Hi, Rikki,It sounds like you've got a system that is working well for you, and that is great. My view is that most building decisions have pluses and minuses. The pluses are the reason that we pick a system, and the minuses have to be dealt with. Usually, they can be, if we want to make the effort.
You ask what are the disadvantages of your three sided column approach. One is that a three sided box column will be substantially less strong than a four sided one. The fourth side makes a large difference in the weight the column can support, and the out of plane loads that it can resist. I'm not saying that you shouldn't build this way. Just that when a builder removes strength from one element in a building, she/he will have to be sure that sufficient strength remains, or add strength via other building elements.
If I'm visualizing correctly, I would say another disadvantage is that this kind of column interrupts the running bond stacking of the bales. This makes the wall less stable, and less able to resist out of plane loads. It means another interface between dissimilar materials, which can lead to air infiltration and plaster cracking. Again, these issues can be dealt with, if one chooses.
Best wishes, Derelict Derek Roff Language Learning Center Ortega Hall 129, MSC03-2100 University of New Mexico Albuquerque, NM 87131-0001 505/277-7368, fax 505/277-3885 Internet: derek@unm...--On Wednesday, October 13, 2010 1:20 PM +0200 Rikki Nitzkin <rikkinitzkin@earthlink...> wrote:
After listening to this last debate, I have a doubt... I have built very few wooden structures for straw (mostly I use loadbearing), but when I do, I have always found that using Box Beams (like the ones used for loadbearing roof-plates) vertically as a structure work very easily. In the case of using them as posts I only cover one side with OSB (9mm), not both, to save on material. They are easy to make, insulate, fix to the base plate, and permit you to top the structure off with a beam (probably another box beam) centered over the bales- which makes it easy to compress the bales within the structure (with car jacks or truck straps). This makes a very solid, straight wall with an insulated structure and permits using on-edge bales. When I do this (so far only with small "demonstration" buildings) it works well. I usually put the box beam posts in the corners, and around windows, and if there where a longer wall with no openings (never happened so far) I would put more posts in- with a maximum of 2,5 meters between posts (which is the length of the OSB). What are the disadvantages of doing this? I see only advantages... except (if using on-edge bales) that the first layer of plaster is a bit more difficult to apply. If there are no disadvantages, why don't people use this sistem very often? take care, Rikki