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During the spring 2002 semester, students and faculty from the two universities designed a resource-efficient, regionally appropriate literacy center for the Northern Cheyenne.

That summer, a group of 70 students, practitioners, faculty, and tribal members dedicated two weeks to stacking and stuccoing straw bales. This blitz-build was one in a series of projects sponsored by the American Indian Housing Initiative (AIHI).

Straw Bale Construction

Recent technical developments born of experiments in straw bale have led to sturdier buildings approved by building codes in many areas. The critical aspects of construction remain simple, however.

After a traditional foundation has been prepared, the bale walls are raised on a bed of gravel trapped between strips of treated lumber. Like bricks, the bales are staggered to avoid continuous joints, and wood frames are added to distribute the load at door and window openings.

As the wall rises, the bales are pinned together with rebar stakes and strapped together using heavy-duty package strapping to compress the bales. Once the walls are completed, a plywood box beam is laid on top to ensure equal distribution of the roof loads and equal compression of the walls.

The roof is then built, and metal lathe is attached to walls to reinforce the stucco. During a period of wall settlement, electrical and site work continue. When the compression ceases, three layers of stucco are applied to the walls, providing stiffness, protection from moisture, and a sublime exterior finish.

At this point, the major elements of the building are in place, and the remainder of construction is consistent with standard practices. According to PSU professor Scott Wing, one of the faculty advisors, "Two key performance questions that challenge straw-bale applications are the load-bearing capacity and insulating value of straw-bale walls."

Without hard data, the designers use conservative values in structural and energy modeling. For instance, they limit roof spans and make modest claims of energy savings. But this may change in the future because part of the course research, according to Wing, "focuses on the optimization of mechanical and thermal behavior of straw-bale wall systems and their compatibility with solar and wind energies."

Benefits of Straw Building

Nebraska-style straw bale construction costs roughly the same per area as conventional wood-frame construction. The use of volunteer labor for bale raising and stucco can significantly reduce costs, however, helping to make housing more affordable.

More importantly, straw bale buildings encourage a long-term conception of value that includes the calculations of cost savings from low maintenance expenses and superior energy efficiency.

In addition, when people work together to create buildings, the value of what is built expands beyond the realms of finance to include the values of community and cultural relationships. Such a building becomes a matter of the whole community's concern and the mutual interest forms natural bonds between people.

Building Community

AIHI began as a response to the ongoing housing crisis on many reservations. It is a joint effort of UW, PSU, and the Red Feather Development Group to restore a culture of self-sufficient housing in American Indian tribes.

Drawing on a pool of students studying architecture, sustainable development practices, landscape architecture, and engineering, AIHI provides the labor, technical knowledge, and financing necessary to build much-needed housing and community facilities.

In addition to serving immediate needs for families without adequate housing, the work provides a hands-on opportunity for teaching students and tribal members about sustainable building techniques. In the midst of building and learning, students and tribal members share experiences and learn about each other.

The social aspect of straw bale construction serves a crucial role in the American Indian Housing Initiative. The simplicity and democratic nature of construction allows the techniques to be passed on easily. This method of building encourages self-sufficiency and an understanding of what a community can achieve through shared labor. Like straw, these valuable resources abound on reservations and among students and need only to be harvested.

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UW Alumni: Yarrow Murphy, Bill Terry, Janey Terry, Kathleen Westby

Straw bale construction, as done for the Literacy Center at Chief Dull Knife College, is a social as well as technical exercise. Photo: AIHI Straw bales are pinned together with rebar stakes. Photo: AIHI A plywood box beam on top of the walls ensures equal distribution of roof loads and equal compression of the walls. Photo: AIHI Installing the roof trusses over the walls of straw. Photo: AIHI The straw bales are held together with heavy-duty package strapping and chicken wire. Photo: AIHI Applying the first layer of stucco is a community event. Photo: AIHI Traditional artists lay tile on interior walls. Photo: AIHI An interior straw-bale buttress. Photo: AIHI   Click on thumbnail images to view full-size pictures.