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Do straight walls need buttressing even with a post-and-beam framework?

 
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This is probably a silly question, but I can't find an answer. Will straight earthbag walls be stabilised by the timber framework, or will they still need buttresses? If so, you can use internal earthbag walls as buttresses, right?
 
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I'm doing a 16ft long exterior load bearing wall 8 ft high, no end walls, no interior, no buttress.  I am NOT qualified to answer your question, as I am myself in experimental territory.  But I found this article about Bond Beam alternatives to give me the idea that if I re-enforce the wall from the base to the top with rebar, AND I tie it all together tight with a bond beam like this, it should be sufficient. As I understand it, a beam at the bottom connected to a beam at the top, tightened and making a sandwich, makes this super strong in terms of lateral or sheer force (pushing sideways to topple or fold it). In my case, it's not a stand-alone wall, it is supported by roof trusses, exactly as show in the pics in this article.

http://www.earthbagbuilding.com/articles/bondbeam.htm

I too would love to hear fro m others with more experience.  One thing I've not determined, aside from whether this scenario is legit, is what width of earthbag is needed?  14"?  16"?
 
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With my experience building earth block [mud brick in Australia] I can help.
We use barbed wire strung between the posts at every second layer.
We build 10 -12 inch wide walls.
Side internal walls can buttress earth walls.
 
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I'm not an earthbag builder, but if the bag walls are outside (or inside) the frame and continuous around the corners, they should work with the frame to stabilize the whole assembly. If they are unconnected infill sections between frame posts, they will depend quite a bit on the rigidity of the frame to stay put, and buttresses would be a big help.
 
Glenn Herbert
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The bond beam method in the article looks like it would work to make a strong section of wall, but it will do nothing to keep the whole wall from tipping over unless anchored to something else that is strong and rigid. The roof may support the wall top, but what supports the roof?
 
John C Daley
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I have found walls 9 feet high and at least 10 inches thick generally will stand by themselves.
With Earthbags being wider again I would expect it to be self supporting, by we always seem to err on the safe side.
Probally a good idea.
 
David Pug
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Glenn Herbert wrote:The bond beam method in the article looks like it would work to make a strong section of wall, but it will do nothing to keep the whole wall from tipping over unless anchored to something else that is strong and rigid. The roof may support the wall top, but what supports the roof?



Agreed. In my case, the end walls are lumber, so although I'm not using earthbag endwalls (which would be excellent for perpendicular support), I should still have sufficient structure to hold everything up, and the roof on.  It's a 16 ft span though, and I was told a buttress is best every 10 feet, but if I'm using barbed wire AND rebar, I'm confident it will be fine, maybe even overkill. (err on side of caution as @John said.)
 
John C Daley
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I would not buttress a 16 ft wall, unless it was 25 ft tall at least.
But most jobs I work on have posts / columns at 3 -4 Metre centres
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