Bill and Athena Steen (www.caneloproject.com) are prominent figures in the straw bale world. With their focus on small, simple, inexpensive but beautiful buildings, they have been a major inspiration to us.
In February of 2009, they came to El Cajon, San Diego to teach a weekend workshop on load-bearing, bale-on-edge straw bale building.
A load-bearing straw bale building is one where the straw bale walls carry the weight of the roof. The Steens do a variation of the load bearing system that uses the door and window bucks to help support the roof as well as the straw bale walls. The advantage of a load-bearing system is that it uses a lot less wood (no posts) and utilizes that inherent compressive strength of the bales.
The bales in this building are laid on edge (with the narrow side face up). The advantage to bale-on-edge is that the bales take up less space (16″ thick wall instead of a 24″ thick wall). This is useful if you don’t have a lot of space to spare but is less stable and a little less adaptable than bales laid flat.
First, a test stack of bales needs to be compressed to find out what the final height of the wall will be, since all bales are slightly different. Then the door and window bucks can be cut to that height to meet the box beam. This way of building with bales is not yet permitted in San Diego (but since this building is less than 120 square feet it did not need a permit) so this was a fun, new experience for us.