Yesterday’s blog post on Production Earthbag Building using Rice Hulls introduced one method for building walls with rice hulls. As you can see from the drawing above, the construction process is very straightforward. This method uses a standard post and beam frame with posts set in concrete footers and beams attached to the posts with post caps. The post and beam frame is carefully laid out, plumbed, leveled and squared to achieve good results. The roof is built after the concrete footers have set up. While you’re waiting for the concrete to dry, you can fill the gravel bags or tubes that help protect the rice hulls from moisture damage. Use double bags or tubes for added strength. You can fill the tubes with scoria or pumice in cold climates to create an insulated foundation.
With the roof and gravel bag foundation complete, now you’re ready to fill the rice hull tubes that wrap around the post and beam frame. Tie each tube to each post with baling twine. Fasten tubes out of sight on the backside of the posts to maintain the beauty of the wood frame. 6-penny common nails would work well for this purpose. Drape pre-cut lengths of baling twine every 2 feet or so for later attachment of plaster mesh. You can also use baling twine to tie the tubes together for added rigidity if necessary. Work carefully to keep everything in alignment so there are no bulges in the wall. If you do get some bulges, they can be dealt with by tying opposing dowels, bamboo or saplings together through the wall with twine. (See external pinning.) The tubes will create a solid, superinsulated wall after the plaster is complete.
Image source: Home Hardware
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