The Economist writes that straw buildings may be making a comeback, even if use of the material breaks local building codes. Straw may be an ideal building material for some types of buildings– it can be embedded with other materials to create adobe or stucco. It’s a great insulator. It’s often a waste material so can be recycled for low-cost. Additionally, straw buildings are highly earthquake-resistent because the material is inherently flexible and absorbs seismic energy better than steel, brick or glass.
In some areas, the benefits of using straw may not be realized because local building officials prevent its use. The Economist points to Californian officials who recently tried to dump heavy fines on Warren Brush, owner of a non-profit farm, for building straw-bale buildings on his property. “The problem is that California’s building codes make no provision for the use of straw. And Mr Brush has many defenders—among them several university scientists and David Eisenberg, the chairman of the United States’ Green Building Council’s code committee.”
Perhaps with all the support from the USGBC, more local officials will see the utility of making low-cost earthquake-resistant material widespread. The Economist writes that straw has beaten other materials in earthquake tests. “A year ago, a test conducted at the University of Nevada’s large-scale structures laboratory showed that straw-bale constructions could withstand twice the amount of ground motion recorded in the Northridge earthquake that hit Los Angeles in 1994.”
It’s the combination of materials that make straw buildings highly resilient. Straw building begin with a foundation of gravel contained in plastic bags covered with soil mortar. ”The walls are made of tightly packed straw bales held together with bamboo pins and lined with fishing nets. These are then coated with a clay-based plaster. Aesthetically, the final product is similar to stucco or adobe.”
Complicated work can also be done with the material. One structural engineer was able to create a two-story, three bedroom house with the straw mix. Additionally, in areas where there aren’t rules against using straw, there’s been a growth in projects, including a new post office in suburban Albuquerque and a Quaker school in Maryland.
Also, check out a new book on Shigeru Ban’s Paper Architecture. Ban has also faced a range of permit challenges, but has created stable, sustainable large-scale buildings out of paper.
Image credit: HOK / Inhabitat