Building with Straw Bales

While load-bearing bale walls are the most efficient when it comes to resource use, there are several other construction methods that incorporate straw bales into wall systems, with less opposition from building officials. Post-and-beam and pole-barn type buildings are using bales as in-fill insulation. A system of bales reinforced with a mortar matrix was built and extensively tested by the Canadian Mortgage and Housing Corporation, and Pliny Fisk III of Austin, Texas has developed a system for reinforcing bale walls with 1x4 ladder trusses. Finally, bales have been used as retrofit insulation for existing buildings. Most of these methods are still new enough that every new building offers modifications and improvements to the technique. The simplest, and most elegant system of load-bearing straw-bale walls, however, dates back to the 1880s in Nebraska (it is often called "Nebraska style"); some of these houses from as early as 1903 still stand in good condition.

Straw-bale construction has several important advantages over conventional construction. Insulation values are estimated at R-35 (for 18” bales) to R-50 (23” bales), ideal for climates with extreme hot and/or cold temperatures. In Nebraska-style construction, the bales are stacked and pinned together, wrapped with chicken wire or metal lathe, and stuccoed (or plastered), inside and out. The low materials cost and ease of assembly with unskilled labor make bale construction especially attractive for owner/builders.