course, heavy metals like lead, mercury and cadmium are also forbidden, as are other known carcinogens like asbestos, formaldehyde and arsenic. Chlorofluorocarbons (CFC’s) and similar refrigerant gases are also on the Red List of banned materials. While it seems obvious that these toxic substances would be avoided, they continue to be utilized in the building industry on a regular basis.
For more information on the Living Building Challenge, check out the narrated online presentation. This promises to provide a whole new level of sustainability in a world that is currently well out of balance.
This was published as a two-part series in the Going Green section of Spirit Seeker magazine.