A-frame house made of strawbales?

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?

Thatched roofs have been around for a long time. I've never seen anyone use bales as the roofing material. The structure that would hold the weight of the bales and stucco would have to be fairly substantial. In my particular County bales have to be used in an infill manner to pass code currently. With the same footprint and height you get a lot more useable space with a conventional build.

You wouldn't likely build an A-frame with bricks but you can build an arch. Bales are like really big bricks. There are several vault designs for straw bales. The vaults also give more usable floor space than an A-frame.

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 agree with Andrew an arch would be considerably more sound structurally and open up some unusable floor space. Building in the round igloo style stronger yet. Depending on the exterior plaster, stucco, covering there may or may not be a transpiration issue. Straw bales with plasters kinda breathe and you want the bales to remain dry.
I like the look of an a-frame but find there is a lot of wasted space.

Thanks! I guess the most useful situation for an A-frame is in places with excessive snow.

The A-frame sheds snow, but not away from the structure. You need to reinforce the wall/roof to take the static load as the snow piles up. What you gain in simplicity and a really cool look, you lose in material costs and unusable floor space. The A-frame is only inexpensive in low-load settings.

So could straw bales be used to make a ceiling that is completely arched? - not a globe, just like half a cylinder. Maybe I am obsessed with using stawbales as a ceiling material

Yes. Do an internet search for straw bale and arch. There are several different approaches. Choose carefully. That is a lot of weight waiting to come down if you don't do it right.

Thanks! That search was useful. I am doing some research now on different parts of of the U.S. that I would like to live in, and the near-desert areas keep coming to the top - hence for the need for ultra-insulation in a roof (without going into high-tech, toxic options). My preferred option would be underground, but that seems to take a lot more $$ and has complications that I do not yet understand. Most likely the land will be predominantly flat, or rolling hills. An underground house with some walipinis (underground green houses) to keep the temps lower might be in order.

I wonder if it would be possible to stuff straw bales between the openings in engineered lumber I-joists... If it was possible, a straw bale A-frame could be constructed pretty easily. Just leave a gap of a couple inches between the bales and the [conventional] roofing and allow it to breath out the top... Hmmmmm. Thoughts?

If you engineer the wall/roof to carry the load, you could use cob, adobe, fired-brick or stone. Bales are really big (and slightly squishy) masonry. Use masonry designs for bales. If you want to use straw for an A-frame, put it in an appropriate form: thatch, panels, mats, strawjet columns, loose fill (light straw clay) etc.

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.

"If you want high R-values in a roof but want to use natural and/or sustainable material, there are lighter options."

...such as?

Besides straw in more appropriate forms, cotton, wool, rice husk, light clay straw, chopped cattail leaves, foamed MgO cement, vegetable oil based foams, recycled newspaper (pretty conventional). I am sure that others could come up with more options.

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 .