The Living Roof: The lighter colored stone at the edges is for drainage. The soil medium is 8 inches thick and contains 25% organic matter. The straw mat is for surface soil retention. The waffle like layer is on top of the base rubber seal. The silt filter fabric is on top of the waffle to allow drainage. The roof is planted with a combination of native grasses and wildflowers to mimic the adjacent prairie restoration. The living roof reduces storm water runoff, insulates the building, and provides habitat for birds and insects.
Straw Bale Walls: Wheat straw (the stem of the wheat plant) is an agricultural waste product and readily available in Michigan.The straw in the Willows walls is from the Lee and Rebecca Crosby Farm in Caro, Michigan. The straw bales are stacked on edge like bricks and sewn with bale twine to the bamboo pins on the inside of the wall. The bamboo used here was grown in Cleveland, Ohio. The edge sand seams between the bales are mudded first to help the wall become more rigid and prepped for spraying the earthen plaster. The earthen plaster is made with lime and local clay, local sand, and water. Once the first coat of plaster dries a second finish coat is applied by hand. We used two kinds of interior finish plaster. The earthen plaster is made with only local clay, local sand, and water. The lime plaster is lime, local sand and iron oxide(a natural non-toxic yellow dye). Our straw bale wall systems were built by the Fox Natural Building Co. Chris Fox and his crew have pioneered this particular type of wall system. Stacking the bales on edge, the bamboo pins, the flashing detail, and the locally sourced earthen plasters are all innovations that better suit the temperature and moisture conditions of the Great Lakes region. Learn more at www.foxnaturalbuilding.com
Truth windows are a common architectural feature in Straw bale buildings. Truth windows show the "true nature" of the wall system. They are beautiful and serve as an interpretive tool.
Solar Electricity: We have a 3 kw solar photo voltaic array on the south roof. We are using a Michigan made Unisolar product which is laminated to the metal roof with an adhesive before the steel roof was secured. The wires from this pv laminate connect to the building through the ridge vent.
Passive Solar: The Willows is oriented so that the long side of its trapezoidal shape is facing south to maximize sunlight exposure. Light travels through the glass and changes to heat energy which is absorbed by the trombe wall (mass wall). The 10 inch thick trombe wall consists of black copper laminate, cement block, and field stone which transfer heat to the inside of the building. The four windows in the middle are operable for fresh air and a generous portion of daylight. On sunny, below freezing, winter days, this room will regularly gain 5 degrees with no moving parts.
Greenhouse: This room also is on the south side and functions the same as the trombe wall described above.
Day Lighting: This design element conserves electricity and provides a higher quality light and a healthier learning environment. Check out our solar tubes! 1 square foot of skylight provides the same light as 9 square feet of wall window.