Your Guide To
Straw Bale Building

In general, yes. A straw bale wall is roughly three times as efficient as conventional framing. Over the life of a typical thirty-year mortgage, this superior insulation can reduce energy costs by up to 75%, saving money and vital natural resources.

As with any building, details and the quality of craftsmanship matters and heavily influences the energy efficiency of the structures’ performance.

No. Canadian and U.S. materials laboratories have found that: “The straw bale/mortar structure wall has proven to be exceptionally resistant to fire.”

In these tests, the flames took more than two hours to penetrate the plastered bale walls. Conventional framing built to commercial standards took only 30 minutes to one hour to burn.

Due to their tight compaction, bales contain very little oxygen and thus resist combustion. It’s like trying to burn a phone book.

Loose straw, however, is a fire risk and during construction loose straw should be cleaned from the job site daily. Straw bale walls should be plastered as quickly as possible in the construction process to provide their tested fire resistance performance levels.

Pests are more of an imagined concern than a real threat. Once the walls are properly plastered or sided, there is no way for bugs or rodents to get into the bales other than to gnaw through 1 1/2”s of plaster.

If pests were to get inside the straw bale walls, they would find it almost impossible to move in the densely packed bales.

Termites and other pests pose more of a problem to conventional construction than they do to straw bale structures.

Again, as with any type of home construction, craftsmanship and attention to detail matter for long-term performance!

Moisture concerns can be handled with proper design and construction methods. So long as the bales are installed when dry (moisture content of 14% or less) and are properly sealed within the plaster and protected from water infiltration, they will perform well.

The adopted International Residential Code, Straw Bale Structures Appendix, has standards in place to accommodate this design and type of construction.

Even if a building is heavily rained on, it will be fine as long as it is allowed to dry out. Problems arise when high moisture levels above 20%) are sustained for long periods of time.

Bale homes were built in the 1800s and still exist in Nebraska and Europe. Straw bale homes have consistently withstood severe weather and wind in Wyoming and major earthquakes in California.

Many architects and engineers consider straw bales to be the ideal “seismic-resistant” building material. In wind tests, bale structures see no movement in a sustained 75 mph gale and only 1/16 inch movement with 100 mph gusts.

The best way to learn the art of straw bale construction is by taking a hands-on workshop. We offer 7-day hands-on workshops in several locations each year. These events are not only highly instructional, they are also extremely fun and often a life changing experience for those in attendance.  You can find the list of current workshops here. We cover all aspects of straw bale construction, from foundation tips to plastering and everything in between.

If you cannot take time off work and attend, consider purchasing one of our instructional on-demand courses, or joining us at one of our virtually held Workshops (announced periodically and held when our hands-on workshop travel schedule allows!)  

Finally, stay informed. The field of Straw Bale construction changes rapidly. To stay up to date make sure you are subscribed to our free community Straw eNews — we always share the best with our community first!