Straw-bale buildings can cut utility bills considerably.

Straw-bale buildings not only appeal to ones aesthetic side; these beautiful structures like the one at Willow Bend are practical examples of sustainable, cost-effective living. Straw-bale buildings are three to four times more energy-efficient than conventional construction. Straw is often burned as a waste product and puts more than twice as many pollutants in the air each year in California than all of the fossil fuel power plants. When you use straw instead of wood, you not only save energy but you also use a renewable resource instead of other less renewable materials. Often, these less-renewable materials can be toxic and require more energy to produce and transport.


Our passive solar, straw-bale building

In 2002, with the help of many wonderful community volunteers, Willow Bend realized its dream of building an environmental education center! The center’s design incorporates passive solar features that allow the sun to warm up the colored, scored, and grouted concrete floors. The building has a wood-frame construction with straw bale walls on the west, north, and east sides, and three trombe walls on the south. Trombe walls are 12-inch sand blocks filled with grout and mortared and painted black on the outside. The glass pane above the wall helps to trap heat, which is transferred to the interior of the building at night. Our ceilings feature blown-in fiberglass insulation. The result is an eco-friendly, low-cost building that functions as both a comfortable workplace and useful education facility.

Willow Bend visitors often comment on the comfort of the building. During the day, we only use natural light and the natural heat of the sun. Only on rare occasions do we need supplemental heat from a small wood stove — usually fewer than six times during the winter. Because of its straw bale construction, our building is not as drafty, making 65º here actually feel warmer than in a conventional home. The building has a very organic and soothing feel, making it an ideal place to work, meet, and teach. Many other organizations in Flagstaff use our building for meeting and workshop space.

Here’s how our building compares to conventional construction:

Walls Willow Bend R-33
Conventional R-12
Ceilings Willow Bend R-50
Conventional R-30 to R-38
Floors Willow Bend R-10
Conventional R-0

Passive solar design principles

Willow Bend is a beautiful example of a functional building that incorporates passive solar principles to use the sun’s natural energy while decreasing the impact of our office on the environment. These principles include:

Willow Bend uses these passive solar principles to heat the building without auxiliary heat. However, we do have a wood-burning stove in case the need arises. In the past, we have only needed to use the stove an average of six times each winter.