I think that only way you could use straw with an A-frame would be as thatch, mats or panels.
You might approximate an A-frame look by corbelling, but because the bales are not strictly rigid, like fired brick or stone, I would be a little nervous about it.
Personally, I am not a big fan of the A-frame, though I was initially enamored by its (seeming) simplicity.
I like the look of an a-frame but find there is a lot of wasted space.
If you want high R-values in a roof but want to use natural and/or sustainable material, there are lighter options.
Straw bale vaults use the weight of the bale, instead of fighting it. Gothic arch vaults look similar to an A-frame.
Tom Connolly wrote:I have searched to answer this question but have not found one. Has anyone ever seen an A-frame house made of strawbales? I think it would be the ultimate in energy savings and also maybe lowered construction costs. I am guessing that there would have to be some kind of flashing covering the peak and top couple of feet of the roof...maybe also some kind of waterproof mat put over the straw and then a couple of inches of stucco...even then a convention roof over the stucco? Any ideas on this?
You want a catenary arch. I collected quite a bit of information on this and contributed it to https://en.wikibooks.org/wiki/Straw_Bale_Construction/Techniques/Pushing_the_Limit and https://en.wikibooks.org/wiki/Talk:Straw_Bale_Construction/Techniques/Pushing_the_Limit .
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