Strawbale roundhouses like this can be built in as little as one day.
A kindred spirit sent me a memorable letter about 10 years ago. They had read about the strawbale roundhouse I helped build with the Lakota Sioux in South Dakota. (I recently found out the roundhouse later got destroyed in a flood.) For some reason the straw bales on that particular project were very difficult to bend into shape. Normally you can set one end of a bale on a raised object such as a small log, stomp the side of the bale in a few places and end up with a curved bale. Well, these bales would spring right back to their rectangular shape. So we’d stomp them again and again until they ‘cooperated’. But the bales would still gradually straighten out somewhat in the wall. We successfully finished the shell of the house on schedule, but I’ll never forget those bales.
I was pleasantly surprised to hear from the author of the letter that they build strawbale roundhouses in one day. I never got around to mailing them back for some reason and I’ve always wanted to connect with them somehow. Maybe they’ll see this blog post and write again.
Turnbuckles are used to tighten steel cable around the roundhouse.
With that background, here’s the basic process they use. It’s quick and easy to stack bales. They’re like pre-made giant building blocks that can be set in place by one person (or two people who are less strong). The tedious part as mentioned above is keeping the bales in alignment (= perfect circle). The author uses ¼” steel cable and turnbuckles on each course of bales. The cable is wrapped around the roundhouse and the ends fastened to each side of the pre-set door buck. The turnbuckle is added in a convenient location and then tightened until the bales are cinched into the desired radius. The turnbuckles are embedded in thick exterior plaster.
Image source: (Random image of strawbale roundhouse for illustrative purposes) Design Forward.net
Image source: Techni-cable
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does the building include stucco and everything in a day?
Oh no. That’s just the shell — the straw bales and reciprocal pole roof.
They sent me a photo. The roundhouse in the photo was quite small — about 12′ interior diameter.
Reflecting on this now, this building method seems like the fastest, easiest way to obtain durable, substantial shelter. Sure beats living in a tent. You could move in right away and finish it over time. It would be warm and comfortable enough in winter in northern climates, assuming you insulate the roof with R-45 or so and add a wood stove. Some people put bales on the roof and cover them with a tarp. I would use wood poles from a forest for the reciprocal roof.
So this explains my love affair with straw bale construction, and why building methods such as cob seem way down the list. You can build the shell of a small building in one day instead of spending months.
I suspect that using barbed wire and a simple barbed wire fence stretching tool would be much less expensive than 1/4″ steel cable, even if you needed to use multiple loops of barbed wire on each course.
If a barbed wire fence can be stretched tightly enough to withstand a butt scratching from a 2000lb cow, I suspect it would be sufficient to hold straw bales in place nicely.
If someone doesn’t want to hassle with the barbs on barbed wire, you could probably get away with typical electric fence wire. Again, it should be dramatically cheaper than wire cable.
Wire is added after each course of bales to make sure every course is the right size. Barbed wire on the outside of the bales would be a safety risk. Some might consider it an acceptable risk. Personally, I’d look for something safer. Not sure if electric fencing wire could withstand the tension. Seems like it would work. That sounds like the best option so far. Thanks for sharing.
You can buy barbless wire or high tension wire, either can be stretched and tied or crimped at a fraction of the cost of cable + turnbuckle. High-tensile wire is stronger than 1/4 inch cable and is $100 for 4000 feet (yes, four THOUSAND feet in a roll). It also make wonderful grape or vegetable trellis. Barbless wire is more expensive, but easier to work with, especially without special tools.
You can buy fence tensioners (strainers) that will pull each band tight for a few bucks each. http://www.tractorsupply.com/wire-strainer-3601180
Or buy the traditional stretching tool once for $40.
The cost difference is significant on even a small project unless you scrounge a very good deal on cable and turnbuckles.
Excellent suggestions, thanks.