by John Shriver

Created on: August 06, 2008

There is an alternative to building with wood, straw bales. A straw bale house uses straw bales either as insulation or as the structural building block of the home. People may be surprised to learn that the early settlers, especially out on the plains where wood is scarce, turned to straw bales as a construction material. Straw is what is left after grain heads has been stripped from the stem. At some point in the 1890s, settlers started building homes, barns and schools with straw bales and a few are still standing today. The early ones weren't meant to be permanent but once someone started applying mud or plaster to the exterior, these early settlers found that the inside stayed cool in the summer and warm in the winter and was almost fire resistant due to the tightly compacted bales.

Each year 200 million tons of straw go unused, it's a by-product of growing crops and there is little use for it either within or outside the farming community. But with the increase of lumber prices, many homeowners are looking toward this alternative building material. Bales normally come in three sizes but the most frequently used is 16-17 inches high, 23-24 inches wide and 42-47 inches long with three strings or baling wire holding it together. The field baler tightly compresses the straw into the above dimensions, making it almost airtight and it is typically stored in a dry place before using. According to the few local building codes covering straw bale construction, the moisture content can't exceed 30 %.

With straw bale construction on the rise, farmers and ranchers have discovered a new market for what they once considered waste. They now store the bales in a dry place and wait for the customers to come to them, delivery is extra. In Colorado, straw bales are going for $105-$140 a ton, still cheaper than a pallet of wood 2x4s.

The straw bale walls can be either load bearing or non-load bearing (the roof supports are independent of the walls, this method is preferred). Once the supports are in place, it's a simple matter of stacking the bales between the supports, leaving the openings for doors and windows staking them together with wooden dowels and letting them settle before applying the exterior coating. Sprayed concrete or stucco has been used while others prefer the epoxy method, both will do. Once that has dried, all that's left is finishing the inside in any manner that suits the builder. The inside walls can also be plastered and paneling installed over it.

Once completed, the structure will exhibit an R rating from R-30 and up to R-45 and with concrete stucco, the rating will be higher. In addition to the high R rating, straw bale construction also achieves a high degree of fire resistance. And even after years of use, there have been no complaints of any bug or termite infestations. Most homeowners have seen a 75% reduction in their heating/cooling bills, making straw bales environmentally friendly. With the installation of a solar hot water heater, the gas/electric bill would be even lower.

Many communities across the Midwest and the lower states have had to adopt new building codes to address the rise in straw bale construction and are constantly adapting to the changes in this alternative building method. Austin, Texas recently became the fifth government body to adopt a straw bale construction building code. Many contractors have sprung up across the Midwest to embrace this new construction, at least new to them, and many offer an all-inclusive package for the homeowner. As construction prices continue to rise, more new home builders will turn to straw bale construction as a way to save thousands of dollars.

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