William Wallace wrote:Hello, and thanks for answering many of our questions about Earth Bag construction. I have my own two questions dealing with design and materials of an earthbag shelter.
Are there any more cost efficient and long term solutions to the large rolls of earth bags?
Is barbed wire still the most cost efficient stabilizing device to be installed in between earthbag layers?
Have you found there to be a simplest/easiest/cheapest design for someone on their first earthbag construction? I'm thinking of doing a small out-building first, to see if it's feasible and manageable on my own.
Thank you for your time here at Permies.com
It is odd that the large rolls of polypropylene tubing cost more than the equivalent footage when buying individually sewn bags, given that there is much more work entailed in producing the bags. I have found that the cheapest way to acquire earthbags is to purchase misprinted bags from manufacturers or printers; these may be available in large bales of a thousand bags. Sometimes you can find used or recycled bags from
feed stores and such, but you need to be careful that they are in good
enough shape and haven't been left out in the sun.
Barbed wire is by far the strongest way to introduce tensile strength to a wall, and
should be used especially in domes or situations where seismic resistance is needed. Another approach is with "Hyperadobe", or the use of long tubing of raschel mesh material (like what is commonly used to package bulky produce). When damp earthen fill is placed into this tubing and tamped into place, the fill oozes out of the pores and the wall becomes quite monolithic and the netting serves to provide the tensile strength. With this method it is possible to dispense with the need for plaster mesh as well, so it is a very economical and fast way to go.
It is wise to start with a small
project to get a feel for how to proceed. I would say that a simple vertical walled structure, either round or rectangular is simpler than trying to build a dome first.