Straw bale walls pass earthquake test
August 31st, 2009Straw bale construction has attributes that often seem counterintuitive. Fire resistance for instance. Few people would have imagined that straw bales were class ‘A’ fire resistive construction just as few would have imagined that a plastered straw bale wall was a 2 hour fire wall. Others could be that it is rot resistant, highly insulative and structural. Yes, straw bales are structural and more than that they are able to withstand an earthquake much better than some popular modes of building. Being somewhat squishy, uh that is a straw bale technical term, they work much like a shock absorber rather than being rigid and breaking. As you know the rigid Oak can break while the flexible Willow does not so easily. Recently a straw bale cabin was put to the test on a shake table to get an idea of just how it would perform in an earthquake. It survived, as you can see in the video, an earthquake greater than anyone has experienced. If you plan to build a house and live in an earthquake prone area you might consider building it with bales.
Many of the straw bale homes that have been built have a post and beam frame while this cabin had the roof bearing on the straw bale walls without and posts and beams. However, if it had posts and beams the result would have been very similar in that the building would have withstood the test. Bales walls cut into a rigid post and beam frame work as shock absorbers for the frame in an earthquake. To those who have worked with bales in any way that probably does make sense.
