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Historical use Straw has had a central place in construction for most of human history. Composed of the same basic materials as wood, it's quite strong and inert, provided is doesn't stay moist, and its hollow tube configuration gives it good insulating properties as well. Roofs thatched with straw were traditional across northern Europe, Russia, and in the northern portions of eastern Asia, including Japan. The tatami floor mats of Japan are flat straw bundles with woven grass faces and cloth edges. In cold weather the tipis of North America were insulated with loose straw between the inner liner and the outer cover. Mixtures of straw and mud comprise the second major traditional use of straw, and these mixtures can be found in a wide range of earth-to-straw ratios: Adobe and cob use straw as tensile reinforcement for earth mixes, and at the other end of the spectrum lichteum (literally “light clay” in German) uses straw as the principal element with clay as a coating and binder. In between these two extremes are a whole range of earth plasters that incorporate chopped straw as an element. Cow dung, for instance, is one of the world’s most common plasters, and is in essence composed of straw that has been "chopped" (and otherwise processed) by the cow. The natural building movement, then, is rediscovering a building material that has been around forever. We just "forgot" about it for a few generations during industrialization. Earling Baling During the mechanization of American agriculture, the need to simplify the storage and transport of hay and straw led to the development of the mechanical baler in the mid-1800s. That the large lightweight blocks produced by these machines were quickly seen as a potential building material is indicated by the numerous U.S. patents issued for building with bales dating from this period.1 The use of bales in walls remained an exploratory realm by isolated individuals, however, except for one historic circumstance that favored bale construction sufficiently to create a history. When the sand hills of western Nebraska were opened to homesteading in the mid 19th century, importing lumber to the area was very expensive, and unlike most of the great plains, the thin sod that overlaid these sand dunes was too fragile for building sod cabins. Horse powered bailers were available, so between 1896 and 1945 some 70 bale buildings were constructed in this region, of which 13 were known to still exist in 1993. When these historic structures have been examined by current straw bale builders, they appear to be in sound condition. While visiting the Faun Lake Ranch in Nebraska, whose straw bale structures date from 1928, I was able to withdraw some straws through a crack in the interior plaster of the bunkhouse. They were still flexible, still strong in tension, indistinguishable, in fact, from what I pull from a bale harvested this year. 
In spite of its obvious advantages, straw bale construction was forgotten after the homesteading period in Nebraska except insofar as individuals reinvented it on their own. Luis Gagne in Quebec, Tapani Marjamaa in Finland, and Dr. Burritt in Alabama are all examples of this recurrent phenomenon of individuals developing bale building techniques entirely on their own. |
