Under the gravel parking area, 48 geothermal wells go 300 feet into the ground to take advantage of the earth's constant temperature (about 54 degrees) to heat and cool the facility.
Natural ventilation takes advantage of the Bay's breezes to cool the building without relying solely on air conditioning. When sensors determine that the outdoor climate is suitable, the mechanical system shuts down, motor-operated dormer windows open to allow warm air to escape and naturally cool the building. and "open window" signs signal staff that they may open their manually operable windows to allow cooler breezes into the building.
To reduce the need for electricity, the building is situated on the site to receive maximum southern exposure for natural light and warmth and to take advantage of prevailing winds for natural ventilation. Using the sun's heat in the winter and natural ventilation during many months of the year, the building's heating and cooling systems run only about two-thirds of the year.
Natural daylight from the southern window wall illuminates the entire building, substantially lessening what is usually an office's most expensive energy cost. Outdoor sun-shade trellises oriented to provide shade in the summer prevent most heat from entering the building. Also, an open office layout allows daylight to flood the building with natural light, minimizing dependence on costly artificial light. The open office layout also provides more efficient heating and cooling.
Extremely efficient structural insulated panels (SIPs) used for the building's walls and ceilings reduce energy demands and costs. The panels have a foam core that is four to eight inches thick (depending upong the needed "R" value for insulation). These panels use considerably less wood than conventional framing, and have a very high insulation value. Use of SIP also reduced construction cost because traditional framing and installation of insulation and interior walls was not required.
Rooftop cisterns capture rainwater for use in irrigation, fire suppression, hand-washing, mop sinks, gear washing, and laundry. Re-using rainwater reduces the need to draw from groundwater wells or municipal water systems, and decreases runoff to the adjacent Bay and Black Walnut Creek. Water consumption at the Merrill Center is 90 percent less than a conventional building.
Our 12 composting toilets and urinals use just one gallon of water a day. Human waste is composted naturally to produce topsoil for our landscaping. This saves water and reduces the load on sewage treatment plants that contribute nutrient pollution to the Bay. It also reduces maintenance and eliminates damage due to toilet backups and overflows.
Recycled and Renewable Materials
We used numerous recycled material to construct the building. Cork flooring and wall panels come from cork oak trees. Cork, which is harvested without killing the tree, regenerates in seven to nine years. Bamboo, used for the beautiful hardwood flooring on stairs and in the lobby, can be harvested every three to five years and replenishes itself naturally. Posts, beams, and trusses are made from Parallam (strand lumber made from fast grown wood). Galvalume (recycled steel panels) is used for the siding and roofing. Other wood in this building (decks, plywood, and all dimensional wood) is either certified by the Forest Stewardship council (FSC) or drawn from sustainably managed forests. FSC forests are managed to conserve biological diversity, protect endangered species and their habitats, and encourage forest regeneration and succession. The ceiling tiles are made from 78 percent recycled mineral wood and cellulose fiber, the rebars are made from 95 percent recycled steel, and the particleboard is 100 percent recycled and recovered wood fiber. Concrete from the building site was broken up and used for the current road bed. Deconstruction of the site's former buildings was carefully managed for recycling of materials.
Fewer Chemical Vapors
Indoor air quality is enhanced by choosing building materials with no or very low Volatile Organic Compounds (VOCs), such as natural linoleum, cork, and bamboo, and paints and adhesives. These reduce chemical vapors and create a healthy working environment.
CBF has restored onsite habitat for wildlife by planting a diversity of native trees and shrubs, underwater grasses, restoring wetlands and meadows, and creating a sanctuary oyster reef.
Stormwater passes through a bioretention stormwater treatment system in the form of manmade and natural wetlands to filter water before it enters the Bay or the adjacent Black Walnut Creek.
What Makes US Green
The first building to receive the U.S. Green Building Council's Platinum rating for Leadership in Energy and Environmental Design (LEED), CBF's Philip Merrill Environmental Center continues to win international acclaim as a model for energy efficiency, high performance, and water conservation. Take a look at the products and systems that earned us the title.